[lvgl] base implementation (#7116)

Co-authored-by: Jesse Hills <3060199+jesserockz@users.noreply.github.com>

CODEOWNERS

@@ -217,6 +217,7 @@ esphome/components/lock/* @esphome/core
 esphome/components/logger/* @esphome/core
 esphome/components/ltr390/* @latonita @sjtrny
 esphome/components/ltr_als_ps/* @latonita
+esphome/components/lvgl/* @clydebarrow
 esphome/components/m5stack_8angle/* @rnauber
 esphome/components/matrix_keypad/* @ssieb
 esphome/components/max31865/* @DAVe3283

esphome/components/lvgl/__init__.py

@@ -0,0 +1,212 @@
+import logging
+
+import esphome.codegen as cg
+from esphome.components.display import Display
+import esphome.config_validation as cv
+from esphome.const import (
+    CONF_AUTO_CLEAR_ENABLED,
+    CONF_BUFFER_SIZE,
+    CONF_ID,
+    CONF_LAMBDA,
+    CONF_PAGES,
+)
+from esphome.core import CORE, ID, Lambda
+from esphome.cpp_generator import MockObj
+from esphome.final_validate import full_config
+from esphome.helpers import write_file_if_changed
+
+from . import defines as df, helpers, lv_validation as lvalid
+from .label import label_spec
+from .lvcode import ConstantLiteral, LvContext
+
+# from .menu import menu_spec
+from .obj import obj_spec
+from .schemas import WIDGET_TYPES, any_widget_schema, obj_schema
+from .types import FontEngine, LvglComponent, lv_disp_t_ptr, lv_font_t, lvgl_ns
+from .widget import LvScrActType, Widget, add_widgets, set_obj_properties
+
+DOMAIN = "lvgl"
+DEPENDENCIES = ("display",)
+AUTO_LOAD = ("key_provider",)
+CODEOWNERS = ("@clydebarrow",)
+LOGGER = logging.getLogger(__name__)
+
+for widg in (
+    label_spec,
+    obj_spec,
+):
+    WIDGET_TYPES[widg.name] = widg
+
+lv_scr_act_spec = LvScrActType()
+lv_scr_act = Widget.create(
+    None, ConstantLiteral("lv_scr_act()"), lv_scr_act_spec, {}, parent=None
+)
+
+WIDGET_SCHEMA = any_widget_schema()
+
+
+async def add_init_lambda(lv_component, init):
+    if init:
+        lamb = await cg.process_lambda(Lambda(init), [(lv_disp_t_ptr, "lv_disp")])
+        cg.add(lv_component.add_init_lambda(lamb))
+
+
+lv_defines = {}  # Dict of #defines to provide as build flags
+
+
+def add_define(macro, value="1"):
+    if macro in lv_defines and lv_defines[macro] != value:
+        LOGGER.error(
+            "Redefinition of %s - was %s now %s", macro, lv_defines[macro], value
+        )
+    lv_defines[macro] = value
+
+
+def as_macro(macro, value):
+    if value is None:
+        return f"#define {macro}"
+    return f"#define {macro} {value}"
+
+
+LV_CONF_FILENAME = "lv_conf.h"
+LV_CONF_H_FORMAT = """\
+#pragma once
+{}
+"""
+
+
+def generate_lv_conf_h():
+    definitions = [as_macro(m, v) for m, v in lv_defines.items()]
+    definitions.sort()
+    return LV_CONF_H_FORMAT.format("\n".join(definitions))
+
+
+def final_validation(config):
+    global_config = full_config.get()
+    for display_id in config[df.CONF_DISPLAYS]:
+        path = global_config.get_path_for_id(display_id)[:-1]
+        display = global_config.get_config_for_path(path)
+        if CONF_LAMBDA in display:
+            raise cv.Invalid("Using lambda: in display config not compatible with LVGL")
+        if display[CONF_AUTO_CLEAR_ENABLED]:
+            raise cv.Invalid(
+                "Using auto_clear_enabled: true in display config not compatible with LVGL"
+            )
+    buffer_frac = config[CONF_BUFFER_SIZE]
+    if not CORE.is_host and buffer_frac > 0.5 and "psram" not in global_config:
+        LOGGER.warning("buffer_size: may need to be reduced without PSRAM")
+
+
+async def to_code(config):
+    cg.add_library("lvgl/lvgl", "8.4.0")
+    CORE.add_define("USE_LVGL")
+    # suppress default enabling of extra widgets
+    add_define("_LV_KCONFIG_PRESENT")
+    # Always enable - lots of things use it.
+    add_define("LV_DRAW_COMPLEX", "1")
+    add_define("LV_TICK_CUSTOM", "1")
+    add_define("LV_TICK_CUSTOM_INCLUDE", '"esphome/components/lvgl/lvgl_hal.h"')
+    add_define("LV_TICK_CUSTOM_SYS_TIME_EXPR", "(lv_millis())")
+    add_define("LV_MEM_CUSTOM", "1")
+    add_define("LV_MEM_CUSTOM_ALLOC", "lv_custom_mem_alloc")
+    add_define("LV_MEM_CUSTOM_FREE", "lv_custom_mem_free")
+    add_define("LV_MEM_CUSTOM_REALLOC", "lv_custom_mem_realloc")
+    add_define("LV_MEM_CUSTOM_INCLUDE", '"esphome/components/lvgl/lvgl_hal.h"')
+
+    add_define("LV_LOG_LEVEL", f"LV_LOG_LEVEL_{config[df.CONF_LOG_LEVEL]}")
+    add_define("LV_COLOR_DEPTH", config[df.CONF_COLOR_DEPTH])
+    for font in helpers.lv_fonts_used:
+        add_define(f"LV_FONT_{font.upper()}")
+
+    if config[df.CONF_COLOR_DEPTH] == 16:
+        add_define(
+            "LV_COLOR_16_SWAP",
+            "1" if config[df.CONF_BYTE_ORDER] == "big_endian" else "0",
+        )
+    add_define(
+        "LV_COLOR_CHROMA_KEY",
+        await lvalid.lv_color.process(config[df.CONF_TRANSPARENCY_KEY]),
+    )
+    CORE.add_build_flag("-Isrc")
+
+    cg.add_global(lvgl_ns.using)
+    lv_component = cg.new_Pvariable(config[CONF_ID])
+    await cg.register_component(lv_component, config)
+    Widget.create(config[CONF_ID], lv_component, WIDGET_TYPES[df.CONF_OBJ], config)
+    for display in config[df.CONF_DISPLAYS]:
+        cg.add(lv_component.add_display(await cg.get_variable(display)))
+
+    frac = config[CONF_BUFFER_SIZE]
+    if frac >= 0.75:
+        frac = 1
+    elif frac >= 0.375:
+        frac = 2
+    elif frac > 0.19:
+        frac = 4
+    else:
+        frac = 8
+    cg.add(lv_component.set_buffer_frac(int(frac)))
+    cg.add(lv_component.set_full_refresh(config[df.CONF_FULL_REFRESH]))
+
+    for font in helpers.esphome_fonts_used:
+        await cg.get_variable(font)
+        cg.new_Pvariable(ID(f"{font}_engine", True, type=FontEngine), MockObj(font))
+    default_font = config[df.CONF_DEFAULT_FONT]
+    if default_font not in helpers.lv_fonts_used:
+        add_define(
+            "LV_FONT_CUSTOM_DECLARE", f"LV_FONT_DECLARE(*{df.DEFAULT_ESPHOME_FONT})"
+        )
+        globfont_id = ID(
+            df.DEFAULT_ESPHOME_FONT,
+            True,
+            type=lv_font_t.operator("ptr").operator("const"),
+        )
+        cg.new_variable(globfont_id, MockObj(default_font))
+        add_define("LV_FONT_DEFAULT", df.DEFAULT_ESPHOME_FONT)
+    else:
+        add_define("LV_FONT_DEFAULT", default_font)
+
+    with LvContext():
+        await set_obj_properties(lv_scr_act, config)
+        await add_widgets(lv_scr_act, config)
+    Widget.set_completed()
+    await add_init_lambda(lv_component, LvContext.get_code())
+    for comp in helpers.lvgl_components_required:
+        CORE.add_define(f"USE_LVGL_{comp.upper()}")
+    for use in helpers.lv_uses:
+        add_define(f"LV_USE_{use.upper()}")
+    lv_conf_h_file = CORE.relative_src_path(LV_CONF_FILENAME)
+    write_file_if_changed(lv_conf_h_file, generate_lv_conf_h())
+    CORE.add_build_flag("-DLV_CONF_H=1")
+    CORE.add_build_flag(f'-DLV_CONF_PATH="{LV_CONF_FILENAME}"')
+
+
+def display_schema(config):
+    value = cv.ensure_list(cv.use_id(Display))(config)
+    return value or [cv.use_id(Display)(config)]
+
+
+FINAL_VALIDATE_SCHEMA = final_validation
+
+CONFIG_SCHEMA = (
+    cv.polling_component_schema("1s")
+    .extend(obj_schema("obj"))
+    .extend(
+        {
+            cv.GenerateID(CONF_ID): cv.declare_id(LvglComponent),
+            cv.GenerateID(df.CONF_DISPLAYS): display_schema,
+            cv.Optional(df.CONF_COLOR_DEPTH, default=16): cv.one_of(16),
+            cv.Optional(df.CONF_DEFAULT_FONT, default="montserrat_14"): lvalid.lv_font,
+            cv.Optional(df.CONF_FULL_REFRESH, default=False): cv.boolean,
+            cv.Optional(CONF_BUFFER_SIZE, default="100%"): cv.percentage,
+            cv.Optional(df.CONF_LOG_LEVEL, default="WARN"): cv.one_of(
+                *df.LOG_LEVELS, upper=True
+            ),
+            cv.Optional(df.CONF_BYTE_ORDER, default="big_endian"): cv.one_of(
+                "big_endian", "little_endian"
+            ),
+            cv.Optional(df.CONF_WIDGETS): cv.ensure_list(WIDGET_SCHEMA),
+            cv.Optional(df.CONF_TRANSPARENCY_KEY, default=0x000400): lvalid.lv_color,
+        }
+    )
+).add_extra(cv.has_at_least_one_key(CONF_PAGES, df.CONF_WIDGETS))

esphome/components/lvgl/defines.py

@@ -0,0 +1,487 @@
+"""
+This is the base of the import tree for LVGL. It contains constant definitions used elsewhere.
+Constants already defined in esphome.const are not duplicated here and must be imported where used.
+
+"""
+
+from esphome import codegen as cg, config_validation as cv
+from esphome.core import ID, Lambda
+from esphome.cpp_types import uint32
+from esphome.schema_extractors import SCHEMA_EXTRACT, schema_extractor
+
+from .lvcode import ConstantLiteral
+
+
+class LValidator:
+    """
+    A validator for a particular type used in LVGL. Usable in configs as a validator, also
+    has `process()` to convert a value during code generation
+    """
+
+    def __init__(self, validator, rtype, idtype=None, idexpr=None, retmapper=None):
+        self.validator = validator
+        self.rtype = rtype
+        self.idtype = idtype
+        self.idexpr = idexpr
+        self.retmapper = retmapper
+
+    def __call__(self, value):
+        if isinstance(value, cv.Lambda):
+            return cv.returning_lambda(value)
+        if self.idtype is not None and isinstance(value, ID):
+            return cv.use_id(self.idtype)(value)
+        return self.validator(value)
+
+    async def process(self, value, args=()):
+        if value is None:
+            return None
+        if isinstance(value, Lambda):
+            return cg.RawExpression(
+                f"{await cg.process_lambda(value, args, return_type=self.rtype)}()"
+            )
+        if self.idtype is not None and isinstance(value, ID):
+            return cg.RawExpression(f"{value}->{self.idexpr}")
+        if self.retmapper is not None:
+            return self.retmapper(value)
+        return cg.safe_exp(value)
+
+
+class LvConstant(LValidator):
+    """
+    Allow one of a list of choices, mapped to upper case, and prepend the choice with the prefix.
+    It's also permitted to include the prefix in the value
+    The property `one_of` has the single case validator, and `several_of` allows a list of constants.
+    """
+
+    def __init__(self, prefix: str, *choices):
+        self.prefix = prefix
+        self.choices = choices
+        prefixed_choices = [prefix + v for v in choices]
+        prefixed_validator = cv.one_of(*prefixed_choices, upper=True)
+
+        @schema_extractor("one_of")
+        def validator(value):
+            if value == SCHEMA_EXTRACT:
+                return self.choices
+            if isinstance(value, str) and value.startswith(self.prefix):
+                return prefixed_validator(value)
+            return self.prefix + cv.one_of(*choices, upper=True)(value)
+
+        super().__init__(validator, rtype=uint32)
+        self.one_of = LValidator(validator, uint32, retmapper=self.mapper)
+        self.several_of = LValidator(
+            cv.ensure_list(self.one_of), uint32, retmapper=self.mapper
+        )
+
+    def mapper(self, value, args=()):
+        if isinstance(value, list):
+            value = "|".join(value)
+        return ConstantLiteral(value)
+
+    def extend(self, *choices):
+        """
+        Extend an LVCconstant with additional choices.
+        :param choices: The extra choices
+        :return: A new LVConstant instance
+        """
+        return LvConstant(self.prefix, *(self.choices + choices))
+
+
+# Widgets
+CONF_LABEL = "label"
+
+# Parts
+CONF_MAIN = "main"
+CONF_SCROLLBAR = "scrollbar"
+CONF_INDICATOR = "indicator"
+CONF_KNOB = "knob"
+CONF_SELECTED = "selected"
+CONF_ITEMS = "items"
+CONF_TICKS = "ticks"
+CONF_TICK_STYLE = "tick_style"
+CONF_CURSOR = "cursor"
+CONF_TEXTAREA_PLACEHOLDER = "textarea_placeholder"
+
+LV_FONTS = list(f"montserrat_{s}" for s in range(8, 50, 2)) + [
+    "dejavu_16_persian_hebrew",
+    "simsun_16_cjk",
+    "unscii_8",
+    "unscii_16",
+]
+
+LV_EVENT = {
+    "PRESS": "PRESSED",
+    "SHORT_CLICK": "SHORT_CLICKED",
+    "LONG_PRESS": "LONG_PRESSED",
+    "LONG_PRESS_REPEAT": "LONG_PRESSED_REPEAT",
+    "CLICK": "CLICKED",
+    "RELEASE": "RELEASED",
+    "SCROLL_BEGIN": "SCROLL_BEGIN",
+    "SCROLL_END": "SCROLL_END",
+    "SCROLL": "SCROLL",
+    "FOCUS": "FOCUSED",
+    "DEFOCUS": "DEFOCUSED",
+    "READY": "READY",
+    "CANCEL": "CANCEL",
+}
+
+LV_EVENT_TRIGGERS = tuple(f"on_{x.lower()}" for x in LV_EVENT)
+
+
+LV_ANIM = LvConstant(
+    "LV_SCR_LOAD_ANIM_",
+    "NONE",
+    "OVER_LEFT",
+    "OVER_RIGHT",
+    "OVER_TOP",
+    "OVER_BOTTOM",
+    "MOVE_LEFT",
+    "MOVE_RIGHT",
+    "MOVE_TOP",
+    "MOVE_BOTTOM",
+    "FADE_IN",
+    "FADE_OUT",
+    "OUT_LEFT",
+    "OUT_RIGHT",
+    "OUT_TOP",
+    "OUT_BOTTOM",
+)
+
+LOG_LEVELS = (
+    "TRACE",
+    "INFO",
+    "WARN",
+    "ERROR",
+    "USER",
+    "NONE",
+)
+
+LV_LONG_MODES = LvConstant(
+    "LV_LABEL_LONG_",
+    "WRAP",
+    "DOT",
+    "SCROLL",
+    "SCROLL_CIRCULAR",
+    "CLIP",
+)
+
+STATES = (
+    "default",
+    "checked",
+    "focused",
+    "focus_key",
+    "edited",
+    "hovered",
+    "pressed",
+    "scrolled",
+    "disabled",
+    "user_1",
+    "user_2",
+    "user_3",
+    "user_4",
+)
+
+PARTS = (
+    CONF_MAIN,
+    CONF_SCROLLBAR,
+    CONF_INDICATOR,
+    CONF_KNOB,
+    CONF_SELECTED,
+    CONF_ITEMS,
+    CONF_TICKS,
+    CONF_CURSOR,
+    CONF_TEXTAREA_PLACEHOLDER,
+)
+
+KEYBOARD_MODES = LvConstant(
+    "LV_KEYBOARD_MODE_",
+    "TEXT_LOWER",
+    "TEXT_UPPER",
+    "SPECIAL",
+    "NUMBER",
+)
+ROLLER_MODES = LvConstant("LV_ROLLER_MODE_", "NORMAL", "INFINITE")
+DIRECTIONS = LvConstant("LV_DIR_", "LEFT", "RIGHT", "BOTTOM", "TOP")
+TILE_DIRECTIONS = DIRECTIONS.extend("HOR", "VER", "ALL")
+CHILD_ALIGNMENTS = LvConstant(
+    "LV_ALIGN_",
+    "TOP_LEFT",
+    "TOP_MID",
+    "TOP_RIGHT",
+    "LEFT_MID",
+    "CENTER",
+    "RIGHT_MID",
+    "BOTTOM_LEFT",
+    "BOTTOM_MID",
+    "BOTTOM_RIGHT",
+)
+
+SIBLING_ALIGNMENTS = LvConstant(
+    "LV_ALIGN_",
+    "OUT_LEFT_TOP",
+    "OUT_TOP_LEFT",
+    "OUT_TOP_MID",
+    "OUT_TOP_RIGHT",
+    "OUT_RIGHT_TOP",
+    "OUT_LEFT_MID",
+    "OUT_RIGHT_MID",
+    "OUT_LEFT_BOTTOM",
+    "OUT_BOTTOM_LEFT",
+    "OUT_BOTTOM_MID",
+    "OUT_BOTTOM_RIGHT",
+    "OUT_RIGHT_BOTTOM",
+)
+ALIGN_ALIGNMENTS = CHILD_ALIGNMENTS.extend(*SIBLING_ALIGNMENTS.choices)
+
+FLEX_FLOWS = LvConstant(
+    "LV_FLEX_FLOW_",
+    "ROW",
+    "COLUMN",
+    "ROW_WRAP",
+    "COLUMN_WRAP",
+    "ROW_REVERSE",
+    "COLUMN_REVERSE",
+    "ROW_WRAP_REVERSE",
+    "COLUMN_WRAP_REVERSE",
+)
+
+OBJ_FLAGS = (
+    "hidden",
+    "clickable",
+    "click_focusable",
+    "checkable",
+    "scrollable",
+    "scroll_elastic",
+    "scroll_momentum",
+    "scroll_one",
+    "scroll_chain_hor",
+    "scroll_chain_ver",
+    "scroll_chain",
+    "scroll_on_focus",
+    "scroll_with_arrow",
+    "snappable",
+    "press_lock",
+    "event_bubble",
+    "gesture_bubble",
+    "adv_hittest",
+    "ignore_layout",
+    "floating",
+    "overflow_visible",
+    "layout_1",
+    "layout_2",
+    "widget_1",
+    "widget_2",
+    "user_1",
+    "user_2",
+    "user_3",
+    "user_4",
+)
+
+ARC_MODES = LvConstant("LV_ARC_MODE_", "NORMAL", "REVERSE", "SYMMETRICAL")
+BAR_MODES = LvConstant("LV_BAR_MODE_", "NORMAL", "SYMMETRICAL", "RANGE")
+
+BTNMATRIX_CTRLS = (
+    "HIDDEN",
+    "NO_REPEAT",
+    "DISABLED",
+    "CHECKABLE",
+    "CHECKED",
+    "CLICK_TRIG",
+    "POPOVER",
+    "RECOLOR",
+    "CUSTOM_1",
+    "CUSTOM_2",
+)
+
+LV_BASE_ALIGNMENTS = (
+    "START",
+    "CENTER",
+    "END",
+)
+LV_CELL_ALIGNMENTS = LvConstant(
+    "LV_GRID_ALIGN_",
+    *LV_BASE_ALIGNMENTS,
+)
+LV_GRID_ALIGNMENTS = LV_CELL_ALIGNMENTS.extend(
+    "STRETCH",
+    "SPACE_EVENLY",
+    "SPACE_AROUND",
+    "SPACE_BETWEEN",
+)
+
+LV_FLEX_ALIGNMENTS = LvConstant(
+    "LV_FLEX_ALIGN_",
+    *LV_BASE_ALIGNMENTS,
+    "SPACE_EVENLY",
+    "SPACE_AROUND",
+    "SPACE_BETWEEN",
+)
+
+LV_MENU_MODES = LvConstant(
+    "LV_MENU_HEADER_",
+    "TOP_FIXED",
+    "TOP_UNFIXED",
+    "BOTTOM_FIXED",
+)
+
+LV_CHART_TYPES = (
+    "NONE",
+    "LINE",
+    "BAR",
+    "SCATTER",
+)
+LV_CHART_AXES = (
+    "PRIMARY_Y",
+    "SECONDARY_Y",
+    "PRIMARY_X",
+    "SECONDARY_X",
+)
+
+CONF_ACCEPTED_CHARS = "accepted_chars"
+CONF_ADJUSTABLE = "adjustable"
+CONF_ALIGN = "align"
+CONF_ALIGN_TO = "align_to"
+CONF_ANGLE_RANGE = "angle_range"
+CONF_ANIMATED = "animated"
+CONF_ANIMATION = "animation"
+CONF_ANTIALIAS = "antialias"
+CONF_ARC_LENGTH = "arc_length"
+CONF_AUTO_START = "auto_start"
+CONF_BACKGROUND_STYLE = "background_style"
+CONF_DECIMAL_PLACES = "decimal_places"
+CONF_COLUMN = "column"
+CONF_DIGITS = "digits"
+CONF_DISP_BG_COLOR = "disp_bg_color"
+CONF_DISP_BG_IMAGE = "disp_bg_image"
+CONF_BODY = "body"
+CONF_BUTTONS = "buttons"
+CONF_BYTE_ORDER = "byte_order"
+CONF_CHANGE_RATE = "change_rate"
+CONF_CLOSE_BUTTON = "close_button"
+CONF_COLOR_DEPTH = "color_depth"
+CONF_COLOR_END = "color_end"
+CONF_COLOR_START = "color_start"
+CONF_CONTROL = "control"
+CONF_DEFAULT = "default"
+CONF_DEFAULT_FONT = "default_font"
+CONF_DIR = "dir"
+CONF_DISPLAYS = "displays"
+CONF_END_ANGLE = "end_angle"
+CONF_END_VALUE = "end_value"
+CONF_ENTER_BUTTON = "enter_button"
+CONF_ENTRIES = "entries"
+CONF_FLAGS = "flags"
+CONF_FLEX_FLOW = "flex_flow"
+CONF_FLEX_ALIGN_MAIN = "flex_align_main"
+CONF_FLEX_ALIGN_CROSS = "flex_align_cross"
+CONF_FLEX_ALIGN_TRACK = "flex_align_track"
+CONF_FLEX_GROW = "flex_grow"
+CONF_FULL_REFRESH = "full_refresh"
+CONF_GRID_CELL_ROW_POS = "grid_cell_row_pos"
+CONF_GRID_CELL_COLUMN_POS = "grid_cell_column_pos"
+CONF_GRID_CELL_ROW_SPAN = "grid_cell_row_span"
+CONF_GRID_CELL_COLUMN_SPAN = "grid_cell_column_span"
+CONF_GRID_CELL_X_ALIGN = "grid_cell_x_align"
+CONF_GRID_CELL_Y_ALIGN = "grid_cell_y_align"
+CONF_GRID_COLUMN_ALIGN = "grid_column_align"
+CONF_GRID_COLUMNS = "grid_columns"
+CONF_GRID_ROW_ALIGN = "grid_row_align"
+CONF_GRID_ROWS = "grid_rows"
+CONF_HEADER_MODE = "header_mode"
+CONF_HOME = "home"
+CONF_INDICATORS = "indicators"
+CONF_KEY_CODE = "key_code"
+CONF_LABEL_GAP = "label_gap"
+CONF_LAYOUT = "layout"
+CONF_LEFT_BUTTON = "left_button"
+CONF_LINE_WIDTH = "line_width"
+CONF_LOG_LEVEL = "log_level"
+CONF_LONG_PRESS_TIME = "long_press_time"
+CONF_LONG_PRESS_REPEAT_TIME = "long_press_repeat_time"
+CONF_LVGL_ID = "lvgl_id"
+CONF_LONG_MODE = "long_mode"
+CONF_MAJOR = "major"
+CONF_MSGBOXES = "msgboxes"
+CONF_OBJ = "obj"
+CONF_OFFSET_X = "offset_x"
+CONF_OFFSET_Y = "offset_y"
+CONF_ONE_LINE = "one_line"
+CONF_ON_SELECT = "on_select"
+CONF_ONE_CHECKED = "one_checked"
+CONF_NEXT = "next"
+CONF_PAGE_WRAP = "page_wrap"
+CONF_PASSWORD_MODE = "password_mode"
+CONF_PIVOT_X = "pivot_x"
+CONF_PIVOT_Y = "pivot_y"
+CONF_PLACEHOLDER_TEXT = "placeholder_text"
+CONF_POINTS = "points"
+CONF_PREVIOUS = "previous"
+CONF_REPEAT_COUNT = "repeat_count"
+CONF_R_MOD = "r_mod"
+CONF_RECOLOR = "recolor"
+CONF_RIGHT_BUTTON = "right_button"
+CONF_ROLLOVER = "rollover"
+CONF_ROOT_BACK_BTN = "root_back_btn"
+CONF_ROWS = "rows"
+CONF_SCALES = "scales"
+CONF_SCALE_LINES = "scale_lines"
+CONF_SCROLLBAR_MODE = "scrollbar_mode"
+CONF_SELECTED_INDEX = "selected_index"
+CONF_SHOW_SNOW = "show_snow"
+CONF_SPIN_TIME = "spin_time"
+CONF_SRC = "src"
+CONF_START_ANGLE = "start_angle"
+CONF_START_VALUE = "start_value"
+CONF_STATES = "states"
+CONF_STRIDE = "stride"
+CONF_STYLE = "style"
+CONF_STYLE_ID = "style_id"
+CONF_SKIP = "skip"
+CONF_SYMBOL = "symbol"
+CONF_TAB_ID = "tab_id"
+CONF_TABS = "tabs"
+CONF_TEXT = "text"
+CONF_TILE = "tile"
+CONF_TILE_ID = "tile_id"
+CONF_TILES = "tiles"
+CONF_TITLE = "title"
+CONF_TOP_LAYER = "top_layer"
+CONF_TRANSPARENCY_KEY = "transparency_key"
+CONF_THEME = "theme"
+CONF_VISIBLE_ROW_COUNT = "visible_row_count"
+CONF_WIDGET = "widget"
+CONF_WIDGETS = "widgets"
+CONF_X = "x"
+CONF_Y = "y"
+CONF_ZOOM = "zoom"
+
+# Keypad keys
+
+LV_KEYS = LvConstant(
+    "LV_KEY_",
+    "UP",
+    "DOWN",
+    "RIGHT",
+    "LEFT",
+    "ESC",
+    "DEL",
+    "BACKSPACE",
+    "ENTER",
+    "NEXT",
+    "PREV",
+    "HOME",
+    "END",
+)
+
+
+# list of widgets and the parts allowed
+WIDGET_PARTS = {
+    CONF_LABEL: (CONF_MAIN, CONF_SCROLLBAR, CONF_SELECTED),
+    CONF_OBJ: (CONF_MAIN,),
+}
+
+DEFAULT_ESPHOME_FONT = "esphome_lv_default_font"
+
+
+def join_enums(enums, prefix=""):
+    return "|".join(f"(int){prefix}{e.upper()}" for e in enums)

esphome/components/lvgl/font.cpp

@@ -0,0 +1,76 @@
+#include "lvgl_esphome.h"
+
+#ifdef USE_LVGL_FONT
+namespace esphome {
+namespace lvgl {
+
+static const uint8_t *get_glyph_bitmap(const lv_font_t *font, uint32_t unicode_letter) {
+  auto *fe = (FontEngine *) font->dsc;
+  const auto *gd = fe->get_glyph_data(unicode_letter);
+  if (gd == nullptr)
+    return nullptr;
+  // esph_log_d(TAG, "Returning bitmap @  %X", (uint32_t)gd->data);
+
+  return gd->data;
+}
+
+static bool get_glyph_dsc_cb(const lv_font_t *font, lv_font_glyph_dsc_t *dsc, uint32_t unicode_letter, uint32_t next) {
+  auto *fe = (FontEngine *) font->dsc;
+  const auto *gd = fe->get_glyph_data(unicode_letter);
+  if (gd == nullptr)
+    return false;
+  dsc->adv_w = gd->offset_x + gd->width;
+  dsc->ofs_x = gd->offset_x;
+  dsc->ofs_y = fe->height - gd->height - gd->offset_y - fe->baseline;
+  dsc->box_w = gd->width;
+  dsc->box_h = gd->height;
+  dsc->is_placeholder = 0;
+  dsc->bpp = fe->bpp;
+  return true;
+}
+
+FontEngine::FontEngine(font::Font *esp_font) : font_(esp_font) {
+  this->bpp = esp_font->get_bpp();
+  this->lv_font_.dsc = this;
+  this->lv_font_.line_height = this->height = esp_font->get_height();
+  this->lv_font_.base_line = this->baseline = this->lv_font_.line_height - esp_font->get_baseline();
+  this->lv_font_.get_glyph_dsc = get_glyph_dsc_cb;
+  this->lv_font_.get_glyph_bitmap = get_glyph_bitmap;
+  this->lv_font_.subpx = LV_FONT_SUBPX_NONE;
+  this->lv_font_.underline_position = -1;
+  this->lv_font_.underline_thickness = 1;
+}
+
+const lv_font_t *FontEngine::get_lv_font() { return &this->lv_font_; }
+
+const font::GlyphData *FontEngine::get_glyph_data(uint32_t unicode_letter) {
+  if (unicode_letter == last_letter_)
+    return this->last_data_;
+  uint8_t unicode[5];
+  memset(unicode, 0, sizeof unicode);
+  if (unicode_letter > 0xFFFF) {
+    unicode[0] = 0xF0 + ((unicode_letter >> 18) & 0x7);
+    unicode[1] = 0x80 + ((unicode_letter >> 12) & 0x3F);
+    unicode[2] = 0x80 + ((unicode_letter >> 6) & 0x3F);
+    unicode[3] = 0x80 + (unicode_letter & 0x3F);
+  } else if (unicode_letter > 0x7FF) {
+    unicode[0] = 0xE0 + ((unicode_letter >> 12) & 0xF);
+    unicode[1] = 0x80 + ((unicode_letter >> 6) & 0x3F);
+    unicode[2] = 0x80 + (unicode_letter & 0x3F);
+  } else if (unicode_letter > 0x7F) {
+    unicode[0] = 0xC0 + ((unicode_letter >> 6) & 0x1F);
+    unicode[1] = 0x80 + (unicode_letter & 0x3F);
+  } else {
+    unicode[0] = unicode_letter;
+  }
+  int match_length;
+  int glyph_n = this->font_->match_next_glyph(unicode, &match_length);
+  if (glyph_n < 0)
+    return nullptr;
+  this->last_data_ = this->font_->get_glyphs()[glyph_n].get_glyph_data();
+  this->last_letter_ = unicode_letter;
+  return this->last_data_;
+}
+}  // namespace lvgl
+}  // namespace esphome
+#endif  // USES_LVGL_FONT

esphome/components/lvgl/helpers.py

@@ -0,0 +1,70 @@
+import re
+
+from esphome import config_validation as cv
+from esphome.config import Config
+from esphome.const import CONF_ARGS, CONF_FORMAT
+from esphome.core import CORE, ID
+from esphome.yaml_util import ESPHomeDataBase
+
+lv_uses = {
+    "USER_DATA",
+    "LOG",
+    "STYLE",
+    "FONT_PLACEHOLDER",
+    "THEME_DEFAULT",
+}
+
+
+def add_lv_use(*names):
+    for name in names:
+        lv_uses.add(name)
+
+
+lv_fonts_used = set()
+esphome_fonts_used = set()
+REQUIRED_COMPONENTS = {}
+lvgl_components_required = set()
+
+
+def validate_printf(value):
+    cfmt = r"""
+    (                                  # start of capture group 1
+    %                                  # literal "%"
+    (?:[-+0 #]{0,5})                   # optional flags
+    (?:\d+|\*)?                        # width
+    (?:\.(?:\d+|\*))?                  # precision
+    (?:h|l|ll|w|I|I32|I64)?            # size
+    [cCdiouxXeEfgGaAnpsSZ]             # type
+    )
+    """  # noqa
+    matches = re.findall(cfmt, value[CONF_FORMAT], flags=re.X)
+    if len(matches) != len(value[CONF_ARGS]):
+        raise cv.Invalid(
+            f"Found {len(matches)} printf-patterns ({', '.join(matches)}), but {len(value[CONF_ARGS])} args were given!"
+        )
+    return value
+
+
+def get_line_marks(value) -> list:
+    """
+    If possible, return a preprocessor directive to identify the line number where the given id was defined.
+    :param id: The id in question
+    :return: A list containing zero or more line directives
+    """
+    path = None
+    if isinstance(value, ESPHomeDataBase):
+        path = value.esp_range
+    elif isinstance(value, ID) and isinstance(CORE.config, Config):
+        path = CORE.config.get_path_for_id(value)[:-1]
+        path = CORE.config.get_deepest_document_range_for_path(path)
+    if path is None:
+        return []
+    return [path.start_mark.as_line_directive]
+
+
+def requires_component(comp):
+    def validator(value):
+        lvgl_components_required.add(comp)
+        return cv.requires_component(comp)(value)
+
+    return validator

esphome/components/lvgl/label.py

@@ -0,0 +1,34 @@
+import esphome.config_validation as cv
+
+from .defines import CONF_LABEL, CONF_LONG_MODE, CONF_RECOLOR, CONF_TEXT, LV_LONG_MODES
+from .lv_validation import lv_bool, lv_text
+from .schemas import TEXT_SCHEMA
+from .types import lv_label_t
+from .widget import Widget, WidgetType
+
+
+class LabelType(WidgetType):
+    def __init__(self):
+        super().__init__(
+            CONF_LABEL,
+            TEXT_SCHEMA.extend(
+                {
+                    cv.Optional(CONF_RECOLOR): lv_bool,
+                    cv.Optional(CONF_LONG_MODE): LV_LONG_MODES.one_of,
+                }
+            ),
+        )
+
+    @property
+    def w_type(self):
+        return lv_label_t
+
+    async def to_code(self, w: Widget, config):
+        """For a text object, create and set text"""
+        if value := config.get(CONF_TEXT):
+            w.set_property(CONF_TEXT, await lv_text.process(value))
+        w.set_property(CONF_LONG_MODE, config)
+        w.set_property(CONF_RECOLOR, config)
+
+
+label_spec = LabelType()

esphome/components/lvgl/lv_validation.py

@@ -0,0 +1,170 @@
+import esphome.codegen as cg
+from esphome.components.binary_sensor import BinarySensor
+from esphome.components.color import ColorStruct
+from esphome.components.font import Font
+from esphome.components.sensor import Sensor
+from esphome.components.text_sensor import TextSensor
+import esphome.config_validation as cv
+from esphome.const import CONF_ARGS, CONF_COLOR, CONF_FORMAT
+from esphome.core import HexInt
+from esphome.cpp_generator import MockObj
+from esphome.helpers import cpp_string_escape
+from esphome.schema_extractors import SCHEMA_EXTRACT, schema_extractor
+
+from . import types as ty
+from .defines import LV_FONTS, LValidator, LvConstant
+from .helpers import (
+    esphome_fonts_used,
+    lv_fonts_used,
+    lvgl_components_required,
+    requires_component,
+)
+from .lvcode import ConstantLiteral, lv_expr
+from .types import lv_font_t
+
+
+@schema_extractor("one_of")
+def color(value):
+    if value == SCHEMA_EXTRACT:
+        return ["hex color value", "color ID"]
+    if isinstance(value, int):
+        return value
+    return cv.use_id(ColorStruct)(value)
+
+
+def color_retmapper(value):
+    if isinstance(value, cv.Lambda):
+        return cv.returning_lambda(value)
+    if isinstance(value, int):
+        hexval = HexInt(value)
+        return lv_expr.color_hex(hexval)
+    # Must be an id
+    lvgl_components_required.add(CONF_COLOR)
+    return lv_expr.color_from(MockObj(value))
+
+
+def pixels_or_percent(value):
+    """A length in one axis - either a number (pixels) or a percentage"""
+    if value == SCHEMA_EXTRACT:
+        return ["pixels", "..%"]
+    if isinstance(value, int):
+        return str(cv.int_(value))
+    # Will throw an exception if not a percentage.
+    return f"lv_pct({int(cv.percentage(value) * 100)})"
+
+
+def zoom(value):
+    value = cv.float_range(0.1, 10.0)(value)
+    return int(value * 256)
+
+
+def angle(value):
+    """
+    Validation for an angle in degrees, converted to an integer representing 0.1deg units
+    :param value: The input in the range 0..360
+    :return: An angle in 1/10 degree units.
+    """
+    return int(cv.float_range(0.0, 360.0)(cv.angle(value)) * 10)
+
+
+@schema_extractor("one_of")
+def size(value):
+    """A size in one axis - one of "size_content", a number (pixels) or a percentage"""
+    if value == SCHEMA_EXTRACT:
+        return ["size_content", "pixels", "..%"]
+    if isinstance(value, str) and value.lower().endswith("px"):
+        value = cv.int_(value[:-2])
+    if isinstance(value, str) and not value.endswith("%"):
+        if value.upper() == "SIZE_CONTENT":
+            return "LV_SIZE_CONTENT"
+        raise cv.Invalid("must be 'size_content', a pixel position or a percentage")
+    if isinstance(value, int):
+        return str(cv.int_(value))
+    # Will throw an exception if not a percentage.
+    return f"lv_pct({int(cv.percentage(value) * 100)})"
+
+
+@schema_extractor("one_of")
+def opacity(value):
+    consts = LvConstant("LV_OPA_", "TRANSP", "COVER")
+    if value == SCHEMA_EXTRACT:
+        return consts.choices
+    value = cv.Any(cv.percentage, consts.one_of)(value)
+    if isinstance(value, float):
+        return int(value * 255)
+    return value
+
+
+def stop_value(value):
+    return cv.int_range(0, 255)(value)
+
+
+lv_color = LValidator(color, ty.lv_color_t, retmapper=color_retmapper)
+lv_bool = LValidator(cv.boolean, cg.bool_, BinarySensor, "get_state()")
+
+
+def lvms_validator_(value):
+    if value == "never":
+        value = "2147483647ms"
+    return cv.positive_time_period_milliseconds(value)
+
+
+lv_milliseconds = LValidator(
+    lvms_validator_,
+    cg.int32,
+    retmapper=lambda x: x.total_milliseconds,
+)
+
+
+class TextValidator(LValidator):
+    def __init__(self):
+        super().__init__(
+            cv.string,
+            cg.const_char_ptr,
+            TextSensor,
+            "get_state().c_str()",
+            lambda s: cg.safe_exp(f"{s}"),
+        )
+
+    def __call__(self, value):
+        if isinstance(value, dict):
+            return value
+        return super().__call__(value)
+
+    async def process(self, value, args=()):
+        if isinstance(value, dict):
+            args = [str(x) for x in value[CONF_ARGS]]
+            arg_expr = cg.RawExpression(",".join(args))
+            format_str = cpp_string_escape(value[CONF_FORMAT])
+            return f"str_sprintf({format_str}, {arg_expr}).c_str()"
+        return await super().process(value, args)
+
+
+lv_text = TextValidator()
+lv_float = LValidator(cv.float_, cg.float_, Sensor, "get_state()")
+lv_int = LValidator(cv.int_, cg.int_, Sensor, "get_state()")
+
+
+class LvFont(LValidator):
+    def __init__(self):
+        def lv_builtin_font(value):
+            fontval = cv.one_of(*LV_FONTS, lower=True)(value)
+            lv_fonts_used.add(fontval)
+            return "&lv_font_" + fontval
+
+        def validator(value):
+            if value == SCHEMA_EXTRACT:
+                return LV_FONTS
+            if isinstance(value, str) and value.lower() in LV_FONTS:
+                return lv_builtin_font(value)
+            fontval = cv.use_id(Font)(value)
+            esphome_fonts_used.add(fontval)
+            return requires_component("font")(f"{fontval}_engine->get_lv_font()")
+
+        super().__init__(validator, lv_font_t)
+
+    async def process(self, value, args=()):
+        return ConstantLiteral(value)
+
+
+lv_font = LvFont()

esphome/components/lvgl/lvcode.py

@@ -0,0 +1,237 @@
+import abc
+import logging
+from typing import Union
+
+from esphome import codegen as cg
+from esphome.core import ID, Lambda
+from esphome.cpp_generator import (
+    AssignmentExpression,
+    CallExpression,
+    Expression,
+    LambdaExpression,
+    Literal,
+    MockObj,
+    RawExpression,
+    RawStatement,
+    SafeExpType,
+    Statement,
+    VariableDeclarationExpression,
+    statement,
+)
+
+from .helpers import get_line_marks
+
+_LOGGER = logging.getLogger(__name__)
+
+
+class CodeContext(abc.ABC):
+    """
+    A class providing a context for code generation. Generated code will be added to the
+    current context. A new context will stack on the current context, and restore it
+    when done. Used with the `with` statement.
+    """
+
+    code_context = None
+
+    @abc.abstractmethod
+    def add(self, expression: Union[Expression, Statement]):
+        pass
+
+    @staticmethod
+    def append(expression: Union[Expression, Statement]):
+        if CodeContext.code_context is not None:
+            CodeContext.code_context.add(expression)
+        return expression
+
+    def __init__(self):
+        self.previous: Union[CodeContext | None] = None
+
+    def __enter__(self):
+        self.previous = CodeContext.code_context
+        CodeContext.code_context = self
+
+    def __exit__(self, *args):
+        CodeContext.code_context = self.previous
+
+
+class MainContext(CodeContext):
+    """
+    Code generation into the main() function
+    """
+
+    def add(self, expression: Union[Expression, Statement]):
+        return cg.add(expression)
+
+
+class LvContext(CodeContext):
+    """
+    Code generation into the LVGL initialisation code (called in `setup()`)
+    """
+
+    lv_init_code: list["Statement"] = []
+
+    @staticmethod
+    def lv_add(expression: Union[Expression, Statement]):
+        if isinstance(expression, Expression):
+            expression = statement(expression)
+        if not isinstance(expression, Statement):
+            raise ValueError(
+                f"Add '{expression}' must be expression or statement, not {type(expression)}"
+            )
+        LvContext.lv_init_code.append(expression)
+        _LOGGER.debug("LV Adding: %s", expression)
+        return expression
+
+    @staticmethod
+    def get_code():
+        code = []
+        for exp in LvContext.lv_init_code:
+            text = str(statement(exp))
+            text = text.rstrip()
+            code.append(text)
+        return "\n".join(code) + "\n\n"
+
+    def add(self, expression: Union[Expression, Statement]):
+        return LvContext.lv_add(expression)
+
+    def set_style(self, prop):
+        return MockObj("lv_set_style_{prop}", "")
+
+
+class LambdaContext(CodeContext):
+    """
+    A context that will accumlate code for use in a lambda.
+    """
+
+    def __init__(
+        self,
+        parameters: list[tuple[SafeExpType, str]],
+        return_type: SafeExpType = None,
+    ):
+        super().__init__()
+        self.code_list: list[Statement] = []
+        self.parameters = parameters
+        self.return_type = return_type
+
+    def add(self, expression: Union[Expression, Statement]):
+        self.code_list.append(expression)
+        return expression
+
+    async def code(self) -> LambdaExpression:
+        code_text = []
+        for exp in self.code_list:
+            text = str(statement(exp))
+            text = text.rstrip()
+            code_text.append(text)
+        return await cg.process_lambda(
+            Lambda("\n".join(code_text) + "\n\n"),
+            self.parameters,
+            return_type=self.return_type,
+        )
+
+
+class LocalVariable(MockObj):
+    """
+    Create a local variable and enclose the code using it within a block.
+    """
+
+    def __init__(self, name, type, modifier=None, rhs=None):
+        base = ID(name, True, type)
+        super().__init__(base, "")
+        self.modifier = modifier
+        self.rhs = rhs
+
+    def __enter__(self):
+        CodeContext.append(RawStatement("{"))
+        CodeContext.append(
+            VariableDeclarationExpression(self.base.type, self.modifier, self.base.id)
+        )
+        if self.rhs is not None:
+            CodeContext.append(AssignmentExpression(None, "", self.base, self.rhs))
+        return self.base
+
+    def __exit__(self, *args):
+        CodeContext.append(RawStatement("}"))
+
+
+class MockLv:
+    """
+    A mock object that can be used to generate LVGL calls.
+    """
+
+    def __init__(self, base):
+        self.base = base
+
+    def __getattr__(self, attr: str) -> "MockLv":
+        return MockLv(f"{self.base}{attr}")
+
+    def append(self, expression):
+        CodeContext.append(expression)
+
+    def __call__(self, *args: SafeExpType) -> "MockObj":
+        call = CallExpression(self.base, *args)
+        result = MockObj(call, "")
+        self.append(result)
+        return result
+
+    def __str__(self):
+        return str(self.base)
+
+    def __repr__(self):
+        return f"MockLv<{str(self.base)}>"
+
+    def call(self, prop, *args):
+        call = CallExpression(RawExpression(f"{self.base}{prop}"), *args)
+        result = MockObj(call, "")
+        self.append(result)
+        return result
+
+    def cond_if(self, expression: Expression):
+        CodeContext.append(RawExpression(f"if({expression}) {{"))
+
+    def cond_else(self):
+        CodeContext.append(RawExpression("} else {"))
+
+    def cond_endif(self):
+        CodeContext.append(RawExpression("}"))
+
+
+class LvExpr(MockLv):
+    def __getattr__(self, attr: str) -> "MockLv":
+        return LvExpr(f"{self.base}{attr}")
+
+    def append(self, expression):
+        pass
+
+
+# Top level mock for generic lv_ calls to be recorded
+lv = MockLv("lv_")
+# Just generate an expression
+lv_expr = LvExpr("lv_")
+# Mock for lv_obj_ calls
+lv_obj = MockLv("lv_obj_")
+
+
+# equivalent to cg.add() for the lvgl init context
+def lv_add(expression: Union[Expression, Statement]):
+    return CodeContext.append(expression)
+
+
+def add_line_marks(where):
+    for mark in get_line_marks(where):
+        lv_add(cg.RawStatement(mark))
+
+
+def lv_assign(target, expression):
+    lv_add(RawExpression(f"{target} = {expression}"))
+
+
+class ConstantLiteral(Literal):
+    __slots__ = ("constant",)
+
+    def __init__(self, constant: str):
+        super().__init__()
+        self.constant = constant
+
+    def __str__(self):
+        return self.constant

esphome/components/lvgl/lvgl_esphome.cpp

@@ -0,0 +1,129 @@
+#include "esphome/core/defines.h"
+#include "esphome/core/log.h"
+#include "esphome/core/helpers.h"
+#include "esphome/core/hal.h"
+#include "lvgl_hal.h"
+#include "lvgl_esphome.h"
+
+namespace esphome {
+namespace lvgl {
+static const char *const TAG = "lvgl";
+
+lv_event_code_t lv_custom_event;  // NOLINT
+void LvglComponent::dump_config() { ESP_LOGCONFIG(TAG, "LVGL:"); }
+void LvglComponent::draw_buffer_(const lv_area_t *area, const uint8_t *ptr) {
+  for (auto *display : this->displays_) {
+    display->draw_pixels_at(area->x1, area->y1, lv_area_get_width(area), lv_area_get_height(area), ptr,
+                            display::COLOR_ORDER_RGB, LV_BITNESS, LV_COLOR_16_SWAP);
+  }
+}
+
+void LvglComponent::flush_cb_(lv_disp_drv_t *disp_drv, const lv_area_t *area, lv_color_t *color_p) {
+  auto now = millis();
+  this->draw_buffer_(area, (const uint8_t *) color_p);
+  ESP_LOGV(TAG, "flush_cb, area=%d/%d, %d/%d took %dms", area->x1, area->y1, lv_area_get_width(area),
+           lv_area_get_height(area), (int) (millis() - now));
+  lv_disp_flush_ready(disp_drv);
+}
+
+void LvglComponent::setup() {
+  ESP_LOGCONFIG(TAG, "LVGL Setup starts");
+#if LV_USE_LOG
+  lv_log_register_print_cb(log_cb);
+#endif
+  lv_init();
+  lv_custom_event = static_cast<lv_event_code_t>(lv_event_register_id());
+  auto *display = this->displays_[0];
+  size_t buffer_pixels = display->get_width() * display->get_height() / this->buffer_frac_;
+  auto buf_bytes = buffer_pixels * LV_COLOR_DEPTH / 8;
+  auto *buf = lv_custom_mem_alloc(buf_bytes);
+  if (buf == nullptr) {
+    ESP_LOGE(TAG, "Malloc failed to allocate %zu bytes", buf_bytes);
+    this->mark_failed();
+    this->status_set_error("Memory allocation failure");
+    return;
+  }
+  lv_disp_draw_buf_init(&this->draw_buf_, buf, nullptr, buffer_pixels);
+  lv_disp_drv_init(&this->disp_drv_);
+  this->disp_drv_.draw_buf = &this->draw_buf_;
+  this->disp_drv_.user_data = this;
+  this->disp_drv_.full_refresh = this->full_refresh_;
+  this->disp_drv_.flush_cb = static_flush_cb;
+  this->disp_drv_.rounder_cb = rounder_cb;
+  switch (display->get_rotation()) {
+    case display::DISPLAY_ROTATION_0_DEGREES:
+      break;
+    case display::DISPLAY_ROTATION_90_DEGREES:
+      this->disp_drv_.sw_rotate = true;
+      this->disp_drv_.rotated = LV_DISP_ROT_90;
+      break;
+    case display::DISPLAY_ROTATION_180_DEGREES:
+      this->disp_drv_.sw_rotate = true;
+      this->disp_drv_.rotated = LV_DISP_ROT_180;
+      break;
+    case display::DISPLAY_ROTATION_270_DEGREES:
+      this->disp_drv_.sw_rotate = true;
+      this->disp_drv_.rotated = LV_DISP_ROT_270;
+      break;
+  }
+  display->set_rotation(display::DISPLAY_ROTATION_0_DEGREES);
+  this->disp_drv_.hor_res = (lv_coord_t) display->get_width();
+  this->disp_drv_.ver_res = (lv_coord_t) display->get_height();
+  ESP_LOGV(TAG, "sw_rotate = %d, rotated=%d", this->disp_drv_.sw_rotate, this->disp_drv_.rotated);
+  this->disp_ = lv_disp_drv_register(&this->disp_drv_);
+  for (const auto &v : this->init_lambdas_)
+    v(this->disp_);
+  lv_disp_trig_activity(this->disp_);
+  ESP_LOGCONFIG(TAG, "LVGL Setup complete");
+}
+}  // namespace lvgl
+}  // namespace esphome
+
+size_t lv_millis(void) { return esphome::millis(); }
+
+#if defined(USE_HOST) || defined(USE_RP2040) || defined(USE_ESP8266)
+void *lv_custom_mem_alloc(size_t size) {
+  auto *ptr = malloc(size);  // NOLINT
+  if (ptr == nullptr) {
+    esphome::ESP_LOGE(esphome::lvgl::TAG, "Failed to allocate %zu bytes", size);
+  }
+  return ptr;
+}
+void lv_custom_mem_free(void *ptr) { return free(ptr); }                            // NOLINT
+void *lv_custom_mem_realloc(void *ptr, size_t size) { return realloc(ptr, size); }  // NOLINT
+#else
+static unsigned cap_bits = MALLOC_CAP_SPIRAM | MALLOC_CAP_8BIT;  // NOLINT
+
+void *lv_custom_mem_alloc(size_t size) {
+  void *ptr;
+  ptr = heap_caps_malloc(size, cap_bits);
+  if (ptr == nullptr) {
+    cap_bits = MALLOC_CAP_8BIT;
+    ptr = heap_caps_malloc(size, cap_bits);
+  }
+  if (ptr == nullptr) {
+    esphome::ESP_LOGE(esphome::lvgl::TAG, "Failed to allocate %zu bytes", size);
+    return nullptr;
+  }
+#ifdef ESPHOME_LOG_HAS_VERBOSE
+  esphome::ESP_LOGV(esphome::lvgl::TAG, "allocate %zu - > %p", size, ptr);
+#endif
+  return ptr;
+}
+
+void lv_custom_mem_free(void *ptr) {
+#ifdef ESPHOME_LOG_HAS_VERBOSE
+  esphome::ESP_LOGV(esphome::lvgl::TAG, "free %p", ptr);
+#endif
+  if (ptr == nullptr)
+    return;
+  heap_caps_free(ptr);
+}
+
+void *lv_custom_mem_realloc(void *ptr, size_t size) {
+#ifdef ESPHOME_LOG_HAS_VERBOSE
+  esphome::ESP_LOGV(esphome::lvgl::TAG, "realloc %p: %zu", ptr, size);
+#endif
+  return heap_caps_realloc(ptr, size, cap_bits);
+}
+#endif

esphome/components/lvgl/lvgl_esphome.h

@@ -0,0 +1,119 @@
+#pragma once
+#include "esphome/core/defines.h"
+#ifdef USE_LVGL
+
+// required for clang-tidy
+#ifndef LV_CONF_H
+#define LV_CONF_SKIP 1  // NOLINT
+#endif
+
+#include "esphome/components/display/display.h"
+#include "esphome/components/display/display_color_utils.h"
+#include "esphome/core/component.h"
+#include "esphome/core/hal.h"
+#include "esphome/core/log.h"
+#include <lvgl.h>
+#include <vector>
+
+#ifdef USE_LVGL_FONT
+#include "esphome/components/font/font.h"
+#endif
+namespace esphome {
+namespace lvgl {
+
+extern lv_event_code_t lv_custom_event;  // NOLINT
+#ifdef USE_LVGL_COLOR
+static lv_color_t lv_color_from(Color color) { return lv_color_make(color.red, color.green, color.blue); }
+#endif
+#if LV_COLOR_DEPTH == 16
+static const display::ColorBitness LV_BITNESS = display::ColorBitness::COLOR_BITNESS_565;
+#elif LV_COLOR_DEPTH == 32
+static const display::ColorBitness LV_BITNESS = display::ColorBitness::COLOR_BITNESS_888;
+#else
+static const display::ColorBitness LV_BITNESS = display::ColorBitness::COLOR_BITNESS_332;
+#endif
+
+// Parent class for things that wrap an LVGL object
+class LvCompound {
+ public:
+  virtual void set_obj(lv_obj_t *lv_obj) { this->obj = lv_obj; }
+  lv_obj_t *obj{};
+};
+
+using LvLambdaType = std::function<void(lv_obj_t *)>;
+using set_value_lambda_t = std::function<void(float)>;
+using event_callback_t = void(_lv_event_t *);
+using text_lambda_t = std::function<const char *()>;
+
+#ifdef USE_LVGL_FONT
+class FontEngine {
+ public:
+  FontEngine(font::Font *esp_font);
+  const lv_font_t *get_lv_font();
+
+  const font::GlyphData *get_glyph_data(uint32_t unicode_letter);
+  uint16_t baseline{};
+  uint16_t height{};
+  uint8_t bpp{};
+
+ protected:
+  font::Font *font_{};
+  uint32_t last_letter_{};
+  const font::GlyphData *last_data_{};
+  lv_font_t lv_font_{};
+};
+#endif  // USE_LVGL_FONT
+
+class LvglComponent : public PollingComponent {
+  constexpr static const char *const TAG = "lvgl";
+
+ public:
+  static void static_flush_cb(lv_disp_drv_t *disp_drv, const lv_area_t *area, lv_color_t *color_p) {
+    reinterpret_cast<LvglComponent *>(disp_drv->user_data)->flush_cb_(disp_drv, area, color_p);
+  }
+
+  float get_setup_priority() const override { return setup_priority::PROCESSOR; }
+  static void log_cb(const char *buf) {
+    esp_log_printf_(ESPHOME_LOG_LEVEL_INFO, TAG, 0, "%.*s", (int) strlen(buf) - 1, buf);
+  }
+  static void rounder_cb(lv_disp_drv_t *disp_drv, lv_area_t *area) {
+    // make sure all coordinates are even
+    if (area->x1 & 1)
+      area->x1--;
+    if (!(area->x2 & 1))
+      area->x2++;
+    if (area->y1 & 1)
+      area->y1--;
+    if (!(area->y2 & 1))
+      area->y2++;
+  }
+
+  void loop() override { lv_timer_handler_run_in_period(5); }
+  void setup() override;
+
+  void update() override {}
+
+  void add_display(display::Display *display) { this->displays_.push_back(display); }
+  void add_init_lambda(const std::function<void(lv_disp_t *)> &lamb) { this->init_lambdas_.push_back(lamb); }
+  void dump_config() override;
+  void set_full_refresh(bool full_refresh) { this->full_refresh_ = full_refresh; }
+  void set_buffer_frac(size_t frac) { this->buffer_frac_ = frac; }
+  lv_disp_t *get_disp() { return this->disp_; }
+
+ protected:
+  void draw_buffer_(const lv_area_t *area, const uint8_t *ptr);
+  void flush_cb_(lv_disp_drv_t *disp_drv, const lv_area_t *area, lv_color_t *color_p);
+  std::vector<display::Display *> displays_{};
+  lv_disp_draw_buf_t draw_buf_{};
+  lv_disp_drv_t disp_drv_{};
+  lv_disp_t *disp_{};
+
+  std::vector<std::function<void(lv_disp_t *)>> init_lambdas_;
+  size_t buffer_frac_{1};
+  bool full_refresh_{};
+};
+
+}  // namespace lvgl
+}  // namespace esphome
+
+#endif

esphome/components/lvgl/lvgl_hal.h

@@ -0,0 +1,21 @@
+//
+// Created by Clyde Stubbs on 20/9/2023.
+//
+
+#pragma once
+
+#ifdef __cplusplus
+#define EXTERNC extern "C"
+#include <cstddef>
+namespace esphome {
+namespace lvgl {}
+}  // namespace esphome
+#else
+#define EXTERNC extern
+#include <stddef.h>
+#endif
+
+EXTERNC size_t lv_millis(void);
+EXTERNC void *lv_custom_mem_alloc(size_t size);
+EXTERNC void lv_custom_mem_free(void *ptr);
+EXTERNC void *lv_custom_mem_realloc(void *ptr, size_t size);

esphome/components/lvgl/obj.py

@@ -0,0 +1,22 @@
+from .defines import CONF_OBJ
+from .types import lv_obj_t
+from .widget import WidgetType
+
+
+class ObjType(WidgetType):
+    """
+    The base LVGL object. All other widgets inherit from this.
+    """
+
+    def __init__(self):
+        super().__init__(CONF_OBJ, schema={}, modify_schema={})
+
+    @property
+    def w_type(self):
+        return lv_obj_t
+
+    async def to_code(self, w, config):
+        return []
+
+
+obj_spec = ObjType()

esphome/components/lvgl/schemas.py

@@ -0,0 +1,260 @@
+from esphome import config_validation as cv
+from esphome.const import CONF_ARGS, CONF_FORMAT, CONF_ID, CONF_STATE, CONF_TYPE
+from esphome.schema_extractors import SCHEMA_EXTRACT
+
+from . import defines as df, lv_validation as lvalid, types as ty
+from .defines import WIDGET_PARTS
+from .helpers import (
+    REQUIRED_COMPONENTS,
+    add_lv_use,
+    requires_component,
+    validate_printf,
+)
+from .lv_validation import lv_font
+from .types import WIDGET_TYPES, get_widget_type
+
+# A schema for text properties
+TEXT_SCHEMA = cv.Schema(
+    {
+        cv.Optional(df.CONF_TEXT): cv.Any(
+            cv.All(
+                cv.Schema(
+                    {
+                        cv.Required(CONF_FORMAT): cv.string,
+                        cv.Optional(CONF_ARGS, default=list): cv.ensure_list(
+                            cv.lambda_
+                        ),
+                    },
+                ),
+                validate_printf,
+            ),
+            lvalid.lv_text,
+        )
+    }
+)
+
+# All LVGL styles and their validators
+STYLE_PROPS = {
+    "align": df.CHILD_ALIGNMENTS.one_of,
+    "arc_opa": lvalid.opacity,
+    "arc_color": lvalid.lv_color,
+    "arc_rounded": lvalid.lv_bool,
+    "arc_width": cv.positive_int,
+    "anim_time": lvalid.lv_milliseconds,
+    "bg_color": lvalid.lv_color,
+    "bg_grad_color": lvalid.lv_color,
+    "bg_dither_mode": df.LvConstant("LV_DITHER_", "NONE", "ORDERED", "ERR_DIFF").one_of,
+    "bg_grad_dir": df.LvConstant("LV_GRAD_DIR_", "NONE", "HOR", "VER").one_of,
+    "bg_grad_stop": lvalid.stop_value,
+    "bg_img_opa": lvalid.opacity,
+    "bg_img_recolor": lvalid.lv_color,
+    "bg_img_recolor_opa": lvalid.opacity,
+    "bg_main_stop": lvalid.stop_value,
+    "bg_opa": lvalid.opacity,
+    "border_color": lvalid.lv_color,
+    "border_opa": lvalid.opacity,
+    "border_post": lvalid.lv_bool,
+    "border_side": df.LvConstant(
+        "LV_BORDER_SIDE_", "NONE", "TOP", "BOTTOM", "LEFT", "RIGHT", "INTERNAL"
+    ).several_of,
+    "border_width": cv.positive_int,
+    "clip_corner": lvalid.lv_bool,
+    "height": lvalid.size,
+    "img_recolor": lvalid.lv_color,
+    "img_recolor_opa": lvalid.opacity,
+    "line_width": cv.positive_int,
+    "line_dash_width": cv.positive_int,
+    "line_dash_gap": cv.positive_int,
+    "line_rounded": lvalid.lv_bool,
+    "line_color": lvalid.lv_color,
+    "opa": lvalid.opacity,
+    "opa_layered": lvalid.opacity,
+    "outline_color": lvalid.lv_color,
+    "outline_opa": lvalid.opacity,
+    "outline_pad": lvalid.size,
+    "outline_width": lvalid.size,
+    "pad_all": lvalid.size,
+    "pad_bottom": lvalid.size,
+    "pad_column": lvalid.size,
+    "pad_left": lvalid.size,
+    "pad_right": lvalid.size,
+    "pad_row": lvalid.size,
+    "pad_top": lvalid.size,
+    "shadow_color": lvalid.lv_color,
+    "shadow_ofs_x": cv.int_,
+    "shadow_ofs_y": cv.int_,
+    "shadow_opa": lvalid.opacity,
+    "shadow_spread": cv.int_,
+    "shadow_width": cv.positive_int,
+    "text_align": df.LvConstant(
+        "LV_TEXT_ALIGN_", "LEFT", "CENTER", "RIGHT", "AUTO"
+    ).one_of,
+    "text_color": lvalid.lv_color,
+    "text_decor": df.LvConstant(
+        "LV_TEXT_DECOR_", "NONE", "UNDERLINE", "STRIKETHROUGH"
+    ).several_of,
+    "text_font": lv_font,
+    "text_letter_space": cv.positive_int,
+    "text_line_space": cv.positive_int,
+    "text_opa": lvalid.opacity,
+    "transform_angle": lvalid.angle,
+    "transform_height": lvalid.pixels_or_percent,
+    "transform_pivot_x": lvalid.pixels_or_percent,
+    "transform_pivot_y": lvalid.pixels_or_percent,
+    "transform_zoom": lvalid.zoom,
+    "translate_x": lvalid.pixels_or_percent,
+    "translate_y": lvalid.pixels_or_percent,
+    "max_height": lvalid.pixels_or_percent,
+    "max_width": lvalid.pixels_or_percent,
+    "min_height": lvalid.pixels_or_percent,
+    "min_width": lvalid.pixels_or_percent,
+    "radius": cv.Any(lvalid.size, df.LvConstant("LV_RADIUS_", "CIRCLE").one_of),
+    "width": lvalid.size,
+    "x": lvalid.pixels_or_percent,
+    "y": lvalid.pixels_or_percent,
+}
+
+# Complete object style schema
+STYLE_SCHEMA = cv.Schema({cv.Optional(k): v for k, v in STYLE_PROPS.items()}).extend(
+    {
+        cv.Optional(df.CONF_SCROLLBAR_MODE): df.LvConstant(
+            "LV_SCROLLBAR_MODE_", "OFF", "ON", "ACTIVE", "AUTO"
+        ).one_of,
+    }
+)
+
+# Object states. Top level properties apply to MAIN
+STATE_SCHEMA = cv.Schema(
+    {cv.Optional(state): STYLE_SCHEMA for state in df.STATES}
+).extend(STYLE_SCHEMA)
+# Setting object states
+SET_STATE_SCHEMA = cv.Schema(
+    {cv.Optional(state): lvalid.lv_bool for state in df.STATES}
+)
+# Setting object flags
+FLAG_SCHEMA = cv.Schema({cv.Optional(flag): cv.boolean for flag in df.OBJ_FLAGS})
+FLAG_LIST = cv.ensure_list(df.LvConstant("LV_OBJ_FLAG_", *df.OBJ_FLAGS).one_of)
+
+
+def part_schema(widget_type):
+    """
+    Generate a schema for the various parts (e.g. main:, indicator:) of a widget type
+    :param widget_type:  The type of widget to generate for
+    :return:
+    """
+    parts = WIDGET_PARTS.get(widget_type)
+    if parts is None:
+        parts = (df.CONF_MAIN,)
+    return cv.Schema({cv.Optional(part): STATE_SCHEMA for part in parts}).extend(
+        STATE_SCHEMA
+    )
+
+
+def obj_schema(widget_type: str):
+    """
+    Create a schema for a widget type itself i.e. no allowance for children
+    :param widget_type:
+    :return:
+    """
+    return (
+        part_schema(widget_type)
+        .extend(FLAG_SCHEMA)
+        .extend(ALIGN_TO_SCHEMA)
+        .extend(
+            cv.Schema(
+                {
+                    cv.Optional(CONF_STATE): SET_STATE_SCHEMA,
+                }
+            )
+        )
+    )
+
+
+ALIGN_TO_SCHEMA = {
+    cv.Optional(df.CONF_ALIGN_TO): cv.Schema(
+        {
+            cv.Required(CONF_ID): cv.use_id(ty.lv_obj_t),
+            cv.Required(df.CONF_ALIGN): df.ALIGN_ALIGNMENTS.one_of,
+            cv.Optional(df.CONF_X, default=0): lvalid.pixels_or_percent,
+            cv.Optional(df.CONF_Y, default=0): lvalid.pixels_or_percent,
+        }
+    )
+}
+
+
+# A style schema that can include text
+STYLED_TEXT_SCHEMA = cv.maybe_simple_value(
+    STYLE_SCHEMA.extend(TEXT_SCHEMA), key=df.CONF_TEXT
+)
+
+
+ALL_STYLES = {
+    **STYLE_PROPS,
+}
+
+
+def container_validator(schema, widget_type):
+    """
+    Create a validator for a container given the widget type
+    :param schema: Base schema to extend
+    :param widget_type:
+    :return:
+    """
+
+    def validator(value):
+        result = schema
+        if w_sch := WIDGET_TYPES[widget_type].schema:
+            result = result.extend(w_sch)
+        if value and (layout := value.get(df.CONF_LAYOUT)):
+            if not isinstance(layout, dict):
+                raise cv.Invalid("Layout value must be a dict")
+            ltype = layout.get(CONF_TYPE)
+            add_lv_use(ltype)
+        if value == SCHEMA_EXTRACT:
+            return result
+        return result(value)
+
+    return validator
+
+
+def container_schema(widget_type, extras=None):
+    """
+    Create a schema for a container widget of a given type. All obj properties are available, plus
+    the extras passed in, plus any defined for the specific widget being specified.
+    :param widget_type:     The widget type, e.g. "img"
+    :param extras:  Additional options to be made available, e.g. layout properties for children
+    :return: The schema for this type of widget.
+    """
+    lv_type = get_widget_type(widget_type)
+    schema = obj_schema(widget_type).extend({cv.GenerateID(): cv.declare_id(lv_type)})
+    if extras:
+        schema = schema.extend(extras)
+    # Delayed evaluation for recursion
+    return container_validator(schema, widget_type)
+
+
+def widget_schema(widget_type, extras=None):
+    """
+    Create a schema for a given widget type
+    :param widget_type: The name of the widget
+    :param extras:
+    :return:
+    """
+    validator = container_schema(widget_type, extras=extras)
+    if required := REQUIRED_COMPONENTS.get(widget_type):
+        validator = cv.All(validator, requires_component(required))
+    return cv.Exclusive(widget_type, df.CONF_WIDGETS), validator
+
+
+# All widget schemas must be defined before this is called.
+
+
+def any_widget_schema(extras=None):
+    """
+    Generate schemas for all possible LVGL widgets. This is what implements the ability to have a list of any kind of
+    widget under the widgets: key.
+
+    :param extras: Additional schema to be applied to each generated one
+    :return:
+    """
+    return cv.Any(dict(widget_schema(wt, extras) for wt in WIDGET_PARTS))

esphome/components/lvgl/types.py

@@ -0,0 +1,64 @@
+from esphome import codegen as cg
+from esphome.core import ID
+
+from .defines import CONF_LABEL, CONF_OBJ, CONF_TEXT
+
+uint16_t_ptr = cg.uint16.operator("ptr")
+lvgl_ns = cg.esphome_ns.namespace("lvgl")
+char_ptr = cg.global_ns.namespace("char").operator("ptr")
+void_ptr = cg.void.operator("ptr")
+LvglComponent = lvgl_ns.class_("LvglComponent", cg.PollingComponent)
+lv_event_code_t = cg.global_ns.namespace("lv_event_code_t")
+FontEngine = lvgl_ns.class_("FontEngine")
+LvCompound = lvgl_ns.class_("LvCompound")
+lv_font_t = cg.global_ns.class_("lv_font_t")
+lv_style_t = cg.global_ns.struct("lv_style_t")
+lv_pseudo_button_t = lvgl_ns.class_("LvPseudoButton")
+lv_obj_base_t = cg.global_ns.class_("lv_obj_t", lv_pseudo_button_t)
+lv_obj_t_ptr = lv_obj_base_t.operator("ptr")
+lv_disp_t_ptr = cg.global_ns.struct("lv_disp_t").operator("ptr")
+lv_color_t = cg.global_ns.struct("lv_color_t")
+
+
+# this will be populated later, in __init__.py to avoid circular imports.
+WIDGET_TYPES: dict = {}
+
+
+class LvType(cg.MockObjClass):
+    def __init__(self, *args, **kwargs):
+        parens = kwargs.pop("parents", ())
+        super().__init__(*args, parents=parens + (lv_obj_base_t,))
+        self.args = kwargs.pop("largs", [(lv_obj_t_ptr, "obj")])
+        self.value = kwargs.pop("lvalue", lambda w: w.obj)
+        self.has_on_value = kwargs.pop("has_on_value", False)
+        self.value_property = None
+
+    def get_arg_type(self):
+        return self.args[0][0] if len(self.args) else None
+
+
+class LvText(LvType):
+    def __init__(self, *args, **kwargs):
+        super().__init__(
+            *args,
+            largs=[(cg.std_string, "text")],
+            lvalue=lambda w: w.get_property("text")[0],
+            **kwargs,
+        )
+        self.value_property = CONF_TEXT
+
+
+lv_obj_t = LvType("lv_obj_t")
+lv_label_t = LvText("lv_label_t")
+
+LV_TYPES = {
+    CONF_LABEL: lv_label_t,
+    CONF_OBJ: lv_obj_t,
+}
+
+
+def get_widget_type(typestr: str) -> LvType:
+    return LV_TYPES[typestr]
+
+
+CUSTOM_EVENT = ID("lv_custom_event", False, type=lv_event_code_t)

esphome/components/lvgl/widget.py

@@ -0,0 +1,347 @@
+import sys
+from typing import Any
+
+from esphome import codegen as cg, config_validation as cv
+from esphome.config_validation import Invalid
+from esphome.const import CONF_GROUP, CONF_ID, CONF_STATE
+from esphome.core import ID, TimePeriod
+from esphome.coroutine import FakeAwaitable
+from esphome.cpp_generator import MockObjClass
+
+from .defines import (
+    CONF_DEFAULT,
+    CONF_MAIN,
+    CONF_SCROLLBAR_MODE,
+    CONF_WIDGETS,
+    OBJ_FLAGS,
+    PARTS,
+    STATES,
+    LValidator,
+    join_enums,
+)
+from .helpers import add_lv_use
+from .lvcode import ConstantLiteral, add_line_marks, lv, lv_add, lv_assign, lv_obj
+from .schemas import ALL_STYLES
+from .types import WIDGET_TYPES, LvCompound, lv_obj_t
+
+EVENT_LAMB = "event_lamb__"
+
+
+class WidgetType:
+    """
+    Describes a type of Widget, e.g. "bar" or "line"
+    """
+
+    def __init__(self, name, schema=None, modify_schema=None):
+        """
+        :param name: The widget name, e.g. "bar"
+        :param schema: The config schema for defining a widget
+        :param modify_schema: A schema to update the widget
+        """
+        self.name = name
+        self.schema = schema or {}
+        if modify_schema is None:
+            self.modify_schema = schema
+        else:
+            self.modify_schema = modify_schema
+
+    @property
+    def animated(self):
+        return False
+
+    @property
+    def w_type(self):
+        """
+        Get the type associated with this widget
+        :return:
+        """
+        return lv_obj_t
+
+    def is_compound(self):
+        return self.w_type.inherits_from(LvCompound)
+
+    async def to_code(self, w, config: dict):
+        """
+        Generate code for a given widget
+        :param w: The widget
+        :param config: Its configuration
+        :return: Generated code as a list of text lines
+        """
+        raise NotImplementedError(f"No to_code defined for {self.name}")
+
+    def obj_creator(self, parent: MockObjClass, config: dict):
+        """
+        Create an instance of the widget type
+        :param parent: The parent to which it should be attached
+        :param config:  Its configuration
+        :return: Generated code as a single text line
+        """
+        return f"lv_{self.name}_create({parent})"
+
+    def get_uses(self):
+        """
+        Get a list of other widgets used by this one
+        :return:
+        """
+        return ()
+
+
+class LvScrActType(WidgetType):
+    """
+    A "widget" representing the active screen.
+    """
+
+    def __init__(self):
+        super().__init__("lv_scr_act()")
+
+    def obj_creator(self, parent: MockObjClass, config: dict):
+        return []
+
+    async def to_code(self, w, config: dict):
+        return []
+
+
+class Widget:
+    """
+    Represents a Widget.
+    """
+
+    widgets_completed = False
+
+    @staticmethod
+    def set_completed():
+        Widget.widgets_completed = True
+
+    def __init__(self, var, wtype: WidgetType, config: dict = None, parent=None):
+        self.var = var
+        self.type = wtype
+        self.config = config
+        self.scale = 1.0
+        self.step = 1.0
+        self.range_from = -sys.maxsize
+        self.range_to = sys.maxsize
+        self.parent = parent
+
+    @staticmethod
+    def create(name, var, wtype: WidgetType, config: dict = None, parent=None):
+        w = Widget(var, wtype, config, parent)
+        if name is not None:
+            widget_map[name] = w
+        return w
+
+    @property
+    def obj(self):
+        if self.type.is_compound():
+            return f"{self.var}->obj"
+        return self.var
+
+    def add_state(self, *args):
+        return lv_obj.add_state(self.obj, *args)
+
+    def clear_state(self, *args):
+        return lv_obj.clear_state(self.obj, *args)
+
+    def add_flag(self, *args):
+        return lv_obj.add_flag(self.obj, *args)
+
+    def clear_flag(self, *args):
+        return lv_obj.clear_flag(self.obj, *args)
+
+    def set_property(self, prop, value, animated: bool = None, ltype=None):
+        if isinstance(value, dict):
+            value = value.get(prop)
+        if value is None:
+            return
+        if isinstance(value, TimePeriod):
+            value = value.total_milliseconds
+        ltype = ltype or self.__type_base()
+        if animated is None or self.type.animated is not True:
+            lv.call(f"{ltype}_set_{prop}", self.obj, value)
+        else:
+            lv.call(
+                f"{ltype}_set_{prop}",
+                self.obj,
+                value,
+                "LV_ANIM_ON" if animated else "LV_ANIM_OFF",
+            )
+
+    def get_property(self, prop, ltype=None):
+        ltype = ltype or self.__type_base()
+        return f"lv_{ltype}_get_{prop}({self.obj})"
+
+    def set_style(self, prop, value, state):
+        if value is None:
+            return []
+        return lv.call(f"obj_set_style_{prop}", self.obj, value, state)
+
+    def __type_base(self):
+        wtype = self.type.w_type
+        base = str(wtype)
+        if base.startswith("Lv"):
+            return f"{wtype}".removeprefix("Lv").removesuffix("Type").lower()
+        return f"{wtype}".removeprefix("lv_").removesuffix("_t")
+
+    def __str__(self):
+        return f"({self.var}, {self.type})"
+
+
+# Map of widgets to their config, used for trigger generation
+widget_map: dict[Any, Widget] = {}
+
+
+def get_widget_generator(wid):
+    """
+    Used to wait for a widget during code generation.
+    :param wid:
+    :return:
+    """
+    while True:
+        if obj := widget_map.get(wid):
+            return obj
+        if Widget.widgets_completed:
+            raise Invalid(
+                f"Widget {wid} not found, yet all widgets should be defined by now"
+            )
+        yield
+
+
+async def get_widget(wid: ID) -> Widget:
+    if obj := widget_map.get(wid):
+        return obj
+    return await FakeAwaitable(get_widget_generator(wid))
+
+
+def collect_props(config):
+    """
+    Collect all properties from a configuration
+    :param config:
+    :return:
+    """
+    props = {}
+    for prop in [*ALL_STYLES, *OBJ_FLAGS, CONF_GROUP]:
+        if prop in config:
+            props[prop] = config[prop]
+    return props
+
+
+def collect_states(config):
+    """
+    Collect prperties for each state of a widget
+    :param config:
+    :return:
+    """
+    states = {CONF_DEFAULT: collect_props(config)}
+    for state in STATES:
+        if state in config:
+            states[state] = collect_props(config[state])
+    return states
+
+
+def collect_parts(config):
+    """
+    Collect properties and states for all widget parts
+    :param config:
+    :return:
+    """
+    parts = {CONF_MAIN: collect_states(config)}
+    for part in PARTS:
+        if part in config:
+            parts[part] = collect_states(config[part])
+    return parts
+
+
+async def set_obj_properties(w: Widget, config):
+    """Generate a list of C++ statements to apply properties to an lv_obj_t"""
+    parts = collect_parts(config)
+    for part, states in parts.items():
+        for state, props in states.items():
+            lv_state = ConstantLiteral(
+                f"(int)LV_STATE_{state.upper()}|(int)LV_PART_{part.upper()}"
+            )
+            for prop, value in {
+                k: v for k, v in props.items() if k in ALL_STYLES
+            }.items():
+                if isinstance(ALL_STYLES[prop], LValidator):
+                    value = await ALL_STYLES[prop].process(value)
+                w.set_style(prop, value, lv_state)
+    flag_clr = set()
+    flag_set = set()
+    props = parts[CONF_MAIN][CONF_DEFAULT]
+    for prop, value in {k: v for k, v in props.items() if k in OBJ_FLAGS}.items():
+        if value:
+            flag_set.add(prop)
+        else:
+            flag_clr.add(prop)
+    if flag_set:
+        adds = join_enums(flag_set, "LV_OBJ_FLAG_")
+        w.add_flag(adds)
+    if flag_clr:
+        clrs = join_enums(flag_clr, "LV_OBJ_FLAG_")
+        w.clear_flag(clrs)
+
+    if states := config.get(CONF_STATE):
+        adds = set()
+        clears = set()
+        lambs = {}
+        for key, value in states.items():
+            if isinstance(value, cv.Lambda):
+                lambs[key] = value
+            elif value == "true":
+                adds.add(key)
+            else:
+                clears.add(key)
+        if adds:
+            adds = ConstantLiteral(join_enums(adds, "LV_STATE_"))
+            w.add_state(adds)
+        if clears:
+            clears = ConstantLiteral(join_enums(clears, "LV_STATE_"))
+            w.clear_state(clears)
+        for key, value in lambs.items():
+            lamb = await cg.process_lambda(value, [], return_type=cg.bool_)
+            state = ConstantLiteral(f"LV_STATE_{key.upper}")
+            lv.cond_if(lamb)
+            w.add_state(state)
+            lv.cond_else()
+            w.clear_state(state)
+            lv.cond_endif()
+    if scrollbar_mode := config.get(CONF_SCROLLBAR_MODE):
+        lv_obj.set_scrollbar_mode(w.obj, scrollbar_mode)
+
+
+async def add_widgets(parent: Widget, config: dict):
+    """
+    Add all widgets to an object
+    :param parent: The enclosing obj
+    :param config: The configuration
+    :return:
+    """
+    for w in config.get(CONF_WIDGETS) or ():
+        w_type, w_cnfig = next(iter(w.items()))
+        await widget_to_code(w_cnfig, w_type, parent.obj)
+
+
+async def widget_to_code(w_cnfig, w_type, parent):
+    """
+    Converts a Widget definition to C code.
+    :param w_cnfig: The widget configuration
+    :param w_type:  The Widget type
+    :param parent: The parent to which the widget should be added
+    :return:
+    """
+    spec: WidgetType = WIDGET_TYPES[w_type]
+    creator = spec.obj_creator(parent, w_cnfig)
+    add_lv_use(spec.name)
+    add_lv_use(*spec.get_uses())
+    wid = w_cnfig[CONF_ID]
+    add_line_marks(wid)
+    if spec.is_compound():
+        var = cg.new_Pvariable(wid)
+        lv_add(var.set_obj(creator))
+    else:
+        var = cg.Pvariable(wid, cg.nullptr, type_=lv_obj_t)
+        lv_assign(var, creator)
+
+    widget = Widget.create(wid, var, spec, w_cnfig, parent)
+    await set_obj_properties(widget, w_cnfig)
+    await add_widgets(widget, w_cnfig)
+    await spec.to_code(widget, w_cnfig)

esphome/core/defines.h

@@ -38,6 +38,9 @@
 #define USE_LIGHT
 #define USE_LOCK
 #define USE_LOGGER
+#define USE_LVGL
+#define USE_LVGL_FONT
+#define USE_LVGL_IMAGE
 #define USE_MDNS
 #define USE_MEDIA_PLAYER
 #define USE_MQTT

platformio.ini

@@ -42,6 +42,7 @@ lib_deps =
     pavlodn/HaierProtocol@0.9.31           ; haier
     ; This is using the repository until a new release is published to PlatformIO
     https://github.com/Sensirion/arduino-gas-index-algorithm.git#3.2.1 ; Sensirion Gas Index Algorithm Arduino Library
+    lvgl/lvgl@8.4.0                                       ; lvgl
 build_flags =
     -DESPHOME_LOG_LEVEL=ESPHOME_LOG_LEVEL_VERY_VERBOSE
 src_filter =

tests/components/lvgl/lvgl-package.yaml

@@ -0,0 +1,24 @@
+color:
+  - id: light_blue
+    hex: "3340FF"
+
+lvgl:
+  bg_color: light_blue
+  widgets:
+    - label:
+        text: Hello world
+        text_color: 0xFF8000
+        align: center
+        text_font: montserrat_40
+        border_post: true
+
+    - label:
+        text: "Hello shiny day"
+        text_color: 0xFFFFFF
+        align: bottom_mid
+        text_font: space16
+
+font:
+  - file: "gfonts://Roboto"
+    id: space16
+    bpp: 4

tests/components/lvgl/test.esp32-ard.yaml

@@ -0,0 +1,30 @@
+spi:
+  clk_pin: 14
+  mosi_pin: 13
+
+i2c:
+  sda: GPIO18
+  scl: GPIO19
+
+display:
+  - platform: ili9xxx
+    model: st7789v
+    id: tft_display
+    dimensions:
+      width: 240
+      height: 320
+    transform:
+      swap_xy: false
+      mirror_x: true
+      mirror_y: true
+    data_rate: 80MHz
+    cs_pin: GPIO22
+    dc_pin: GPIO21
+    auto_clear_enabled: false
+    invert_colors: false
+    update_interval: never
+
+packages:
+  lvgl: !include lvgl-package.yaml
+
+<<: !include common.yaml

tests/components/lvgl/test.esp32-idf.yaml

@@ -0,0 +1,52 @@
+spi:
+  clk_pin: 14
+  mosi_pin: 13
+
+i2c:
+  sda: GPIO18
+  scl: GPIO19
+
+display:
+  - platform: ili9xxx
+    model: st7789v
+    id: second_display
+    dimensions:
+      width: 240
+      height: 320
+    transform:
+      swap_xy: false
+      mirror_x: true
+      mirror_y: true
+    data_rate: 80MHz
+    cs_pin: GPIO20
+    dc_pin: GPIO15
+    auto_clear_enabled: false
+    invert_colors: false
+    update_interval: never
+
+  - platform: ili9xxx
+    model: st7789v
+    id: tft_display
+    dimensions:
+      width: 240
+      height: 320
+    transform:
+      swap_xy: false
+      mirror_x: true
+      mirror_y: true
+    data_rate: 80MHz
+    cs_pin: GPIO22
+    dc_pin: GPIO21
+    auto_clear_enabled: false
+    invert_colors: false
+    update_interval: never
+
+packages:
+  lvgl: !include lvgl-package.yaml
+
+lvgl:
+  displays:
+    - tft_display
+    - second_display
+
+<<: !include common.yaml