3.3 Creating Windows

If you use Xlib to create your own top-level windows (direct children of the root window), you must observe the following rules so that all applications interact reasonably across the different styles of window management:

• You must never fight with the window manager for the size or placement of your top-level window.

• You must be able to deal with whatever size window you get, even if this means that your application just prints a message like ``Please make me bigger'' in its window.

• You should only attempt to resize or move top-level windows in direct response to a user request. If a request to change the size of a top-level window fails, you must be prepared to live with what you get. You are free to resize or move the children of top-level windows as necessary. (Toolkits often have facilities for automatic relayout.)

• If you do not use a toolkit that automatically sets standard window properties, you should set these properties for top-level windows before mapping them.

For further information, see "Inter-Client Communication Functions" and the Inter-Client Communication Conventions Manual.

XCreateWindow() is the more general function that allows you to set specific window attributes when you create a window. XCreateSimpleWindow() creates a window that inherits its attributes from its parent window.

The X server acts as if InputOnly windows do not exist for the purposes of graphics requests, exposure processing, and VisibilityNotify events. An InputOnly window cannot be used as a drawable (that is, as a source or destination for graphics requests). InputOnly and InputOutput windows act identically in other respects (properties, grabs, input control, and so on). Extension packages can define other classes of windows.

To create an unmapped window and set its window attributes, use XCreateWindow().

To create an unmapped InputOutput subwindow of a given parent window, use XCreateSimpleWindow().

Next: Destroying Windows