macOS template for NSDocument

[MrFusion]

Hi everyone

I am trying to implement a template / stationary system via a subclass of NSDocumentController. Not much can be found about this topic via google, unfortunately. I tried the following, but each approach brings its own problem. Maybe you have a solution?

#pragma mark -
#pragma mark templates
-(id) openUntitledDocumentFromTemplate:(NSURL *) url 
							  	 error:(NSError **) outError
{
	/**
	 Create a new document from a template.
	 Calls makeUntitledDocumentOfType and revert to previous saved document a.k.a. template
	 Calls defaultTemplate when template is nil.
	 */
	id newDoc = nil;
	
	if (!url)
		url = [self defaultTemplate];
	NSString *templateDocumentType = [self typeForContentsOfURL:url
														  error:outError];
	if (*outError != NULL) 
		return nil;
	
	@try {
#if 0
		
		newDoc = [[NSDocumentController sharedDocumentController] reopenDocumentForURL:nil
																	 withContentsOfURL:url
																				 error:outError]; //deletes original
		
		if (*outError != NULL)  @throw [NSException exceptionWithName:@"MyDocumentController" 
															   reason:@"Can not load data from template" 
															 userInfo:nil];		
#endif
		
#if 0
		newDoc = [[NSDocumentController sharedDocumentController] makeDocumentForURL:nil
																   withContentsOfURL:url
																			  ofType:templateDocumentType
																			   error:outError];
		[newDoc makeWindowControllers];
		[newDoc showWindows]; //window disappears immediately
		
		if (*outError != NULL)  @throw [NSException exceptionWithName:@"MyDocumentController" 
															   reason:@"Untitled document can not be created." 
															 userInfo:nil];
#endif
		
#if 1
		newDoc = [[NSDocumentController sharedDocumentController] makeUntitledDocumentOfType:templateDocumentType
																					   error:outError];
		if (*outError != NULL)  @throw [NSException exceptionWithName:@"MyDocumentController" 
															   reason:@"Untitled document can not be created." 
															 userInfo:nil];
		
		[newDoc revertToContentsOfURL:url 
							   ofType:templateDocumentType 
								error:outError]; //this automatically displays the window
		
		
		if (*outError != NULL)  @throw [NSException exceptionWithName:@"MyDocumentController" 
															   reason:@"Can not load data from template" 
															 userInfo:nil];
		[[newDoc undoManager] disableUndoRegistration];
		[newDoc setFileURL:nil];

		[[newDoc undoManager] removeAllActions]; //still possible to do undo/ctrl-z one more time. Should be zero in the ideal solution
	// [[newDoc undoManager] enableUndoRegistration]; //removeAllActions reenables undomanager, so this line is unnecessary. If uncommented, the document will appear only briefly

#endif		
	}
	@catch (NSException * exception) 
	{
		[self removeDocument:newDoc];
		newDoc = nil;
	}
	
	return newDoc;
}

 

[Sydde]

What I would probably do is put an ivar in your NSDocumentController for the template file url (which is the url that is being passed in in this method). Then just send a

[super openUntitledDocumentAndDisplay:YES error:&errorVariable];

Then you design your document class so that its -initWithType:error: method will ask the document controller for template data, which your document controller will read from its template url (after which, the url will be released and set to nil) or from the default template if the stored template url is nil.