removeChild doesn't work in canvas

[francescot]

Hello I've been trying to adapt the following code with out success, can someone tell me where I'm going wrong? Need one button to add and another to remove:

var that = this;
this.buttonAdd.addEventListener("click", addFromLibrary);
this.buttonRemove.addEventListener("click", removeClip);

function addFromLibrary(e)
{	
	that.addChild(new lib.Rectangle());
}
function removeClip(e){
    this.stage.removeChild(myRectangle);
}

 Thanks 

[JoãoCésar]

Hi.

You should store the newly created instance in a variable. Also, if you're adding the instance to the main timeline then you should remove it from there and not from the stage. And the this keyword inside of a event handler function won't refer to the main timeline by default.

This should work:

var that = this;
var myRectangle;

function addFromLibrary(e)
{
	if (!myRectangle)
	{
		myRectangle = new lib.Rectangle();
		that.addChild(myRectangle);
	}
}

function removeClip(e)
{
	if (myRectangle)
	{
		that.removeChild(myRectangle);
		myRectangle = null;
	}		
}

this.buttonAdd.addEventListener("click", addFromLibrary);
this.buttonRemove.addEventListener("click", removeClip);

I hope it helps.

Regards,

JC

[francescot]

Great thanks for your quick reply.

I'll try it out

[francescot]

Thanks for this it's working nicely.

However I'm trying to place it on the canvas on at particular co-ordinates, while it adds the movie clip it won't remove it:

var that = this;
function addFromLibrary(e)
{ 
    var rec = new lib.Rectangle();
    rec.x = 250;
    rec.y = 150;
    that.addChild(rec);
}
function removeClip(e)
{
	if (rec)
	{
		that.removeChild(rec);
		rec = null;
	}	
}

this.buttonAdd.addEventListener("click", addFromLibrary);
this.buttonRemove.addEventListener("click", removeClip);

[JoãoCésar · Accepted solution]

Hi.

Nice to know that it worked.

Your code is not working because you're declaring the rec variable inside of the addFromLibrary function. In this way, the rec var is only available inside of that function.

Just declare the rec variable in the root level/scope. Like this:

var that = this;
var rec;

function addFromLibrary(e)
{ 
    rec = new lib.Rectangle();
    rec.x = 250;
    rec.y = 150;
    that.addChild(rec);
}

function removeClip(e)
{
	if (rec)
	{
		that.removeChild(rec);
		rec = null;
	}	
}

this.buttonAdd.addEventListener("click", addFromLibrary);
this.buttonRemove.addEventListener("click", removeClip);

[francescot]

Many thanks

I never noticed that of course I had the variable in the add function.

One thing I've just noticed it that if the addbutton is press more than once the removeButton stops functioning.

Is there a way that this can be eliminated as both functions would need to be used inumerable times.

Thanks again

[francescot · Accepted solution]

Hello

Just had another go with it and gone back to thr original, just added the x and y to addChild and that works well

var that = this;
var myRectangle;

function addFromLibrary(e)
{
	if (!myRectangle)
	{
		myRectangle = new lib.Rectangle();
		myRectangle.x = 250;
		myRectangle.y = 150;
		that.addChild(myRectangle);
	}
}

function removeClip(e)
{
	if (myRectangle)
	{
		that.removeChild(myRectangle);
		myRectangle = null;
	}		
}

this.buttonAdd.addEventListener("click", addFromLibrary);
this.buttonRemove.addEventListener("click", removeClip);

Thanks for your help on this, much appreciated.