Added AdvancementTabEvent

src/main/java/net/minestom/server/advancements/AdvancementAction.java

@@ -0,0 +1,7 @@
+package net.minestom.server.advancements;
+
+public enum AdvancementAction {
+
+    OPENED_TAB, CLOSED_SCREEN
+
+}

src/main/java/net/minestom/server/event/player/AdvancementTabEvent.java

@@ -0,0 +1,51 @@
+package net.minestom.server.event.player;
+
+import net.minestom.server.advancements.AdvancementAction;
+import net.minestom.server.entity.Player;
+import net.minestom.server.event.Event;
+
+/**
+ * Called when the players open the advancement screens or switch the tab
+ * and when he closes the screen
+ */
+public class AdvancementTabEvent extends Event {
+
+    private final Player player;
+    private final AdvancementAction action;
+    private final String tabId;
+
+    public AdvancementTabEvent(Player player, AdvancementAction action, String tabId) {
+        this.player = player;
+        this.action = action;
+        this.tabId = tabId;
+    }
+
+    /**
+     * Get the player responsive for the event
+     *
+     * @return the player
+     */
+    public Player getPlayer() {
+        return player;
+    }
+
+    /**
+     * Get the action
+     *
+     * @return the action
+     */
+    public AdvancementAction getAction() {
+        return action;
+    }
+
+    /**
+     * Get the tab id
+     * <p>
+     * Not null ony if {@link #getAction()} is equal to {@link AdvancementAction#OPENED_TAB}
+     *
+     * @return the tab id
+     */
+    public String getTabId() {
+        return tabId;
+    }
+}

src/main/java/net/minestom/server/listener/AdvancementTabListener.java

@@ -1,12 +1,17 @@
 package net.minestom.server.listener;
 
+import net.minestom.server.advancements.AdvancementAction;
 import net.minestom.server.entity.Player;
+import net.minestom.server.event.player.AdvancementTabEvent;
 import net.minestom.server.network.packet.client.play.ClientAdvancementTabPacket;
 
 public class AdvancementTabListener {
 
     public static void listener(ClientAdvancementTabPacket packet, Player player) {
-        // Currentely unused and don't see much usage for an API
-        // TODO: Create an Event?
+        final AdvancementAction action = packet.action;
+        final String tabId = packet.tabIdentifier;
+        AdvancementTabEvent advancementTabEvent = new AdvancementTabEvent(player, action, tabId);
+
+        player.callEvent(AdvancementTabEvent.class, advancementTabEvent);
     }
 }

src/main/java/net/minestom/server/network/packet/client/play/ClientAdvancementTabPacket.java

@@ -1,25 +1,21 @@
 package net.minestom.server.network.packet.client.play;
 
+import net.minestom.server.advancements.AdvancementAction;
 import net.minestom.server.network.packet.PacketReader;
 import net.minestom.server.network.packet.client.ClientPlayPacket;
 
 public class ClientAdvancementTabPacket extends ClientPlayPacket {
 
-    public Action action;
+    public AdvancementAction action;
     public String tabIdentifier;
 
     @Override
     public void read(PacketReader reader) {
-        this.action = Action.values()[reader.readVarInt()];
+        this.action = AdvancementAction.values()[reader.readVarInt()];
 
-        if (action == Action.OPENED_TAB) {
+        if (action == AdvancementAction.OPENED_TAB) {
             this.tabIdentifier = reader.readSizedString();
         }
     }
 
-    public enum Action {
-        OPENED_TAB,
-        CLOSED_SCREEN
-    }
-
 }