This class is currently used by the utility method, mobileViewer.displayPopup() to display a closeable panel at the bottom of the screen. It contains a title bar, close button, and a scrollable main area to which custom content may be added.
The parent div element that should contain the panel. Note that the panel will show/hide itself by setting the visibility of this div, so it is good practice to create a div specifically to contain the panel.
A callback method to invoke when the panel is closed. This is useful if you wish to deactivate a control when the user closes the panel it's using to display information