Uncaught TypeError: Cannot read properties of undefined (reading 'isParent')

Hi all,

I’m creating a game with Phaser3 by extending the Scene and Sprite classes in separate modules file and get this error message after running it:

Uncaught TypeError: Cannot read properties of undefined (reading ‘isParent’)

at World.collideObjects (phaser.js:126291:21)
at Collider.update (phaser.js:129644:20)
at World.update (phaser.js:125511:30)
at EventEmitter.emit (phaser.js:1928:33)
at Systems.step (phaser.js:49066:16)
at SceneManager.update (phaser.js:100289:21)
at Game.step (phaser.js:162805:20)
at TimeStep.step (phaser.js:89366:14)
at step (phaser.js:89613:19)

I’ve tried searching for the solution for hours but still can’t figure it out. Here’s my JS file (i combined all the modules into one js file and stripped out the export and import statements):

//------------------------------MODULE: VARIABLES-----------------------------------
let w=640;
let h=480;

//------------------------------MODULE: BASE SCENE CLASS------------------------------------
class BaseScene extends Phaser.Scene{
	constructor(key){
		super(key);
		//this.cursor; // let the class to have ability having cursor
		//this.player; //let the class to have player character
	}
	preload(){
		// in the child class, call this by using super.preload();
	}
	create(){
		// in the child class, call this by using super.create();
	}
	update(){
		// in the child class, call this by using super.update();	

	}
}

//--------------------------------MODULE: BASE SPRITE CLASS----------------------------------
class BaseSprite extends Phaser.Physics.Arcade.Sprite{
	constructor(scene,x,y,texture){
		super(scene,x,y,texture);

		//----must be altered after creating the object--//
		this.frameL={start:0,end:0};;//left    //{start:.. , end:..}
		this.frameR={start:0,end:0};;//right
		this.frameU={start:0,end:0};;//up
		this.frameD={start:0,end:0};;//down
		this.frameT={start:0,end:0};;//turn
		this.frameA={start:0,end:0};;//action
		this.baseV=300;
		this.baseJump=500;
		//---------------------//
		
		this.spriteTexture=texture;

		scene.add.existing(this); //add sprite to the scene
		scene.physics.add.existing(this); //add body to the sprite and then add it to the scene		
	}
	generateAnims(){//call this after setting frame objects
		this.anims.create({
			key:'left',
			frames:this.anims.generateFrameNumbers(this.spriteTexture,this.frameL),
			frameRate:10,
			repeat:-1
		});
		this.anims.create({
			key:'right',
			frames:this.anims.generateFrameNumbers(this.spriteTexture,this.frameR),
			frameRate:10,
			repeat:-1
		});
		this.anims.create({
			key:'up',
			frames:this.anims.generateFrameNumbers(this.spriteTexture,this.frameU),
			frameRate:10,
			repeat:-1
		});
		this.anims.create({
			key:'down',
			frames:this.anims.generateFrameNumbers(this.spriteTexture,this.frameD),
			frameRate:10,
			repeat:-1
		});
		this.anims.create({
			key:'turn',
			frames:this.anims.generateFrameNumbers(this.spriteTexture,this.frameT),
			frameRate:20
		});
		this.anims.create({
			key:'action',
			frames:this.anims.generateFrameNumbers(this.spriteTexture,this.frameA),
			frameRate:10,
			repeat:-1
		});
	}

	moveLeft(){
		this.setVelocityX(-this.baseV);
		this.anims.play('left');
	}
	moveRight(){
		this.setVelocityX(this.baseV);
		this.anims.play('right');
	}
	moveUp(){
		this.setVelocityY(-this.baseV);
		this.anims.play('up');
	}
	moveDown(){
		this.setVelocitY(this.baseV);
		this.anims.play('down');
	}
	moveJump(){
		this.setVelocityY(-this.baseJump);
		this.anims.play('up');
	}
}

//-------------------------------------MODULE: FUNCTION TO MAKE PLAYER---------------------------------------------
let makePlayer=function(scene,x,y,texture){
	let player=new BaseSprite(scene,x,y,texture);
	player.frameL={start:12,end:14};//left 
	player.frameR={start:24,end:26};//right
	player.frameU={start:0,end:0};//up
	player.frameD={start:0,end:0};//down
	player.frameT={start:0,end:0};//turn
	player.frameA={start:0,end:0};//action
	player.baseV=300;
	player.baseJump=500;
	player.generateAnims();
}


//--------------------------------------MODULE: CREATE SCENE 1---------------------------------------------
class Scene1 extends BaseScene{
	constructor(key='scene1'){
		super(key);
		this.player;
		this.plate
	}
	preload(){

		this.load.image('ground','./assets/tanah_tengah.png');// for testing
		this.load.image('sky','./assets/sky.jpg');// for testing
		this.load.spritesheet('chibi','./assets/chibis.png',{frameWidth:48,frameHeight:48});// for testing
	}
	create(){
		//add sky background                               
		this.add.image(w/2,h/2,'sky');        
		//add player                                        
		this.player=makePlayer(this,150,50,'chibi');        //   THE
                                                            //   IsParent ERROR
                                                            //	 SEEMS TO 
		//add plateforms                                    //   HAPPENS
		this.plate=this.physics.add.staticGroup();          //   ARROUND
		for(let i=0;i<800;i+=128){                          //   HERE
			this.plate.create(0+i,h-50,'ground');			//	
		}                                                   //
		//add collider                                      //
		this.physics.add.collider(this.player,this.plate);  //   
	}

	update(){

		// to be filled	

	}
};

//---------------------------------MODULE: CONFIG OBJECT-----------------------------------------------------

let setConfigScene=function(s){
	this.scene=s;
}

const config={
	type:Phaser.AUTO,
	width:w,
	height:h,
	scenes:null,
	physics:{
		default: 'arcade',
		arcade: {
			gravity:{y:1000},
			debug:true
		}
	},
	setScene:setConfigScene
};

//----------------------------------MODULE: ENTRY POINT-----------------------------------------------------
/*
	THIS IS THE ENTRY POINT OF THE GAME
	This creates an instance of Phaser.Game class,
	using provided config object
	and scene files
*/

let scene1=new Scene1(config);
config.setScene(scene1);//set the first scene

const game=new Phaser.Game(config);

Any help is greatly appreciated.
PS: i run it on xampp

makePlayer() returns undefined, assigned to this.player.

1 Like

Oh silly me, i forgot to return the object itself. Thank you very much for your help :).