Illustrator Scripting :: Create A Palette With Some Buttons

I am writing a script for Illustrator. I created a palette with some buttons. I like to keep the palette open while working in Illustrator. The problem is, that the buttons don't work. For example, I have a delete button that should delete my active selection. When I change the Window Type from palette to dialog everything works correctly.

var w = new Window ("palette");
w.orientation = "row";
w.text = "Path Transform";
var f = File ("/C/icons/corner-tr.png");
var corner_tr = w.add ("iconbutton", undefined, f );
var corner_tl = w.add ("iconbutton", undefined, f );
var corner_br = w.add ("iconbutton", undefined, f );
var corner_bl = w.add ("iconbutton", undefined, f );
 corner_tr.onClick = function () {
    selectedObject[0].remove();
    createLines();
}