iOS Archives

Assuming you’re using an app template that includes Core Data, you will have access to the Managed Object Context. In the simplest form, and without custom Entity classes setup, you can use key/value coding to set your object’s properties. In fact, the Master/Detail template does this. Here’s an example for an Entity named Event with […]

Likewise we can save our previously selected file using an NSSavePanel. It too is easy to use, just as the NSOpenPanel. For a save action to make sense we need to have some data to save, so in this example we will copy an existing file (self.myURL) to the new URL that the save panel […]

NSOpenPanel is surprisingly easy to use: create the panel, call the openPanel method, and handle the returned URL object in a block. In this example we invoke the panel from a button in the main window, then display the returned URL in a textLabel: – (IBAction)loadFile:(id)sender { // create an open documet panel NSOpenPanel *panel […]

Likewise, here’s how we return the number of rows using a fetched results controller – as provided by the Master / Detail template: – (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section { id <NSFetchedResultsSectionInfo> sectionInfo = [[self.fetchedResultsController sections]objectAtIndex:section]; return [sectionInfo numberOfObjects]; }

I can never remember how to do this. Here’s the method provided by the Master / Detail template when using Core Data: – (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView { return [[self.fetchedResultsController sections] count]; }