After using [self.view.layer removeAllAnimations], the next animation not working - ios

The problem is when I'm using:
[transLabel.layer removeAllAnimations];
(transLabel is a UILabel that show the information)
After that, I try to add a new animation to this Label
[UIView animateWithDuration:showTime
animations:^{
transLabel.hidden = NO;
transLabel.transform = CGAffineTransformMakeScale(1.5, 1.5);
}
completion:^(BOOL finished) {
transLabel.hidden = YES;
transLabel.transform = CGAffineTransformMakeScale(1.0, 1.0);
}];
But It didn't work anymore, it just work at odd number click. Like, first time it works, and second time it doesn't work, but third time it shows again, forth not, fifth yes..
What I want to do is keep pushing down one button again again again
and the Label is show again again again with animation
Thank you and wait for your answer

If i understood your question correctly, the problem occurs because the presentation layer do all the animations and are the layer that actually performs all the animations. When you cancel an ongoing animation that is reflected upon the presentation layer and not the view layer. Try capturing the changes to the view's layer and see if that helps you in this case:
transLabel.layer.transform = transLabel.layer.presentationLayer.transform;

I just had a similar issue. The problem is that when you stop animation you hide your transLabel.
Show it right after [transLabel.layer removeAllAnimations]; like this:
[transLabel.layer removeAllAnimations];
transLabel.hidden = NO;

Related

Animate image change of UIImageView when having an UIVisualEffectView above

My problem is as follows:
An UIImageView's view is going to be changed with an animation, like this:
[UIView transitionWithView:_backgroundArtworkImageView
duration:ANIMATION_DURATION
options:UIViewAnimationOptionTransitionCrossDissolve
animations:^{
_backgroundArtworkImageView.image = blurredImage;
}
completion:nil];
It works perfectly fine as long as I don't have an UIVisualEffectView over the image view. If using the blur view on top, it results in no animation at all.
I've looked around for a bit and seen that snapshots of views could be something to look into, which also seems to be what Apple uses internally on iOS, for example when bringing up the app switcher; I'm not really sure how exactly to approach it though.
Got it working by taking a snapshot, append it to the superview, hide the real view, change it without animation and then fade the real view in with animation.
__block UIView *snapshot = [_backgroundArtworkImageView snapshotViewAfterScreenUpdates:NO];
[_artworkContainer insertSubview:snapshot belowSubview:_backgroundArtworkImageView];
_backgroundArtworkImageView.alpha = 0.0f;
_backgroundArtworkImageView.image = blurredImage;
[UIView transitionWithView:_artworkContainer
duration:ANIMATION_DURATION
options:UIViewAnimationOptionTransitionCrossDissolve
animations:^{
_backgroundArtworkImageView.alpha = 1.0f;
}
completion:^(BOOL _) {
[snapshot removeFromSuperview];
snapshot = nil;
}];
Edit: I realized that the blur view was taking a small time to update, but to solve that a new snapshot of the resulting view could be taken and then animated with.

How to force a view animation to finish before executing sendSubviewToBack?

I am building a page browser that animates pages as 'sheets of paper' being pulled on top of off a stack of papers. In order to keep smooth animations I use 3 UIViews which are stacked on top of each other. These three views hold the current page (on top), the previous page (in the middle) and the next page (at the bottom).
In the code below, I want to drag the top view off to the right, revealing the previous page underneath. This works fine. However, after that I need to move the top page to the bottom of the stack, in order to prepare the stack of three views for the next time the user does a page flip. I use the sendSubviewToBack method for this.
My problem is that ViewSample[Top] is sent to the bottom of the stack as soon as the animation starts. How can I enforce the animation to finish (so that ViewSample[Top] has moved out of the screen completely) before it is sent to the bottom of the stack?
ViewSample[Top].center = CGPointMake(x,y);
[UIView animateWithDuration:0.5
animations:^
{
ViewSample[Top].center = CGPointMake(x+w,y); //slide away to the right
}
completion:^(BOOL finished)
{
}
];
[self.MainView sendSubviewToBack:ViewSample[Top]];
EDIT
i just ran into a very peculiar behaviour which has to do with my problem.
I followed your advice, and found that the behaviour in the 'finished' section of the animation depends on the value of the variable 'top' when it is set AFTERWARDS:
ViewSample[Top].center = CGPointMake(x,y);
[UIView animateWithDuration:0.5
animations:^
{
ViewSample[Top].center = CGPointMake(x+w,y); //slide away to the right
}
completion:^(BOOL finished)
{ [self.MainView sendSubviewToBack:ViewSample[Top]];
}
];
Top++; // THIS COMMAND AFFECTS THE LINE ABOVE!!!
In other words, when I add the line 'Top++;' another View is moved back on the stack, even though the statement sendSubviewToBack came first. This is very confusing to me. Does this make sense? Is it a bug?
The other answers correctly identified the issue. What you're running into with your updated code is a problem of execution order:
Because completion is executed only after the animation completes, your code actually executes in this order:
ViewSample[Top].center = CGPointMake(x,y);
ViewSample[Top].center = CGPointMake(x+w,y);
Top++;
[self.MainView sendSubviewToBack:ViewSample[Top]];
There are two possible solutions. You can either store the view in a variable so you have the same view in all your calls, or you can delay setting the value of Top until completion.
Option 1
UIView *viewMovingFromTopToBottom = ViewSample[Top];
viewMovingFromTopToBottom.center = CGPointMake(x,y);
[UIView animateWithDuration:0.5 animations:^{
viewMovingFromTopToBottom.center = CGPointMake(x+w,y); //slide away to the right
} completion:^(BOOL finished) {
[self.MainView sendSubviewToBack:viewMovingFromTopToBottom];
}];
Top++;
// Other code that depends on the new value of Top...
Option 2
ViewSample[Top].center = CGPointMake(x,y);
[UIView animateWithDuration:0.5 animations:^{
ViewSample[Top].center = CGPointMake(x+w,y); //slide away to the right
} completion:^(BOOL finished) {
[self.MainView sendSubviewToBack:ViewSample[Top]];
Top++;
// Other code that depends on the new value of Top...
}];
Which option makes the most sense to you depends on what you're doing. If you're chaining animations together, you may want to move most of your code into the completion block to delay it until the slide animation completes. If you have a lot of work that needs to be done right away without dependencies on animation, you may want to use option 1 to configure you animations and move on. Or you may want a mix.
Use the completion block:
ViewSample[Top].center = CGPointMake(x,y);
[UIView animateWithDuration:0.5
animations:^
{
ViewSample[Top].center = CGPointMake(x+w,y); //slide away to the right
}
completion:^(BOOL finished)
{
[self.MainView sendSubviewToBack:ViewSample[Top]];
}
];
Brian Nickel's first suggestion (local variable) did the trick. However, there was a caveat: you have to be careful in the order of statements. This does not work:
[self.MainView addSubview:LocalView];
LocalView = View[1];
...whereas this does:
LocalView = View[1];
[self.MainView addSubview:LocalView];
I first had the top version, which just makes the blank view appear.
So a working approach is to use three global views to do the page caching, and use two local views for the animation. The local views are stacked in the appropriate order, copy the data from the global views and then perform the animation.

Cancelling UIView Animation - self.view.layer removeAllAnimations not working

I've got a UIView Animation going on that I need to cancel in my iOS app. I've tried this:
[self.view.layer removeAllAnimations];
But it didn't work. The animation continued. Here is my animation code:
[UIView animateWithDuration:1.4 delay:0 options:UIViewAnimationOptionCurveEaseOut animations:^{
recognizer.view.transform = CGAffineTransformTranslate(recognizer.view.transform, translation.x, translation.y);
} completion:^(BOOL finished) {
NSLog(#"completed animation, now do whatever");
}];
Does anybody have any ideas as to why it's not working?
You are adding that animation to recognizer's view, hence you will have to remove it from that same view's layer.
So instead of
[self.view.layer removeAllAnimations];
you may want to
[recognizer.view.layer removeAllAnimations];
And to keep the current status of the transformation, fetch that one from the presentation layer. The presentation layer is the one that actually reflects the changes during the animation.
recognizer.view.layer.transform = recognizer.view.layer.presentationLayer.transform;
Ok - just figured it out. Changed the component beng animated from the gesture recogniser on top of the image view to the image view itself. Now, just before the code to stop the animation, I have:
truckView.frame = [[trackView.layer presentationLayer] frame];
[truckView.layer removeAllAnimations];
So this is the way to do it. Thanks for the help that led me to this answer,
Sam

When customView transition animation, it can't receive gesture

[UIView transitionWithView:imageView
duration:3.0
options:UIViewAnimationOptionTransitionCrossDissolve
animations:^{
imageView.image = [UIImage imageNamed:[welcomePhoto objectAtIndex:photoCount]];
}
completion:^(BOOL finish){
}];
When the animation transition at the three second,
imageView can't receive custom gesture,
other times is fine.
How can i fix it? Thanks.
The reason : when UIView animation starts from one point to another, the actual view goes to the new position straight away but it is just hidden. And the view you see moving is just an illusion.
My Given reason is based on paul hagerty's stanford lecture about animation.
The solution to this can be found in other given answer.

ios MapKit MKOverlayView animation happening instantly

I am trying to animate the alpha value of a MapKit overlay view (specifically an MKCircleView) in iOS 5 using the following code:
-(void) animateCircle:(MKCircle*)circle onMap:(MKMapView*) mapView
{
MKCircleView * circleView = (MKCircleView*) [mapView viewForOverlay:circle];
UIViewAnimationOptions options = UIViewAnimationOptionCurveEaseInOut|UIViewAnimationOptionTransitionNone;
[UIView animateWithDuration:5.0
delay:0.0
options:options
animations:^(void) { circleView.alpha = 0.9; }
completion:^(BOOL finished) {}
];
}
The alpha value of the overlay is changing as I want, but it is jumping there instantaneously rather than animating over the specified duration.
Can anyone suggest what might be wrong? Perhaps animation on overlay views os more complex with blocks than I had thought.
Core Animation has interesting behavior when concurrent animations effect the same view... If you try to animate a view before the view's last animation finished, it will assume you intended the subsequent animation to start from the desired end-state of the initial one. This can result in jumps of frames as well as jumps of alpha values.
In your case, this view is likely being animated by something else. Try locating and removing the other animation / or'ing in UIViewAnimationOptionBeginFromCurrentState to its options.

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