Extending TabLayoutPanel in GWT
===

I'd like to create my custom TabLayoutPanel class. Here's its code:

    public class ResizableTabLayoutPanel extends TabLayoutPanel {
	private boolean drag_drop = false;
	private boolean allowX;
	private boolean allowY;

	public ResizableTabLayoutPanel(double barHeight, Unit barUnit) {
		super(barHeight, barUnit);
	}
    //...
    }

And here is the class I want to use it in:
    
    public class LeftPanel extends Composite implements RequiresResize {

	private static LeftPanelUiBinder uiBinder = GWT
		.create(LeftPanelUiBinder.class);
	@UiField ResizableTabLayoutPanel tP;
	
	interface LeftPanelUiBinder extends UiBinder<Widget, LeftPanel> {
	}
    //...
    }

Here's my ui.xml code:

    <p2:ResizableTabLayoutPanel barHeight="18" barUnit="PX" height="150px" ui:field="tP">
        <p2:tab>
            <p2:header>x_Publ</p2:header>
            <p2:SearchTree ui:field="qtPub"/>
        </p2:tab>
	<p2:tab>
	    <p2:header>x_Pers</p2:header>
            <p2:SearchTree ui:field="qtPers"/>
        </p2:tab>
    </p2:ResizableTabLayoutPanel>

Now, I keep getting this error from uibinder:
    
    [ERROR] [dms] - Line 42: Type mismatch: cannot convert from TabLayoutPanel to ResizableTabLayoutPanel

Simply I'm doing something wrong, but I can't see what.