Question

I droped into a behaviour which i didnt expect, please explain me to understand and fix it.
– The issue is as follow : I have a class which holds a label, and this class is used inside a itemRenderer as , the whole thing work withotu exception, but it doest not show the text of the label.
I have tried with adding a Button but the issue remains – it never actually add an the button.

Why?

public class BusTreeNode extends UIComponent
{
    protected var label : Label;

    public function BusTreeNode()
    {
        super();

        label = new Label();
        this.addChild( label );
        label.x    = 40;
        label.y    = 2; 
        label.text = "test";
    }
}

… Inside itemRenderer :

<sl:BusTreeNode width="100%" />

Answer 1

I suppose the problem is you haven’t measure() implementation in your BusTreeNode class. So your component has 0x0 size by default. This declaration:

<sl:BusTreeNode width="100%" />

still give 0 as height.

You can read more about Flex components measuring here. And this article is very useful for creating custom components.