I have this code:
successview is my view and it start with alpha 0.00 but when it finish the animation with autoreverse, successview become with alpha 1.00...why?
[UIView beginAnimations:nil context:NULL];
[UIView setAnimationDuration:2];
[UIView setAnimationRepeatAutoreverses:YES];
[successView setAlpha:1.00];
[UIView commitAnimations];
One approach is to do two different animations: One that progresses towards an alpha value of 1.0 and then another that goes from 1.0 back to 0.
Use the animateWithDuration:animations:completion: method of the UIView to accomplish this. You can do the reverse in the completion block.
Something along the lines of:
[UIView animateWithDuration:0.2
animations:^{view.alpha = 1.0;}
completion:^(BOOL finished){
[UIView animateWithDuration:0.2
animations:^{view.alpha = 0;}];
}];
See UIView documentation for more details on animations.
It's in the docs:
If you combine autoreversing with a repeat count (settable using the setAnimationRepeatCount: method), you can create animations that shift back and forth between the old and new values a specified number of times. However, remember that the repeat count indicates the number of complete cycles. If you specify a whole number such as 2.0, the animation ends on the old value, which is followed by the view immediately updating itself to show the new value, which might be jarring. If you want the animation to end on the new value (instead of the old value), add 0.5 to the repeat count value. This adds an extra half cycle to the animation.
Update: read wrong your code, but docs suggest that you use animateWithDuration:delay:options:animations:completion: instead if you are targeting iOS 4.0 and later.
If someone is interested, here's Swift code:
UIView.animate(withDuration: 0.2, animations: {
view.alpha = 1
}) { (finished) in
UIView.animate(withDuration: 0.2, animations: {
view.alpha = 0
})
}
Related
I have a problem with the setting UIViewAnimationOptionAutoReverse.
Here is my code.
CALayer *aniLayer = act.viewToChange.layer;
[UIView animateWithDuration:2.0 delay:1.0 options:(UIViewAnimationCurveLinear | UIViewAnimationOptionAutoreverse) animations:^{
viewToAnimate.frame = GCRectMake(1,1,100,100);
[aniLayer setValue:[NSNumber numberWithFloat:degreesToRadians(34)] forKeyPath:#"transform.rotation"];
} completion:nil ];
The problem is that, after the animation has reversed, the view jumps back to the frame set in the animation block. I want the view to grow and "ungrow" and stop at its original position.
Is there a solution without programming two consecutive animations?
You have three options.
When you use the -[UIView animateWithDuration:…] methods, the changes you make in the animations block are applied immediately to the views in question. However, there is also an implicit CAAnimation applied to the view that animates from the old value to the new value. When a CAAnimation is active on a view, it changes the displayed view, but does not change the actual properties of the view.
For example, if you do this:
NSLog(#"old center: %#", NSStringFromCGPoint(someView.center));
[UIView animateWithDuration:2.0 animations: ^{ someView.center = newPoint; }];
NSLog(#"new center: %#", NSStringFromCGPoint(someView.center));
you will see that 'old center' and 'new center' are different; new center will immediately reflect the values of newPoint. However, the CAAnimation that was implicitly created will cause the view to still be displayed at the old center and smoothly move its way to the new center. When the animation finishes, it is removed from the view and you switch back to just seeing the actual model values.
When you pass UIViewAnimationOptionAutoreverse, it affects the implicitly created CAAnimation, but does NOT affect the actual change you're making to the values. That is, if our example above had the UIViewAnimationOptionAutoreverse defined, then the implicitly created CAAnimation would animate from oldCenter to newCenter and back. The animation would then be removed, and we'd switch back to seeing the values we set… which is still at the new position.
As I said, there are three ways to deal with this. The first is to add a completion block on the animation to reverse it, like so:
First Option
CGPoint oldCenter = someView.center;
[UIView animateWithDuration:2.0
animations: ^{ someView.center = newPoint; }
completion:
^(BOOL finished) {
[UIView animateWithDuration:2.0
animations:^{ someView.center = oldCenter; }];
}];
Second Option
The second option is to autoreverse the animation like you're doing, and set the view back to its original position in a completion block:
CGPoint oldCenter = someView.center;
[UIView animateWithDuration:2.0
delay:0
options: UIViewAnimationOptionAutoreverse
animations: ^{ someView.center = newPoint; }
completion: ^(BOOL finished) { someView.center = oldCenter; }];
However, this may cause flickering between the time that the animation autoreverse completes and when the completion block runs, so it's probably not your best choice.
Third Option
The last option is to simply create a CAAnimation directly. When you don't actually want to change the final value of the property you're changing, this is often simpler.
#import <QuartzCore/QuartzCore.h>
CABasicAnimation *animation = [CABasicAnimation animationWithKeyPath:#"position"];
animation.autoreverses = YES;
animation.repeatCount = 1; // Play it just once, and then reverse it
animation.toValue = [NSValue valueWithCGPoint:newPoint];
[someView.layer addAnimation:animation forKey:nil];
Note that the CAAnimation way of doing things never changes the actual values of the view; it just masks the actual values with an animation. The view still thinks it's in the original location. (This means, for example, that if your view responds to touch events, it will still be watching for those touch events to happen at the original location. The animation only changes the way the view draws; nothing else.
The CAAnimation way also requires that you add it to the view's underlying CALayer. If this scares you, feel free to use the -[UIView animateWithDuration:…] methods instead. There's additional functionality available by using CAAnimation, but if it's something you're not familiar with, chaining UIView animations or resetting it in the completion block is perfectly acceptable. In fact, that's one of the main purposes of the completion block.
So, there you go. Three different ways to reverse an animation and keep the original value. Enjoy!
Here's my solution. For 2x repeat, animate 1.5x and do the last 0.5x part by yourself:
[UIView animateWithDuration:.3
delay:.0f
options:(UIViewAnimationOptionRepeat|
UIViewAnimationOptionAutoreverse)
animations:^{
[UIView setAnimationRepeatCount:1.5f];
... animate here ...
} completion:^(BOOL finished) {
[UIView animateWithDuration:.3 animations:^{
... finish the animation here ....
}];
}];
No flashing, works nice.
There is a repeatCount property on CAMediaTiming. I think you have to create an explicit CAAnimation object, and configure it properly. The repeatCount for grow and ungrow would be 2, but you can test this.
Something a long the lines of this. You would need two CAAnimation objects though, one for the frame and one for the rotation.
CABasicAnimation *theAnimation;
theAnimation=[CABasicAnimation animationWithKeyPath:#"transform.rotation"];
theAnimation.duration=3.0;
theAnimation.repeatCount=1;
theAnimation.autoreverses=YES;
theAnimation.fromValue=[NSNumber numberWithFloat:0.0];
theAnimation.toValue=[NSNumber numberWithFloat:degreesToRadians(34)];
[theLayer addAnimation:theAnimation forKey:#"animateRotation"];
AFAIK there is no way to avoid programming two animation objects.
Here is a Swift version of #Rudolf Adamkovič's answer, where you set the animation to run 1.5 times and in the completion block run a 'reverse' animation one final time.
In the below snippet I am translating my view by -10.0 pts on the y-axis 1.5 times. Then in the completion block I animate my view one final time back to its original y-axis position of 0.0.
UIView.animate(withDuration: 0.5, delay: 0.5, options: [.repeat, .autoreverse], animations: {
UIView.setAnimationRepeatCount(1.5)
self.myView.transform = CGAffineTransform(translationX: 0.0, y: -10.0)
}, completion: { finished in
UIView.animate(withDuration: 0.5, delay: 0, options: [], animations: {
self.myView.transform = CGAffineTransform(translationX: 0.0, y: 0.0)
}, completion: nil)
})
So I want to do a UI animation where a view gradually fades out. Right now I have something like this
[UIView animateWithDuration:2.0f
animations:^{
myView.alpha = 0.0f;
}
];
So right now over the course of those 2 seconds, the view will linearly gradually fade out. However I want to make it so that the fade out is non-linear. For instance, I want it to start fading out slowly and then fade more quickly over time.
How would I do this?
Use one of the longer forms of animateWithDuration methods that take an options parameter, like animateWithDuration:delay:options:animations:completion:.
One of the options you can supply is a timing curve like UIViewAnimationOptionCurveEaseInOut.
Your choices are
UIViewAnimationOptionCurveEaseInOut = 0 << 16,
UIViewAnimationOptionCurveEaseIn = 1 << 16,
UIViewAnimationOptionCurveEaseOut = 2 << 16,
UIViewAnimationOptionCurveLinear = 3 << 16,
If you use CAAnimation instead of UIView animation, you can also create your own custom timing function using the control points of a bezier curve that describes the desired timing function. However, CAAnimation is more complex to use and less well documented.
[UIView animateWithDuration:2.0 delay:0.0 options:UIViewAnimationOptionCurveEaseInOut animations:^{
myView.alpha = 0.0f;
} completion:nil];
Or pick your favorite time curve instead of UIViewAnimationOptionCurveEaseInOut
You must be needing about "ease in" timing curve in which the animation starts slowly and ends as linear. Try the below code,
[UIView animateWithDuration:2.0 delay:0.0 options:UIViewAnimationOptionCurveEaseIn animations:^{
myView.alpha = 0.0f;
} completion:nil];
Please do let me know, if it solves your problem.
I'm running this code...
[UIView animateWithDuration:0.2
delay:0.0
options:UIViewAnimationOptionCurveEaseOut
animations:^{
CGAffineTransform settingsTransform = CGAffineTransformMakeTranslation(self.settingsView.frame.size.width, 0);
CGAffineTransform speedTransform = CGAffineTransformMakeTranslation(-self.speedView.frame.size.width, 0);
self.settingsView.transform = settingsTransform;
self.speedView.transform = speedTransform;
} completion:nil];
But when it runs the views jump half the transform in the opposite direction before sliding to half a position in the correct direction.
I've slowed down the animation duration to 5 seconds but the initial jump is instantaneous and half the transformation in the wrong direction.
When I animate back using this code...
[UIView animateWithDuration:0.2
delay:0.0
options:UIViewAnimationOptionCurveEaseOut
animations:^{
self.settingsView.transform = CGAffineTransformIdentity;
self.speedView.transform = CGAffineTransformIdentity;
} completion:nil];
It does exactly the same thing.
The result is that the final movement is half the desired transform as it jumps half the transform in the wrong direction first.
I really can't work out why this is happening?
Any ideas.
::EDIT::
Clearing up some possible ambiguity.
I'm not trying to have these views "bounce" back to where they are. The views I'm animating are like control panel at the edge of the screen. When the user presses "go" the view then slide out of the way. When the user presses "stop" the panels slide back into the view.
At least they used to. Since enabling auto layout (which I need for other parts of the app) I can't just change the frame of the views so I went the the transform route.
You can see this effect by sticking a view into a view controller and a button to run the animation.
Thanks
I had the exact same problem so here is the solution I came up with.
CGAffineTransform transform = CGAffineTransformMake(1, 0, 0, 1, translation.x, translation.y);
[UIView animateWithDuration:0.25 animations:^{
_assetImageView.transform = transform;
[self.view layoutIfNeeded];
} completion:^(BOOL finished) {
}];
So I call [self.view layoutIfNeeded]; inside of the animate block. Without this the it has the same problem as you and jumps the distance negative translation first then animates to the correct position from there. I am calling this from a view controller so self is a sub class of UIViewController. In your case "self.view" may not exist but I hope you get the idea.
None of the solutions here worked for me... My animation would always skip. (except when it was right at the end of another animation, hint).
Some details:
The view that was doing this had a series of scale and translates already in the stack.
Solution:
Doing a keyframe animation, with a super short first key that would basically re apply the transform that that the last animation should have set.
UIView.animateKeyframesWithDuration(0.4, delay: 0.0, options: [.CalculationModeCubic], animations: { () -> Void in
//reset start point
UIView.addKeyframeWithRelativeStartTime(0.0, relativeDuration: 0.01, animations: { () -> Void in
self.element.transform = initialTransform
})
UIView.addKeyframeWithRelativeStartTime(0.01, relativeDuration: 0.99, animations: { () -> Void in
self.element.transform = finalTransform
})
}, completion: nil)
OK, having watched the WWDC videos again they state that one of the first things you have to do when using AutoLayout is to remove any calls for setFrame.
Due to the complexity of the screen I have removed the Auto-Layout completely and I'm now using the frame location to move the view around the screen.
Thanks
I've asked Apple Technical Support about this issue and got this response, so it's a bug.
iOS 8 is currently exhibiting a known bug in UIKit animations where
transform animations get the wrong fromValue (primarily affecting the
position of animated objects, making them appear to “jump”
unexpectedly at the start on an animation).
[...]
The workaround until a potential fix is delivered is to drop down to
Core Animation APIs to code your animations.
Here's improved version of Andreas answer
The key difference is that you can specify just one keyframe and get less code
UIView.animateKeyframes(withDuration: animationDuration, delay: 0.0, options: [], animations: {
UIView.addKeyframe(withRelativeStartTime: 0.0, relativeDuration: 1.0, animations: {
animatedView.transform = newTransform
})
}, completion: nil)
Does your settingsView or speedView already have a transformation applied before this animation takes place?
If the transformations for these views is not the identity transformation (aka CGAffineTransformIdentity, aka no transformation), you cannot access their .frame properties.
UIViews' frame properties are invalid when they have a transformation applied to them. Use "bounds" instead.
Since you want your second animation to occurs from the current state of your first animation (whether it is finished or not) I recommend to use the UIViewAnimationOptionLayoutSubviews option when setting your second animation.
[UIView animateWithDuration:0.2
delay:0.0
options:UIViewAnimationOptionCurveEaseOut|UIViewAnimationOptionLayoutSubviews
animations:^{
self.settingsView.transform = CGAffineTransformIdentity;
self.speedView.transform = CGAffineTransformIdentity;
} completion:nil];
Here is a sample of the code i used for testing by using the simple view controller template:
myviewcontroller.m:
- (void)viewDidLoad
{
[super viewDidLoad];
self.animatedView = [[UIView alloc] initWithFrame:CGRectMake(20, 20, 160, 80)];
self.animatedView.backgroundColor = [UIColor yellowColor];
[UIView animateWithDuration:0.2
delay:0.0
options:UIViewAnimationOptionCurveEaseOut|UIViewAnimationOptionLayoutSubviews
animations:^{
CGAffineTransform settingsTransform = CGAffineTransformMakeTranslation(self.animatedView.frame.size.width, 0);
self.animatedView.transform = settingsTransform;
}
completion:nil];
self.buttonToTest = [UIButton buttonWithType:UIButtonTypeRoundedRect];
self.buttonToTest.frame = CGRectMake(90, 20, 80, 40);
[self.buttonToTest setTitle:#"Click Me!" forState:UIControlStateNormal];
[self.buttonToTest addTarget:self action:#selector(buttonClicked) forControlEvents:UIControlEventTouchUpInside];
// set-up view hierarchy
[self.view addSubview:self.buttonToTest];
[self.view addSubview: self.animatedView];
}
- (void) buttonClicked
{
[UIView animateWithDuration:.2
delay:0.0
options:UIViewAnimationOptionCurveEaseOut|UIViewAnimationOptionBeginFromCurrentState|UIViewAnimationOptionLayoutSubviews
animations:^{
self.animatedView.transform = CGAffineTransformIdentity;
}
completion:nil];
}
I had this problem and solved it by:
Hide the original view
Add a temp view that copies the view you want to animate
Carry out animation which will now be as intended
Remove the temp view and unhide the original view with the final state
Hope this helps.
I tried the answers above, about the layoutIfNeeded, but it didn't work.
I added the layoutIfNeeded outside (before) the animation block and it solved my problem.
view.layoutIfNeeded()
UIView.animate(withDuration: duration, delay: 0, options: .beginFromCurrentState, animations: {
// Animation here
})
I've made something like:
[UIView animateWithDuration:2.0
delay:0
options:UIViewAnimationOptionRepeat
animations:^{
NSLog(#"Repeating...");
/** code **/
}
completion:^(BOOL finished) {
/** code **/
}];
But the animation does not repeat itself.
Am I missing something?
I've removed the color animation, but the animation doesn't repeat yet. But I must be doing something really wrong, 'cause I tried the following simple code and the animation still doesn't repeat:
[UIView animateWithDuration:1.0f
delay:0
options: UIViewAnimationOptionRepeat
animations:^{
NSLog(#"Repeating...");
self.alpha = 1;
}
completion:nil];
Depending on the animation (still would like to see your code) you might have to reverse your animation in order for it to repeat. For example, if your animation changes an alpha value from 0 to 1, repeating that, without reversing the alpha back to 0, isn't going to do much. You may need to add UIViewAnimationOptionAutoreverse to your animation options.
I have the following block of code to fade out an introView(UIView)
// Hide intro view after 5 seconds
[UIView animateWithDuration: 1.0
delay: 5.0
options: (UIViewAnimationOptionAllowUserInteraction |UIViewAnimationOptionCurveLinear)
animations: ^{
introView.alpha = 0;
}
completion: ^(BOOL finished) {
[introView removeFromSuperview];
}];
I have a skip button inside the introVew but there is no interaction whatsoever, am I missing something? I have to add this is a Universal app targeting 3.2 and I'm using XCode 4.2
Pretty sure this is impossible pre-4.0:
UIView userInteractionEnabled Docs
During an animation, user interactions are temporarily disabled for
all views involved in the animation, regardless of the value in this
property. You can disable this behavior by specifying the
UIViewAnimationOptionAllowUserInteraction option when configuring the
animation.
There seems little point in targeting 3.2 in an app you haven’t released yet.
Are you setting your button alpha to 0?
If yes here is an interesting thing about animation.
What you see on the screen during the animation is not what the application sees.
The moment you set your alpha to 0, the alpha is 0 for that view, even if you are still seeing it on the screen.
Also, a view that has an alpha lower that 0.05 (don't recall the exact number) won't get touch event.
What you can do is to implement the - (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event of that view's superview. or the touchesEnded... as you like.
(Assuming that your not setting it's alpha to 0.)
So you can test for touche that occur where the button is, or just remove that button and let any touch on the screen cancel your animation.
You may also be interested in this post:
Core Animation, unexpected animated position and hitTest values
I found another circumstance which could cause this. I haven't seen this answer anywhere else. It does not deal with alpha at all.
If you use a delay in the call to UIView.animate(), then even if you specify the .allowUserInteraction option, the view does NOT receive touches during the delay period. I have no idea why, but I could help it by moving the code block to another function, and using a performSelector after the same delay seconds, and in the block I run the code without delay.
I had the same problem with a button that I animated with changing the alpha. Cueing off VinceBurn's answer...
What you see on the screen during the animation is not what the application sees. The moment >you set your alpha to 0, the alpha is 0 for that view, even if you are still seeing it on the >screen.
AND view that have an alpha lower that 0.05 (don't recall the exact number) won't get touch >event.
… the simple solution of just making the minimum alpha 0.1 instead of 0.0 worked for me:
[UIView animateWithDuration:0.5
delay:0.0
options:UIViewAnimationOptionCurveEaseInOut | UIViewAnimationOptionRepeat | UIViewAnimationOptionAutoreverse | UIViewAnimationOptionAllowUserInteraction
animations:^{
self.myButton.alpha = 0.1f;
}
completion:^(BOOL finished){
}]
Button registered the touchUpInside all the time with no additional method needed, and there was virtually no difference in appearance from taking the alpha to zero.
This won't work in iOS 3.2 since Blocks are only available in iOS4
you will have to use the standard animation techniques, in a separate thread so that you don't block the interface
[UIView beginAnimations:nil context:nil];
[UIView setAnimationTransition: UIViewAnimationTransitionFlipFromLeft forView:view cache:YES];
[UIView setAnimationCurve:UIViewAnimationCurveEaseInOut];
[UIView setAnimationDuration:1.0];
[view1 setHidden:TRUE];
[UIView commitAnimations];