How to add an animation to the UIView in viewDidAppear? - iphone

I tried to add a animation to viewDidLoad and viewDidAppear, but it doesn't work:
- (void)viewDidAppear:(BOOL)animated{
[UIView beginAnimations:#"transition" context:NULL];
[UIView setAnimationTransition:110 forView:self.view cache:YES];
[UIView commitAnimations];
}
Why?

I had the same problem and I think I found the solution on this SO question.
When viewDidAppear gets called you still don't see anything on the screen (despite the name), but you are about to. You can then use a performSelector:withDelay or an NSTimer to launch your animation. The delay can just be 0.1 and your animation will play just when the screen appears.
- (void)viewDidAppear:(BOOL)animated {
[super viewDidAppear:animated];
NSLog(#"View did appear!");
[self performSelector:#selector(animationCode) withObject:nil afterDelay:0.1f];
}
- (void)animationCode {
// you animation code
}

You are not telling the view which state it should animate to so it won't do anything. You need to place code between beginAnimations:context: and commitAnimations that changes the appearance of the view (e.g. by removing one subview and adding another).

You're not using beginAnimations: and commitAnimations correctly. You're supposed to put something in between them that normally wouldn't be animated: e.g. with self.view.alpha = 0.5 you get a fading effect. They have no effect on anything that isn't between them.
By the time viewDidAppear: is called, your view, well... has appeared. It's too late to animate anything. What you actually want to do is something like this:
- (void)showMyViewWithAnimation {
[UIView beginAnimations:nil context:nil];
[UIView setAnimationTransition:110 forView:childView cache:YES];
[parentView addSubview:childView];
[UIView commitAnimations];
}
In the example above, childView is what in your example is called self.view.
Please write out the name of the transition; no one knows what 110 is by looking at it. It's bad style. </pedantry>

Related

Switch Views (with Animation) why does my screen become white when I use removeFromSuperView?

I've just started objective C and I'm enhancing a current iPhone app. Previous codes were done by someone else. I'm trying to switch views back - and add a page curl animation in, but when I try to go back (removefromsuperview) my screen just goes white. I understand that I'm referring to the wrong view but I have no idea how to refer it to the right one.
-(IBAction)switchBack{
[UIView beginAnimations:#"flipview" context:nil];
[UIView setAnimationDuration:1];
[UIView setAnimationCurve:UIViewAnimationCurveEaseInOut];
[UIView setAnimationTransition:UIViewAnimationTransitionCurlUp forView: self.view.superview cache:YES];
//[self.navigationController popToRootViewControllerAnimated:YES];
[self.view removeFromSuperview];
[UIView commitAnimations];
}
The commented out popToRootViewController allows me to go back to the previous page. Any help would be really appreciated. I'm going crazy with all this views >< Thanks!
Try something like this:
[UIView transitionWithView:self.navigationController.view duration:1.0 options:UIViewAnimationOptionTransitionCurlDown
animations:^{
[self.navigationController popToRootViewControllerAnimated:NO];
}
completion:NULL];
that happened because you're trying to remove the view from its superview, which is not the way it is added before, don't use removeFromSuperView if you didn't use addSubview when showing the view it self.
you should add this code to the parent which calls your current view
viewNotLoggedHome.modalTransitionStyle =
UIModalTransitionStylePartialCurl;
this way you've stated a "partial curl" transition animation for the view u're pushing
and just delete all your animation block on switchBack function so it only consist of
-(IBAction)switchBack
{
[self.navigationController popToRootViewControllerAnimated:YES];
}
Instead of usign self.view which is a reference to your superview, you need to use the name of the view you want to use.
f.e. :
- If you have view1 and view2
- you can delete view1 by using
[view1 removeFromSuperview];

UITabBarController View Transition error

OKay I have been working on this problem for a while now, And It is well beyond my expertise thus why I am asking for help again.
I am trying to animate the transition for a tabbarbutton click to another view. I have declared in both viewController (ViewWillAppear) methods the code below
- (void)viewWillAppear:(BOOL)animated
{
//TODO: Fix transition animation
[UIView beginAnimations:nil context:NULL];
[UIView setAnimationDuration:1.0];
[UIView setAnimationTransition:UIViewAnimationTransitionFlipFromRight
forView:self.view cache:YES];
[UIView setAnimationCurve:UIViewAnimationCurveEaseOut];
[UIView commitAnimations];
[super viewWillAppear:animated];
}
FirstViewController to the right and SecondViewController to the left.
Now the problem is happening when the user loads the app for the first time, once everything loads up and the user clicks on the tabbarbutton to go to the second view, it dose not flip.. but when you go back to the FirstView it animates then if you go to the second again it will animate this time round.. Dose anyone have any idea why this is happeneing? if you do your help would be greatly appreciated!
UPDATE::
I am trying to add a animation into viewDidLoad, however there is already an animation for an opening sequence I am loading straight away.
[super viewDidLoad];
// Do any additional setup after loading the view, typically from a nib.
//-- Start Opening Animation ------->
CGRect vaultTopFrame = vaultTop.frame;
vaultTopFrame.origin.y = -vaultTopFrame.size.height;
CGRect vaultBottomFrame = vaultBottom.frame;
vaultBottomFrame.origin.y = self.view.bounds.size.height;
[UIView beginAnimations:nil context:nil];
[UIView setAnimationDuration:2.5];
[UIView setAnimationDelay:2.0];
[UIView setAnimationCurve:UIViewAnimationCurveEaseInOut];
vaultTop.frame = vaultTopFrame;
vaultBottom.frame = vaultBottomFrame;
[self.view bringSubviewToFront:vaultTop]; //this should place this subview above any others on the same page
[self.view bringSubviewToFront:vaultBottom]; //this should place this subview above any others on the same page
[UIView commitAnimations];
I think this might be messing things up for me what do you think?
You do not have animation when the app loads up. Set animation in viewDidLoad for animation when the view loads up and viewDidAppear will give you animations when the user makes transition after wards (every time the tab is clicked).
This may or may not be the problem, but you should call
[super viewWillAppear:animated];
at the beginning of the method, before your animation code.

UIView Animation Problem

[UIView beginAnimations:nil context:NULL];
[UIView setAnimationDuration:0.30f];
[UIView setAnimationTransition:UIViewAnimationTransitionNone forView:viewSettings cache:YES];
viewSettings.alpha = 0;
[viewSettings removeFromSuperview];
[UIView commitAnimations];
I ve written the code above that works well when I add the view via animation, but it doesn't work when i remove the view from superview. Animation works if I remove [viewSettings removeFromSuperview] line. I don't know where I'm doing wrong.
You need to remove it from the superview after the animation has completed. This is very easy to accomplish if you use the blocks based API, which Apple is encouraging you to do:
[UIView transitionWithView:viewSettings
duration:0.30f
options:UIViewAnimationOptionTransitionNone
animations:^{
[viewSettings setAlpha:0];
} completion:^(BOOL finished) {
[viewSettings removeFromSuperview];
}];
You can read about all the options in Apple's documentation.
removeFromSuperview is not an animatable action, so it is getting performed immediately. Once you commitAnimations, your view is no longer part of it's superview, so you can't see the animation, if it is still even happening.
If you want your animation to happen, then the view to get removed, call removeFromSuperview when the animation ends, such as in a selector specified with setAnimationDidStopSelector:.
Try removing view after the animation is completed. Initially alpha value of the view is 1 then, you apply the animation and make it 0. Now the view is still there but it is not visible. Once the animation is over then remove the view. I think it should work.
I think viewSettings is removed before you commit the animation.
Try inverting the two last lines.

How to properly release a view after a UIView Animation ? :)

I have a method like the following:
- (void)add:(id)sender {
MyAddViewController *controller = nil;
controller = [[MyAddViewController alloc] initWithAddType:1];
//controller.delegate = self;
// Do some animation. Slide it in from the right side of the screen.
CGPoint initialCenter = self.view.center;
controller.view.center =
CGPointMake(initialCenter.x + 320, initialCenter.y);
// Add the subview now with it's center + 320 off the screen.
[self.view addSubview:controller.view];
[UIView beginAnimations:#"animation" context:NULL];
[UIView setAnimationDuration:0.35];
[UIView setAnimationDelegate:self];
controller.view.center = CGPointMake(initialCenter.x, initialCenter.y);
//[UIView setAnimationDidStopSelector:#selector(aMethodToBeCalledAfterAnimationEnd:finished:context:)];
[UIView commitAnimations];
//[controller release];
}
You see I have a controller release as the last line in my add method. If I uncomment this line the animation completely dies and it just dumps the view into place with no animation.
Is there a better way to do release without having to create another method which does cleanup via [UIView setAnimationDidStopSelect:#selector(aMethodToBeCalledAfterAnmiationEnd... ?
Or can I do something like setAnimationDidStopSelector:#selector([controller release]) ? :)
Thanks in advance!
Using setAnimationDidStopSelector: is the proper way to solve the generic problem of releasing resources after an animation completes.
Take a step back and reconsider what you're doing here, though. Why are you looking to free the controller you just created? If you are only creating the controller for the purpose of getting at the view, that isn't the right way to do it. Build yourself a factory method to create your view, or use the methods in NSBundle to load the view from a NIB.
You can do this:
[UIView setAnimationDelegate: controller];
[UIView setAnimationDidStopSelector:#selector(release)];
I see you tagged this iphone-sdk-4.0. You could use the new block-based animations to do this and any other cleanup. See the documentation for details.

Wait before execute istruction

I wan't to perform an animation before quitting a view. The problem is that if I write this code:
[self animationMethod];
[self removeFromSuperview];
the animation is not presented because the removeFromSuperview instruction is immediatly executed, i suppose.
There's a way to specify thath the removeFromSuperview method must be executed after a a specified time? thanks.
Does animationMethod use a [UIView beginAnimations: context:] section? If that's the case, you should use the animation delegate. Specifically:
[UIView beginAnimations:nil context:nil];
[UIView setAnimationDelegate:self];
[UIView setAnimationDidStopSelector:#selector(removeFromSuperview)];
//Your animation stuff
[UIView commitAnimations];
Otherwise, if you're doing something else that doesn't have a callback, you can call the method after a delay using:
[self performSelector:#selector(removeFromSuperview) withObject:nil afterDelay:0.25f];
where 0.25f is the delay you want to use. I chose 0.25 because that is the default animation length for animation blocks (as shown above).