The WindowControlsOverlayGeometryChangeEvent interface of the Window Controls Overlay API is passed to geometrychange when the size or visibility of a desktop Progress Web App's title bar region changes.

WindowControlsOverlayGeometryChangeEvent() Experimental

Creates a WindowControlsOverlayGeometryChangeEvent event with the given parameters.

Also inherits properties from its parent Event.

WindowControlsOverlayGeometryChangeEvent.titlebarAreaRect Read only Experimental

A DOMRect representing the position and size of the title bar region.

WindowControlsOverlayGeometryChangeEvent.visible Read only Experimental

A Boolean that indicates whether the window controls overlay is visible or not.

The following example shows how to use a WindowControlsOverlayGeometryChangeEvent instance by adding an event handler on the Navigator.windowControlsOverlay property, to listen to geometry changes of a PWA's title bar region.

if ("windowControlsOverlay" in navigator) {
  navigator.windowControlsOverlay.addEventListener(
    "geometrychange",
    (event) => {
      if (event.visible) {
        const rect = event.titlebarAreaRect;
        // Do something with the coordinates of the title bar area.
      }
    },
  );
}

• The Window Controls Overlay API.