DisplayingSheets

Some sample code for displaying a simple sheet with OK/Cancel buttons on it:

- (void)runSheet
{
    int modalVal;

    [NSApp beginSheet:theSheet 
            modalForWindow:self
            modalDelegate:self 
            didEndSelector:NULL 
            contextInfo:NULL];

    modalVal = [NSApp runModalForWindow:theSheet];

    [NSApp endSheet:theSheet];
    [theSheet orderOut:nil];	
}

- (IBAction)acceptSheet:(id)sender
{
    [NSApp stopModalWithCode:1];
}

- (IBAction)cancelSheet:(id)sender
{
    [NSApp stopModalWithCode:0];
}

theSheet is an outlet connected to the sheet, which is an NSPanel in InterfaceBuilder.

-acceptSheet and -cancelSheet are actions that can be connected, for example, to OK/Cancel buttons on the sheet using InterfaceBuilder.

Upon return from runModalForWindow, the variable modalVal will contain either 0 or 1, depending on whether the sheet was canceled or accepted, respectively.

From: Seth Willits

Since sheets that are modal for the entire application are big no-no's, use this method which presents the sheet modal only to the window it is attached to.

- (IBAction)openSheet:(id)sender
{
	[NSApp beginSheet: theSheet
			modalForWindow: theParent
			modalDelegate: self
			didEndSelector: @selector(sheetDidEnd: returnCode: contextInfo:)
			contextInfo:NULL];
}

- (IBAction)theSheetOK:(id)sender
{
	[NSApp endSheet:theSheet returnCode: NSOKButton];
	[theSheet orderOut:nil];
}

- (IBAction)theSheetCancel:(id)sender
{
	[NSApp endSheet:theSheet returnCode: NSCancelButton];
	[theSheet orderOut:nil];
}

- (void)sheetDidEnd:(NSWindow *)sheet returnCode:(int)returnCode contextInfo:(void *)contextInfo
{
	if (returnCode == NSOKButton)
		NSBeep();
}

From: Alex Karahalios <Alex at Karahalios dot org>

Subject: Re: Use of NSSavePanel (or Open)

@interface ModalSavePanel : NSSavePanel
- (int)runModalForDirectory:(NSString *)path file:(NSString *)name
		   relativeToWindow:(NSWindow*)window;
@end

@implementation ModalSavePanel
- (int)runModalForDirectory:(NSString *)path file:(NSString *)name
		   relativeToWindow:(NSWindow*)window;
{
     int result;
     [super beginSheetForDirectory: path
                              file: name
                    modalForWindow: window
                     modalDelegate: self
                    didEndSelector: NULL
                       contextInfo:NULL];
     result = [NSApp runModalForWindow:self];
     [NSApp endSheet:self];
     return result;
}@end

From: The DJ <hartman at mac dot com>

Subject: Use of a sheet (Java solution)

Just for the record of the mailinglist, in Cocoa/Java the use of a sheet is as followed:

    public void openMenu(NSMenuItem sender) {
        op = new NSOpenPanel();
        op.setAllowsMultipleSelection(false);
        op.setCanChooseDirectories(false);
        op.setCanChooseFiles(true);
        op.beginSheetForDirectory(directory,
            filename,null,window,this,
            new NSSelector("done",new Class[] {
                NSOpenPanel.class, int.class}),
            null);
    }
    
    public void done(NSOpenPanel sheet, int returnCode){
            if (returnCode == NSAlertPanel.DefaultReturn) {
                open_file = sheet.filename();
                System.out.println(open_file);
            }
    }

From: MattRidley

Subject: simpler way to get an OK/Cancel sheet, without using Interface Builder

You can just use the NSBeginAlertSheet?() function, documented in the Functions section of the AppKit documentation.

- (void)runAlertSheet
{
	NSBeginAlertSheet(@"You must be insane!", @"OK", @"Cancel",
		nil, myWindow, self, NULL,
		@selector(endAlertSheet:returnCode:contextInfo:),
		NULL,
		@"Are you sure you want to do such a reckless thing?");
}

- (void)endAlertSheet:(NSWindow *)sheet returnCode:(int)returnCode contextInfo:(void *)contextInfo
{
	if (returnCode == NSAlertDefaultReturn) {
		NSLog(@"Clicked OK");
	}
	else if (returnCode == NSAlertAlternateReturn) {
		NSLog(@"Clicked Cancel");
	}
}

Note that myWindow is an outlet connected to the window you want the alert sheet to display over (roll out from).

You should never use modal sheets...whats the use?

-- chmod007@mac.com

When should I display my sheet so that it runs after startup of the app? Right? now I have it in (void)windowDidBecomeKey: and have it set up to only run the shhet once (using a boolean to see if it has run before), but the sheet still isn't in focus. I need to click on the text field.

how about applicationDidFinishLaunching or windowControllerDidLoadNib

-- SamGoldman

- (void)awakeFromNib {/* Foo */};

From: Steve Christensen <punster=at=mac=dot=com> Subject: Re: Use of NSSavePanel (or Open)

I tried Alex Karahalios' code above and found that it didn't didn't clean up correctly. Here's my version, done as a category on NSSavePanel:

@interface NSSavePanel(ModalSheets)

- (int)runModalForDirectory:(NSString*)path file:(NSString*)name
            types:(NSArray*)fileTypes relativeToWindow:(NSWindow*)window;

- (void)modalSavePanelDidEnd:(NSOpenPanel*)panel returnCode:(int)returnCode
            contextInfo:(void*)contextInfo;

@end

@implementation NSSavePanel(ModalSheets)

- (int)runModalForDirectory:(NSString*)path file:(NSString*)name
            types:(NSArray*)fileTypes relativeToWindow:(NSWindow*)window
{
    int result;

    [super beginSheetForDirectory:path file:name modalForWindow:window
            modalDelegate:self
            didEndSelector:@selector(modalSavePanelDidEnd:returnCode:contextInfo:)
            contextInfo:nil];

    result = [NSApp runModalForWindow:self];

    [NSApp endSheet:self];

    return result;
}

- (void)modalSavePanelDidEnd:(NSOpenPanel*)panel returnCode:(int)returnCode
            contextInfo:(void*)contextInfo
{
    [NSApp stopModalWithCode:returnCode];
}

@end