When this style is set, native decorations like frame and title bar are not shown.

This style is suggested when using LAFs that provide their own frame and title bar. Without the Undecorated style, these LAFs show a double title-bar.

Another scenario where this style is useful is the WebClient environment. In the WebClient environment you might want to remove the decoration of the window so the program screen will look like a common HTML form.

This style has no effect on Docking and MDI windows.

Notification windows are always undecorated by default.

 

Example - Display a window with undecorated style