Use this skill when working with the Phaser 4 event system. Covers EventEmitter, scene events, game events, custom events, and event-driven communication. Triggers on: events, on, emit, EventEmitter, scene events, listeners.

Events System Phaser uses the EventEmitter pattern (via eventemitter3) throughout the entire framework. Every major system Game, Scene, Input, Loader, Cameras, Sound, Tweens, Physics, Textures, Animations is an EventEmitter or contains one. Events use lowercase string keys. Phaser provides named constants for all built in events to avoid typos and enable IDE autocomplete. Key source paths: src/events/EventEmitter.js , src/scene/events/ , src/core/events/ , src/input/events/ , src/loader/events/ , src/animations/events/ , src/cameras/2d/events/ , src/sound/events/ , src/tweens/events/ , src/physics/arcade/events/ , src/textures/events/ , src/gameobjects/events/ , src/time/events/ Related skills: ../scenes/SKILL.md, ../input keyboard mouse touch/SKILL.md Quick Start Using Named Constants (Preferred) Core Concepts EventEmitter Base Class Phaser.Events.EventEmitter extends eventemitter3. It adds shutdown() and destroy() methods that both call removeAllListeners() . Full API (inherited from eventemitter3): Method Description on(event, fn, context?) Add persistent listener. Returns this for chaining addListener(event, fn, context?) Alias for on once(event, fn, context?) Add one time listener; auto removed after first fire off(event, fn?, context?, once?) Remove listener(s). Must pass same fn reference to remove specific listener removeListener(event, fn?, context?, once?) Alias for off removeAllListeners(event?) Remove all listeners for event, or all events if no arg emit(event, ...args) Fire event. Returns true if it had listeners listeners(event) Return array of listener functions for an event listenerCount(event) Return number of listeners for an event eventNames() Return array of event names that have listeners shutdown() Calls removeAllListeners() destroy() Calls removeAllListeners() Event Strings vs Constants Every built in event is a lowercase string exported as a constant. The constant name maps predictably to the string: Some events use a key suffix pattern for per key listening: Context (Third Argument) The third argument to on / once sets this inside the callback. Defaults to the emitter. Common Patterns Scene Lifecycle Events Frame loop order: preupdate update Scene.update() postupdate prerender render Game Level Events Inter Scene Communication Custom Events All Event Namespaces Reference Scene Events ( Phaser.Scenes.Events ) Emitter: this.events (the Scene's Systems EventEmitter) Constant String When BOOT 'boot' Scene Systems boot (for plugins) READY 'ready' Scene Systems fully ready START 'start' Scene starts running CREATE 'create' After Scene.create() completes PRE UPDATE 'preupdate' Before update each frame UPDATE 'update' Main update each frame POST UPDATE 'postupdate' After update each frame PRE RENDER 'prerender' Before render each frame RENDER 'render' During render each frame PAUSE 'pause' Scene paused RESUME 'resume' Scene resumed from pause SLEEP 'sleep' Scene put to sleep WAKE 'wake' Scene woken from sleep SHUTDOWN 'shutdown' Scene shutting down (may restart) DESTROY 'destroy' Scene permanently destroyed ADDED TO SCENE 'addedtoscene' GameObject added to scene REMOVED FROM SCENE 'removedfromscene' GameObject removed from scene TRANSITION INIT 'transitioninit' Transition initialized (target scene) TRANSITION START 'transitionstart' Transition started (target scene) TRANSITION OUT 'transitionout' Transition out (source scene) TRANSITION COMPLETE 'transitioncomplete' Transition finished TRANSITION WAKE 'transitionwake' Transition wakes target scene Game Events ( Phaser.Core.Events ) Emitter: this.game.events or game.events Constant String When BOOT 'boot' Game instance finished booting READY 'ready' Game ready to start running SYSTEM READY 'systemready' All global systems ready PRE STEP 'prestep' Before game loop step STEP 'step' Main game loop step POST STEP 'poststep' After game loop step PRE RENDER 'prerender' Before rendering all scenes POST RENDER 'postrender' After rendering all scenes PAUSE 'pause' Game paused RESUME 'resume' Game resumed BLUR 'blur' Browser tab lost focus FOCUS 'focus' Browser tab gained focus HIDDEN 'hidden' Page Visibility API: hidden VISIBLE 'visible' Page Visibility API: visible CONTEXT LOST 'contextlost' WebGL context lost DESTROY 'destroy' Game being destroyed Input Events ( Phaser.Input.Events ) Emitter: this.input (scene level) or individual GameObjects. Events exist at three levels: scene level ( this.input ), scene level with gameobject prefix, and directly on interactive GameObjects. See ../input keyboard mouse touch/SKILL.md for full usage. Scene level pointer events (on this.input ): POINTER DOWN 'pointerdown' POINTER UP 'pointerup' POINTER MOVE 'pointermove' POINTER OVER 'pointerover' POINTER OUT 'pointerout' POINTER WHEEL 'wheel' POINTER DOWN OUTSIDE 'pointerdownoutside' POINTER UP OUTSIDE 'pointerupoutside' Scene level gameobject events (on this.input ): GAMEOBJECT DOWN 'gameobjectdown' GAMEOBJECT UP 'gameobjectup' GAMEOBJECT MOVE 'gameobjectmove' GAMEOBJECT OVER 'gameobjectover' GAMEOBJECT OUT 'gameobjectout' GAMEOBJECT WHEEL 'gameobjectwheel' Per GameObject events (emitted on the GameObject itself, requires setInteractive() ): GAMEOBJECT POINTER DOWN 'pointerdown' GAMEOBJECT POINTER UP 'pointerup' GAMEOBJECT POINTER MOVE 'pointermove' GAMEOBJECT POINTER OVER 'pointerover' GAMEOBJECT POINTER OUT 'pointerout' GAMEOBJECT POINTER WHEEL 'wheel' Drag events (on this.input and on GameObjects with same string): DRAG START / GAMEOBJECT DRAG START 'dragstart' DRAG / GAMEOBJECT DRAG 'drag' DRAG END / GAMEOBJECT DRAG END 'dragend' DRAG ENTER / GAMEOBJECT DRAG ENTER 'dragenter' DRAG OVER / GAMEOBJECT DRAG OVER 'dragover' DRAG LEAVE / GAMEOBJECT DRAG LEAVE 'dragleave' DROP / GAMEOBJECT DROP 'drop' Other: GAME OUT 'gameout' GAME OVER 'gameover' POINTERLOCK CHANGE 'pointerlockchange' Loader Events ( Phaser.Loader.Events ) Emitter: this.load Constant String When ADD 'addfile' File added to load queue START 'start' Loader starts PROGRESS 'progress' Overall progress updated (0 1) FILE LOAD 'load' Individual file loaded FILE PROGRESS 'fileprogress' Individual file progress FILE COMPLETE 'filecomplete' Individual file completed processing FILE KEY COMPLETE 'filecomplete ' Specific file completed (append type key ) FILE LOAD ERROR 'loaderror' File failed to load POST PROCESS 'postprocess' All files loaded, post processing COMPLETE 'complete' All loading complete Animation Events ( Phaser.Animations.Events ) Emitter: individual sprites (per sprite) or this.anims (global AnimationManager) Constant String When ADD ANIMATION 'add' Animation added to manager REMOVE ANIMATION 'remove' Animation removed from manager PAUSE ALL 'pauseall' All animations paused RESUME ALL 'resumeall' All animations resumed ANIMATION START 'animationstart' Animation starts playing on a sprite ANIMATION RESTART 'animationrestart' Animation restarts on a sprite ANIMATION REPEAT 'animationrepeat' Animation repeats on a sprite ANIMATION UPDATE 'animationupdate' Animation frame changes on a sprite ANIMATION COMPLETE 'animationcomplete' Animation finishes on a sprite ANIMATION COMPLETE KEY 'animationcomplete ' Specific animation finishes (append key) ANIMATION STOP 'animationstop' Animation stopped on a sprite Camera Events ( Phaser.Cameras.Scene2D.Events ) Emitter: individual camera instance (e.g. this.cameras.main ). Each camera effect has a START and COMPLETE pair. DESTROY 'cameradestroy' FADE IN START 'camerafadeinstart' FADE IN COMPLETE 'camerafadeincomplete' FADE OUT START 'camerafadeoutstart' FADE OUT COMPLETE 'camerafadeoutcomplete' FLASH START 'cameraflashstart' FLASH COMPLETE 'cameraflashcomplete' PAN START 'camerapanstart' PAN COMPLETE 'camerapancomplete' ROTATE START 'camerarotatestart' ROTATE COMPLETE 'camerarotatecomplete' SHAKE START 'camerashakestart' SHAKE COMPLETE 'camerashakecomplete' ZOOM START 'camerazoomstart' ZOOM COMPLETE 'camerazoomcomplete' FOLLOW UPDATE 'followupdate' PRE RENDER 'prerender' POST RENDER 'postrender' Sound Events ( Phaser.Sound.Events ) Emitter: individual sound instances or this.sound (SoundManager) Per sound instance events: PLAY 'play' PAUSE 'pause' RESUME 'resume' STOP 'stop' COMPLETE 'complete' LOOP 'loop' LOOPED 'looped' SEEK 'seek' MUTE 'mute' VOLUME 'volume' RATE 'rate' DETUNE 'detune' PAN 'pan' DECODED 'decoded' DESTROY 'destroy' SoundManager level events (on this.sound ): GLOBAL MUTE 'mute' GLOBAL VOLUME 'volume' GLOBAL RATE 'rate' GLOBAL DETUNE 'detune' PAUSE ALL 'pauseall' RESUME ALL 'resumeall' STOP ALL 'stopall' DECODED ALL 'decodedall' UNLOCKED 'unlocked' Tween Events ( Phaser.Tweens.Events ) Emitter: individual tween instances Constant String When TWEEN ACTIVE 'active' Tween becomes active TWEEN START 'start' Tween starts first play TWEEN UPDATE 'update' Tween updates a value TWEEN YOYO 'yoyo' Tween yoyos (reverses direction) TWEEN REPEAT 'repeat' Tween repeats TWEEN LOOP 'loop' Tween loops TWEEN PAUSE 'pause' Tween paused TWEEN RESUME 'resume' Tween resumed TWEEN COMPLETE 'complete' Tween finishes TWEEN STOP 'stop' Tween stopped manually Arcade Physics Events ( Phaser.Physics.Arcade.Events ) Emitter: this.physics.world Constant String When COLLIDE 'collide' Two bodies collide OVERLAP 'overlap' Two bodies overlap TILE COLLIDE 'tilecollide' Body collides with a tile TILE OVERLAP 'tileoverlap' Body overlaps with a tile WORLD BOUNDS 'worldbounds' Body hits world boundary WORLD STEP 'worldstep' Physics world completes a step PAUSE 'pause' Physics world paused RESUME 'resume' Physics world resumed Texture Events ( Phaser.Textures.Events ) Emitter: this.textures (TextureManager) Constant String When ADD 'addtexture' Any texture added ADD KEY 'addtexture ' Specific texture added (append key) REMOVE 'removetexture' Any texture removed REMOVE KEY 'removetexture ' Specific texture removed (append key) LOAD 'onload' Texture source loaded ERROR 'onerror' Texture source load error READY 'ready' Texture manager ready GameObject Events ( Phaser.GameObjects.Events ) Emitter: individual GameObjects Constant String When ADDED TO SCENE 'addedtoscene' GameObject added to a scene REMOVED FROM SCE

events-system