There are multiple window types in the Screen API.
Each window type has a different use and different positioning rules,
and each window is typically used to display different
types of content.
You specify the window type at window creation time. The following types are available.
- SCREEN_APPLICATION_WINDOW
- The window type that's used to display the main application.
The X and Y coordinates are always relative to the dimensions
of the display.
Application windows can be used to display an application
in fullscreen mode:

- SCREEN_CHILD_WINDOW
- The subwindow type that's commonly used to display a dialog. You
must add a child window to an application's window group;
otherwise, the child window is invisible. A child window's
display properties are relative to the application window to
which it belongs. For example, the X and Y coordinates of the
child window are all relative to the top-left corner of the
application window.
Child windows can be used to display minimized applications:
- SCREEN_EMBEDDED_WINDOW
-
Used to embed a window control within an object. Like the
child window, the X and Y coordinates of the embedded window
are all relative to the top-left corner of the application
window. You must add an embedded window to an application's
window group, otherwise the embedded window is invisible.