View Full Version : Problems switching views iOS & xcode

Aug 26, 2012, 10:13 PM
Hi guys,

I am having troubles with transitioning between two views.
I have created a button to call switchViews. But, when I press the button the view turns white.

The view(s) creation is as follows;

// Create main window and root view controller
self.mainWindow=[[UIWindow alloc]initWithFrame:[[UIScreen mainScreen]bounds]];
self.mainWindow.backgroundColor=[UIColor whiteColor];
self.rootViewController=[[ViewController alloc] init];
[self.mainWindow makeKeyAndVisible];

// Create child view controllers
self.firstViewController=[[ViewController alloc] init];
[self.rootViewController addChildViewController:self.firstViewController];

self.secondViewController=[[ViewController alloc] init];
[self.rootViewController addChildViewController:self.secondViewController];

// Get screen boundaries
CGRect screenBound = [[UIScreen mainScreen] bounds];
CGSize screenSize = screenBound.size;
CGRect bounds=self.mainWindow.bounds;

// Create view1 and assign to firstViewController
view1=[[UIView alloc]initWithFrame: bounds];
[view1 setBackgroundColor:[UIColor yellowColor]];
[self.mainWindow addSubview:view1];

// Create view2 and assign to secondViewController
view2=[[UIView alloc]initWithFrame: bounds];//CGRectMake(100,100,100,100)];
[view2 setBackgroundColor:[UIColor redColor]];

// Button to switch from view1 to view2
UIButton* OurButton=[UIButton buttonWithType:UIButtonTypeRoundedRect];
[OurButton setTitle:@"Switch to 'View 2'" forState:UIControlStateNormal];
[OurButton setTitleShadowColor:[UIColor colorWithRed:1.0f green:0.0f blue:0.0f alpha:1.0f] forState:UIControlStateNormal];
[OurButton setTitleColor:[UIColor colorWithRed:0.0f green:0.0f blue:0.0f alpha:1.0f] forState:UIControlStateNormal];
[OurButton setFrame:CGRectMake(22,screenSize.height-(44*2),screenSize.width-44,44)];
[view1 addSubview:OurButton];
[OurButton addTarget:self action:@selector(switchViews) forControlEvents:UIControlEventTouchUpInside];

And to switch the views I have the following;

- (void)switchViews
[UIView beginAnimations:@"View Flip" context:nil];
[UIView setAnimationDuration:1.25];
[UIView setAnimationCurve:UIViewAnimationCurveEaseInOut];

UIViewController *coming=nil;
UIViewController *going=nil;
UIViewAnimationTransition transition;

transition = UIViewAnimationTransitionFlipFromRight;

[UIView setAnimationTransition: transition forView:view1 cache:YES];
[coming viewWillAppear:YES];
[going viewWillDisappear:YES];
[going.view removeFromSuperview];
[view1 insertSubview: coming.view atIndex:0];
[going viewDidDisappear:YES];
[coming viewDidAppear:YES];

[UIView commitAnimations];
Any help would be awesome as I am an iOS / XCode / Mac newbie, with solid programming experience under Windows & C++.

Trying to come to the light side!

Aug 27, 2012, 05:46 AM
Why use code at all? Is there any particular reason you're not using storyboard and segues? Ray Wenderlich has a very nice tutorial on storyboards - I suggest looking at it here:

If you want a standard looking/behaving iOS app, use storyboards. If you want it heavily customized... IDK what to do... I do my games mostly in code, but I don't know if other people have a better way of using Xcode's built in graphical design tools.

Aug 27, 2012, 09:04 AM
Lonewolff, a few things:

- Where does the code from your first snippet reside? It means less when it lacks the context of where it is run.

- Assuming it is in your appDelegate's application:didFinishLaunchingWithOptions:, it is not usual to put the button handler code in your appDelegate as well. switchViews should be a part your viewController's code.

- OurButton does not follow standard naming conventions. It looks like a class name, when in fact it represents a class instance. ourButton would follow the standard, in this case.

- Have you looked at using UIViewController's presentViewController:animated:completion: method? It would reduce the amount of code in your switchViews method.

- What resources are you using to educate yourself about the fundamentals of Objective-C / iOS development?


P.S. How and where are view1 and view2 defined?