[lvgl] Allow esphome::Image in lambda to update image source directly (#7624)

esphome/components/lvgl/lvgl_esphome.h

@@ -4,6 +4,9 @@
 #ifdef USE_BINARY_SENSOR
 #include "esphome/components/binary_sensor/binary_sensor.h"
 #endif  // USE_BINARY_SENSOR
+#ifdef USE_LVGL_IMAGE
+#include "esphome/components/image/image.h"
+#endif  // USE_LVGL_IMAGE
 #ifdef USE_LVGL_ROTARY_ENCODER
 #include "esphome/components/rotary_encoder/rotary_encoder.h"
 #endif  // USE_LVGL_ROTARY_ENCODER
@@ -47,6 +50,14 @@ static const display::ColorBitness LV_BITNESS = display::ColorBitness::COLOR_BIT
 static const display::ColorBitness LV_BITNESS = display::ColorBitness::COLOR_BITNESS_332;
 #endif  // LV_COLOR_DEPTH
 
+#ifdef USE_LVGL_IMAGE
+// Shortcut / overload, so that the source of an image can easily be updated
+// from within a lambda.
+inline void lv_img_set_src(lv_obj_t *obj, esphome::image::Image *image) {
+  lv_img_set_src(obj, image->get_lv_img_dsc());
+}
+#endif  // USE_LVGL_IMAGE
+
 // Parent class for things that wrap an LVGL object
 class LvCompound {
  public:

tests/components/lvgl/common.yaml

@@ -127,6 +127,11 @@ binary_sensor:
   - platform: lvgl
     name: LVGL checkbox
     widget: checkbox_id
+    on_state:
+      then:
+        - lvgl.image.update:
+            id: lv_image
+            src: !lambda if (x) return id(cat_image); else return id(dog_image);
 
 wifi:
   ssid: SSID

tests/components/lvgl/lvgl-package.yaml

@@ -419,6 +419,7 @@ lvgl:
             spin_time: 2s
             align: left_mid
         - image:
+            id: lv_image
             src: cat_image
             align: top_left
             y: 50