Custom Sheets don’t need their own xib files

When you want to use custom sheets, Apple’s Documentation suggests that you create another xib file for the sheets(Using Custom Sheets).

But in fact, you don’t have to use a separate xib.

1. Create a controller class which handles both parent window and sheet window.

SheetTestController.h

@interface SheetTestController : NSObject {
	IBOutlet NSWindow *mainWindow;  //paent window
	IBOutlet NSWindow *sheetWindow; //sheet window
}

- (IBAction)showSheet:(id)sender; // open sheet on parent window
- (IBAction)closeSheet:(id)sender;// close sheet

@end

SheetController.m

@implementation SheetTestController

- (IBAction)showSheet:(id)sender
{
	[NSApp beginSheet: sheetWindow
	   modalForWindow: mainWindow
		modalDelegate: self
	   didEndSelector: @selector(didEndSheet:returnCode:contextInfo:)
		  contextInfo: nil];
}

- (IBAction)closeSheet:(id)sender
{
    [NSApp endSheet:sheetWindow];
}

- (void)didEndSheet:(NSWindow *)sheet returnCode:(int)returnCode contextInfo:(void *)contextInfo
{
    [sheet orderOut:self];
}

@end

2. Add “Show Sheet” button to parent window.



3. Add a sheet window, and put “close sheet” button on the window.


make sure that “Visible At Launch” is unchecked.


4. Add a SheetTestController object to the xib.



5. Connection settings of SheetTestController should be like this.

This is a little easier than “separate xib” way, but has disadvantages noted below.

• increses memory usage because the sheet window always takes up some memory instead of instanciated only when necessary.
• It’s difficult to use the sheet window from other xib files.