Creating a Modal Dialog or Window in Cocoa Objective-C?

There are several ways to do this — and in fact two different kinds of modal dialog in OS X: application-modal and window-modal. Using the wrong one will annoy people. One is a sheet, which is attached to the window that it affects (save dialogs are an example of this). The other is application-modal, which blocks the whole application (open dialogs work this way, since they don't apply to any window that exists yet). Apple's sheet documentation should help get you oriented.

Thank you...

(Example). Create a nib with name "About"

if(pAbtCtrl == nil)
        pAbtCtrl = [[AboutWindowController alloc] initWithWindowNibName:@"About"];

pAbtWindow = [pAbtCtrl window];

[NSApp runModalForWindow: pAbtWindow];

[NSApp endSheet: pAbtWindow];

[pAbtWindow orderOut: self];