Delegates or Properties, take your pick. PROPERTIES Class A (ViewController) wants to communicate with Class B (ViewController) Before calling Class B, do the following: In Class B, create a @property NSString* receivedValue; In Class A, #import Class B then in the method that calls B (either prepareForSegue or didSelectRowAtIndexPath or some method where you present Class B view controller, do the following: Class B *calledVC = alloc/init calledVC.receivedValue = ‘whatever value you want to pass’; then call Class B VC Done! DELEGATES Let’s say Class B wants to notify Class A that something has finished. In Class B add this above your @interface: @protocol YourDelegateProtocol <NSObject> – (void)itemWillBePassed; @end… Read More
Continue ReadingUsing NSUserDefaults
This is handy when saving credentials to a device so the user doesn’t have to re-login every time he launches the app. NOTE: This is not useful for saving large amounts of data or data that will change frequently. Use iCloud or persistent state stores such as databases or xml or plist files for that! Once you have the data you wish to save somewhere in your app, call the following: // call the store object NSUserDefaults *prefs = [NSUserDefaults standardUserDefaults]; // set an object for it [prefs setObject:imageView.image forKey:@”keyToLookupImage”]; // call sync to save it [prefs synchronize]; then later in the beginning or launch of an app you can… Read More
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