mouse-over detection not working for repsonsive window layout

[jango-fx]

if i make the window resizable and change the position of my controls relative to the new window size, they stop working (as long, as the window size differs from startup).

import controlP5.*;

int windowWidth, windowHeight;

ControlP5 cp5;
Toggle toggle;

void setup()
{
  surface.setResizable(true);
  registerMethod("pre", this);

  cp5 = new ControlP5(this);
  toggle = cp5.addToggle("check");
}

void pre() {
  if (windowWidth != width || windowHeight != height) {
    windowWidth = width;
    windowHeight = height;
    toggle.setPosition(width/2-20, height/2-10);
  }
}

void draw()
{
}