Question

This problem seems very simple to me, but I’ve been unable to fix it, or find an answer anywhere.

This is in a class constructor for a class called block, block_maker is the object that called the constructor, an instance of level.

this.bitmap = new Bitmap(this.bitmap_data);

this.addChild(this.bitmap);     

this.block_maker.stage_foreground.addChild(this);

In level, stage_foreground is added to the stage, but nothing appears. trace(stage_foreground.numChildren); shows the correct count of children, and var temp = (this.stage_foreground.getChildAt(0)); trace(temp.numChildren); correctly but the children OF the children don’t actually show up, the stage just stays blank.

When I change the above code to

this.bitmap = new Bitmap(this.bitmap_data);

this.block_maker.stage_foreground.addChild(this.bitmap);

the blocks appear on the stage, as children of level_instance.stage_foreground, but with this method, the bitmaps aren’t appropriately positioned, as they have no position data. I can simply give this.bitmap x and y positions, and it works, but I am curious as to why it won’t work when just adding the bitmap as a child to the block and then adding that as a child to stage_foreground.

I’ve tried replacing this.bitmap with a number of other object classes, such as a temporary MovieClip I made, or a Shape, but nothing shows up, so I know it has nothing to do with it being a Bitmap.

Answer 1

As you stated

This is in a class constructor for a class called block, block_maker
is the object that called the constructor, an instance of level.

this.bitmap = new Bitmap(this.bitmap_data);
this.addChild(this.bitmap);     
this.block_maker.stage_foreground.addChild(this);

The level class needs to to extend a display object for it to show up.
In other words

"this"

has to be a display object or extend it in some form.

The reason this doesn’t work.

this.block_maker.stage_foreground.addChild(this);

and this does

this.block_maker.stage_foreground.addChild(this.bitmap);

Is because "this" is not a display object but "this.bitmap" is.

The DisplayObject class is the base class for all objects that can be placed on the display list.