I have a rotating circle shape with 5 subviews and I am animating changes to its fillcolor to match the subview that is currently on top. So when I have to change the color I remove animations from that layer and then add the new one like this:
[self.dynamicColorCircleLayer removeAllAnimations]; //checked - doesn't matter if line is added or not
switch (index) {
case 0: {
CABasicAnimation *fillColorAnimation = [CABasicAnimation animationWithKeyPath:#"fillColor"];
fillColorAnimation.duration = 2;
//fillColorAnimation.fromValue = (id)self.dynamicColorCircleLayer.fillColor;
fillColorAnimation.toValue = (id)[[UIColor redColor] CGColor];
fillColorAnimation.removedOnCompletion = NO;
fillColorAnimation.fillMode = kCAFillModeForwards;
fillColorAnimation.delegate = self;
[self.dynamicColorCircleLayer addAnimation:fillColorAnimation forKey:#"fillColor"];
etc.
And the delegate method:
- (void)animationDidStop:(CAAnimation *)theAnimation finished:(BOOL)flag {
self.dynamicColorCircleLayer.fillColor = (__bridge CGColorRef)(((CABasicAnimation*)theAnimation).toValue);
}
However when one animation hasn't ended and I have to start another, the new one immediately ends.
Fore example: I am animating color change from red to blue, I'm in the middle of animation and I have to animate color change to green. The animation isn't showing, circle just immediately changes color to green.
If I remove code from animationDidStop(...), I will get an animation to green, but every animation will start from the default (red) color.
What is the right way to interrupt animation with another animation? Also, is it even possible to make the new animation start from the color it had at the moment when I removed the older animation? (In the example above, it would be animating color change to green from a color between red and blue)
Refer this question:
Is there a way to pause a CABasicAnimation?
Here first answer explains how to pause existing animation and the second answer says how to stop the same.
Hope this is what you are looking for.
I found a way to do this, however I still have no idea how to start the next animation from the color at which the previous one was stopped. Here it is in case anyone will need it:
CABasicAnimation *currentAnimation = (CABasicAnimation*)[self.dynamicColorCircleLayer animationForKey:#"fillColor"];
if (currentAnimation != nil) {
self.dynamicColorCircleLayer.fillColor = (__bridge CGColorRef)(currentAnimation.toValue);
}
switch (index) {
case 0: {
CABasicAnimation *fillColorAnimation = [CABasicAnimation animationWithKeyPath:#"fillColor"];
fillColorAnimation.duration = 2.5f;
fillColorAnimation.toValue = (id)[[UIColor redColor] CGColor];
fillColorAnimation.removedOnCompletion = NO;
fillColorAnimation.fillMode = kCAFillModeForwards;
fillColorAnimation.delegate = self;
[self.dynamicColorCircleLayer addAnimation:fillColorAnimation forKey:#"fillColor"];
break;
} (...)
And in the delegate method:
- (void)animationDidStop:(CAAnimation *)theAnimation finished:(BOOL)flag {
if (flag) {
self.dynamicColorCircleLayer.fillColor = (__bridge CGColorRef)(((CABasicAnimation*)theAnimation).toValue);
}
}
Now, when i.e. animation that changes color to green is either succesfully finished or interrupted early, fillcolor will just change to green and begin next animation if needed.
Related
I'm animating UIImageView using iOS core animation "CABasicAnimation", all works fine for me but the only problem is when i animate to the position, after completeing animation it comes back to original position where it was. how can i overcome this? i need to keep UIImageView in moved position.
NOTE : I've seen few questions with success answers regarding this, but i have no idea why mine is not working like they say.
After rotating a CALayer using CABasicAnimation the layer jumps back to it's unrotated position
Here is my sample code,
CGPoint endPt = CGPointMake(160, 53);
CABasicAnimation *anim5 = [CABasicAnimation animationWithKeyPath:#"position"];
[anim5 setBeginTime:CACurrentMediaTime()+0.4];
anim5.timingFunction = [CAMediaTimingFunction functionWithName:kCAMediaTimingFunctionEaseOut];
anim5.fromValue = [NSValue valueWithCGPoint:imgRef.layer.position];
anim5.toValue = [NSValue valueWithCGPoint:endPt];
anim5.duration = 1.5;
anim5.speed = 2;
[imgRef.layer addAnimation:anim5 forKey:#"position"];
//this is what other answers ask to do
[anim5 setFillMode:kCAFillModeForwards];
[anim5 setRemovedOnCompletion:NO];
BTW [imgRef.layer setPosition:CGPointMake(160, 53)]; won't help me since i'm delaying animation with 4 milliseconds.
The root cause is that the animation just transitions the property between two values, it doesn't actually change the ending value. You need to change the ending value when the animation completes, there are three ways to do that.
1) Use the delegate property on the CAAnimation superclass to be notified of when the animation completes. At that point you can set the property to it's end value. See: https://developer.apple.com/library/mac/#documentation/GraphicsImaging/Reference/CAAnimation_class/Introduction/Introduction.html#//apple_ref/occ/cl/CAAnimation The animationDidStop:finished: is the method you'll need to implement on the delegate.
2) Set a completion block on the surrounding CATransaction. You'll need to manually start the CATransaction rather than having CABasicAnimation do that automatically for you. See: Objective-C - CABasicAnimation applying changes after animation?
3) See OMZ's comment below...
The right answer is to set the layer's position property, but as you've pointed out, it makes it more difficult because you're wanting a 0.4 second delay prior to the position change. Is there any reason you couldn't perform the delay first and then do the animation? Something like this:
- (IBAction)didTapMove:(id)sender
{
[self performSelector:#selector(animate) withObject:nil afterDelay:0.4];
}
- (void)animate
{
CGPoint endPt = CGPointMake(160, 53);
CABasicAnimation *anim5 = [CABasicAnimation animationWithKeyPath:#"position"];
anim5.timingFunction = [CAMediaTimingFunction functionWithName:kCAMediaTimingFunctionEaseOut];
anim5.fromValue = [NSValue valueWithCGPoint:_imageView.layer.position];
anim5.toValue = [NSValue valueWithCGPoint:endPt];
anim5.duration = 1.5;
anim5.speed = 2;
[_imageView.layer addAnimation:anim5 forKey:#"position"];
[_imageView.layer setPosition:CGPointMake(160, 53)];
}
Noticed I've removed your begin time from the animation since the delay is occurring in the perform selector call.
I've hit a wall here. I know how to move an Image using "CGAffineTransformMakeTranslation" and I also know how to scale an image using"CGAffineTransformMakeScale" but for the life of me, I can't seem to get one Image to do both of these and stay that way. It scales to the desired size for about a split second and then immediately reverts to its original size and moves to the desired location. What I need is for the image to get big, STAY big, and then move to a new location (while permanently staying its new size).
Here is what I've got going on in my .m file:
-(IBAction)PushZoomButton {
[UIWindow animateWithDuration:1.5
animations:^{
JustinFrame.transform = CGAffineTransformMakeScale(2.0, 2.0);
JustinFrame.transform = CGAffineTransformMakeTranslation(10.0, 10.0);}];
[UIWindow commitAnimations];}
Any help with this would be appreciated!
you can use CGAffineTransformConcat, for instance:
JustinFrame.transform = CGAffineTransformConcat(CGAffineTransformMakeScale(2.0, 2.0), CGAffineTransformMakeTranslation(10.0, 10.0));
You may need to adapt the translation to (5, 5) since you have doubled the scale
The second transform you set overrides the first one. You need to concat both transform actions into one, as Luis said. Another way of writing that would be:
CGAffineTransform transform = CGAffineTransformMakeScale(2.0, 2.0);
transform = CGAffineTransformTranslate(transform, 10, 10);
JustinFrame.transform = transform;
You may need to look into CoreAnimation, basically what UIView animation is controlling under the hood. If you set up a CAAnimation, then what you want to achieve is done with the fillMode property of the animation.
Here's some example code to make a UIView look like it's opening like a door (copy pasted some code I have, but perhaps you could modify it and find it useful):
- (void) pageOpenView:(UIView *)viewToOpen duration:(NSTimeInterval)duration pageTurnDirection:(PageTurnDirection) p{
// Remove existing animations before stating new animation
[viewToOpen.layer removeAllAnimations];
// Make sure view is visible
viewToOpen.hidden = NO;
// disable the view so it’s not doing anythign while animating
viewToOpen.userInteractionEnabled = NO;
float dir = p == 0 ? -1.0f : 1.0f; // for direction calculations
// create an animation to hold the page turning
CABasicAnimation *transformAnimation = [CABasicAnimation animationWithKeyPath:#"transform"];
transformAnimation.removedOnCompletion = NO;
transformAnimation.duration = duration;
transformAnimation.timingFunction = [CAMediaTimingFunction functionWithName:kCAMediaTimingFunctionEaseIn];
CATransform3D startTransform = CATransform3DIdentity;
if (p == NEXT_PAGE) {
// orig values
startTransform.m34 = 0.001f;
}else {
// orig values
startTransform.m34 = -0.001f;
}
// start the animation from the current state
transformAnimation.fromValue = [NSValue valueWithCATransform3D:startTransform];
// this is the basic rotation by 90 degree along the y-axis
CATransform3D endTransform = CATransform3DMakeRotation(3.141f/2.0f,
0.0f,
dir,
0.0f);
// these values control the 3D projection outlook
if (p == NEXT_PAGE) {
endTransform.m34 = 0.001f;
endTransform.m14 = -0.0015f;
}else {
endTransform.m34 = -0.001f;
endTransform.m14 = 0.0015f;
}
transformAnimation.toValue = [NSValue valueWithCATransform3D:endTransform];
// Create an animation group to hold the rotation
CAAnimationGroup *theGroup = [CAAnimationGroup animation];
// Set self as the delegate to receive notification when the animation finishes
theGroup.delegate = self;
theGroup.duration = duration;
// CAAnimation-objects support arbitrary Key-Value pairs, we add the UIView tag
// to identify the animation later when it finishes
[theGroup setValue:[NSNumber numberWithInt:[(BODBookPageView *)viewToOpen pageNum]] forKey:#"animateViewPageNum"]; //STEPHEN: We set the tag to the page number
[theGroup setValue:[NSNumber numberWithInt: p] forKey:#"PageTurnDirection"];
[theGroup setValue:[NSNumber numberWithBool:YES] forKey:#"isAnimationMidpoint"]; // i.e. is this the first half of page-turning or not?
// Here you could add other animations to the array
theGroup.animations = [NSArray arrayWithObjects:transformAnimation, nil];
theGroup.removedOnCompletion = NO; // THIS LINE AND THE LINE BELOW WERE CRUCIAL TO GET RID OF A VERY HARD TO FIND/FIX BUG.
theGroup.fillMode = kCAFillModeForwards; // THIS MEANS THE ANIMATION LAYER WILL STAY IN THE STATE THE ANIMATION ENDED IN, THEREBY PREVENTING THAT ONE FRAME FLICKER BUG.
// Add the animation group to the layer
[viewToOpen.layer addAnimation:theGroup forKey:#"flipViewOpen"];
}
I've been trying to understand what is wrong with my animation and I still haven't figure it out. I think it should be really straight forward, but there is probably something I'm missing, even after reading lot of examples and documentation.
My problem comes originally form the fact that on the iPhone, you cannot resize layers automatically (with the view). The documentation says otherwise but there is no autoresizeMask for the layer in the SDKs. So I decided to make a little workaround and animate the layer myself.
I've got this simple piece of code that should do a simple resize animation. The values are good and I even set the delegate in order to trace if the anim start/end.
// I've got a property named layerImage (which is a CALayer)
- (void)animateTestWithFrame:(CGRect)value {
CABasicAnimation *animation = [CABasicAnimation animationWithKeyPath:#"layerImage.frame"];
animation.duration = 1;
animation.fromValue = [NSValue valueWithCGRect:self.frame];
animation.toValue = [NSValue valueWithCGRect:value];
animation.removedOnCompletion = YES;
animation.delegate = self;
[self.layer addAnimation:animation forKey:#"layerImage.frame"];
}
So, any ideas? (This view that contains the code is the subview of a subview of the window if that could make a difference)
--- EDIT ---
It seems that frame is not animatable via CABasicAnimation and the named property "frame". When using bounds, I've got some strange result, but at least I'm getting something. Will continue investigating on this.
So it's good that you've figured things out here, but your answer to your own question has some inaccuracies. Let me correct a few things:
The frame property can be animated--just not with explicit animation. If you do the following to a layer other than the root layer of a view, the frame will animate just fine:
[CATransaction begin];
[CATransaction setAnimationDuration:2.0f];
[animationLayer setFrame:CGRectMake(100.0f, 100.0f, 100.0f, 100.0f)];
[CATransaction commit];
Remember that setting a property on a layer will animate that property change by default. In fact you have to disable animations on a property change if you don't want it to animate. (Of course this is only true if you are animating a layer other than the root layer of a view.) You are correct in animating both position and bounds if you need to use an explicit animation.
You can animate the frame on a UIView using implicit animation:
[UIView beginAnimations:nil context:NULL];
[UIView setAnimationDuration:3.0f];
[[self view] setFrame:CGRectMake(45.0f, 45.0f, 100.0f, 100.0f)];
[UIView commitAnimations];
This will animate from the view's current frame (bounds and position) to x = 45.0, y = 45.0, w = 100.0, h = 100.0.
It seems you may also be misunderstanding the difference between an animation and a layer. You add animations to layers, but adding an animation to a layer does not automatically set the property that you're animating.
CALayers are model objects. They contain information about the layer that eventually gets rendered to screen. You must set a layer's property if you want that property to actually have that value. If you simply animate the property, it will only be a visual representation and not actual--which is to say this is why the value snaps back to the original value of the layer because you never actually changed it.
Which leads me to the next point. You said:
Use "animation.removedOnCompletion =
NO; animation.fillMode =
kCAFillModeForwards;" to ensure that
the values are not reseted at the end
of the animation
This is not exactly right. These two values simply cause the animation to remain at it's final position visually, however, the layer's actual values have not changed. They are still the exact same values they were when you started the animation. In general (with a few exceptions) you don't want to use these two parameters because they are visual only. What you want is to actually set the layer value for the property you're animating.
Say, for example, that you want to animate the position of your layer using an explicit animation. Here is the code you want:
CABasicAnimation *animation = [CABasicAnimation animationWithKeyPath:#"position"];
[animation setFromValue:[NSValue valueWithCGPoint:CGPointMake(70.0f, 70.0f)]];
[animation setToValue:[NSValue valueWithCGPoint:CGPointMake(150.0f, 150.0f)]];
[animation setDuration:2.0f];
// Actually set the position on the *layer* that you want it to be
// when the animation finishes.
[animationLayer setPosition:CGPointMake(150.0f, 150.0f)];
// Add the animation for the position key to ensure that you
// override the animation for position changes with your animation.
[animationLayer addAnimation:animation forKey:#"position"];
You may also want to consider animation grouping. With an animation group, you can group several animations together and then control how they relate to each other. In your case the duration for your bounds and position animations are the same and so what you are trying to do will work fine without a group, but if you wanted to offset the start of the animations, for example you didn't want the position animation to start until a second or two into the frame animation, you could stagger them by setting the beginTime value of the position animation.
Finally, I would be curious to know why you couldn't use the implicit animations available on UIView. I use these in the vast majority of the Core Animation code I write and can't see why this wouldn't work for your situation.
Best regards.
The key path should only be the key path of the property, not the name of the object as well.
Use this
[CABasicAnimation animationWithKeyPath:#"frame"]
instead of this
[CABasicAnimation animationWithKeyPath:#"layerImage.frame"]
And just BTW, when you add animation to a layer, the key doen't mean the key property to animate. Just the key (name) that you want this animation to have (this refers to the last line your code)
So, the solution was to animate the #"bounds" and the #"position" of the layer because frame is not animatable on iPhone. It took me some time to understand that the position was the center of the layer and the resize of the bounds was extending from the center, but that was the easy part.
So, what I did in resume was:
In the setFrame, create 2 animations with the bounds and position property.
Use "animation.removedOnCompletion = NO; animation.fillMode = kCAFillModeForwards;" to ensure that the values are not reseted at the end of the animation
Register the delegate to self in order to implements "animationDidStop:finished:". It seems that you still need to set the values: "layerImage.bounds = [animation.toValue CGRectValue]; layerImage.position = [animation.toValue CGPointValue];".
I wasn't able to use the UIView animation system directly because it wasn't doing what I wanted on the layers.
Thanks tadej5553 for pointing me out the layer problem I had with the "addAnimation". So here is the code for those who would like to see what it looks like.
- (void)animationDidStop:(CAAnimation *)anim finished:(BOOL)flag {
CABasicAnimation *animation = (CABasicAnimation*)anim;
if ([animation.keyPath isEqualToString:#"bounds"]) {
layerImage.bounds = [animation.toValue CGRectValue];
} else if ([animation.keyPath isEqualToString:#"position"]) {
layerImage.position = [animation.toValue CGPointValue];
}
}
- (void)setFrame:(CGRect)value {
CGRect bounds = CGRectMake(0, 0, value.size.width, value.size.height);
if ([UIView isAnimationStarted]) {
// animate the bounds
CABasicAnimation *animation = [CABasicAnimation animationWithKeyPath:#"bounds"];
animation.duration = [UIView animationDuration];
animation.fromValue = [NSValue valueWithCGRect:layerImage.bounds];
animation.toValue = [NSValue valueWithCGRect:bounds];
animation.removedOnCompletion = NO;
animation.fillMode = kCAFillModeForwards;
animation.timingFunction = [UIView animationFunction];
animation.delegate = self;
[layerImage addAnimation:animation forKey:#"BoundsAnimation"];
// animate the position so it stays at 0, 0 of the frame.
animation = [CABasicAnimation animationWithKeyPath:#"position"];
animation.duration = [UIView animationDuration];
animation.fromValue = [NSValue valueWithCGPoint:layerImage.position];
animation.toValue = [NSValue valueWithCGPoint:CGPointMake(bounds.size.width / 2, bounds.size.height / 2)];
animation.removedOnCompletion = NO;
animation.fillMode = kCAFillModeForwards;
animation.timingFunction = [UIView animationFunction];
animation.delegate = self;
[layerImage addAnimation:animation forKey:#"PositionAnimation"];
} else {
layerImage.frame = bounds;
}
[super setFrame:value];
}
I have a UIView subclass which uses a CAShapeLayer mask on its CALayer. The mask uses a distinct shape, with three rounded corners and a cut out rectangle in the remaining corner.
When I resize my UIView using a standard animation block, the UIView itself and its CALayer resize just fine. The mask, however, is applied instantly, which leads to some drawing issues.
I've tried animating the mask's resizing using a CABasicAnimation but didn't have any luck getting the resizing animated.
Can I somehow achieve an animated resizing effect on the mask? Do I need to get rid of the mask, or will I have to change something about the way I currently draw the mask (using - (void)drawInContext:(CGContextRef)ctx).
Cheers,
Alex
I found the solution to this problem. Other answers are partially correct and are helpful.
The following points are important to understanding the solution:
The mask property is not animatable itself.
Since the mask is a CALayer it can be animated on its own.
Frame is not animatable, use bounds and position. This may not apply to you(if you weren't trying to animate the frame), but was an issue for me. (See Apple QA 1620)
A view layer's mask is not tied to UIView so it will not receive the core animation transaction that is applied to the view's layer.
We are modifying the CALayer directly, so we can't expect that UIView will have any idea of what we are trying to do, so the UIView animation won't create the core animation transaction to include changes to our properties.
In order to solve, we are going to have to tap into Core Animation ourselves, and can't rely on the UIView animation block to do the work for us.
Simply create a CATransaction with the same duration that you are using with [UIView animateWithDuration:...]. This will create a separate animation, but if your durations and easing function is the same, it should animate exactly with the other animations in your animation block.
NSTimeInterval duration = 0.5;// match this to the value of the UIView animateWithDuration: call
[CATransaction begin];
[CATransaction setValue:[NSNumber numberWithFloat:duration] forKey:kCATransactionAnimationDuration];
self.myView.layer.mask.position = CGPointMake(newX, 0);
self.myView.layer.mask.bounds = CGRectMake(0, 0, newWidth, newHeight);
[CATransaction commit];
I use a CAShapeLayer to mask a UIView by setting self.layer.mask to that shape layer.
To animate the mask whenever the size of the view changes I overwrote the -setBounds: to animate the mask layer path if the bounds are changed during an animation.
Here's how I implemented it:
- (void)setBounds:(CGRect)bounds
{
[super setBounds:bounds];
CAPropertyAnimation *boundsAnimation = (CABasicAnimation *)[self.layer animationForKey:#"bounds"];
// update the mask
self.maskLayer.frame = self.layer.bounds;
// if the bounds change happens within an animation, also animate the mask path
if (!boundsAnimation) {
self.maskLayer.path = [self createMaskPath];
} else {
// copying the original animation allows us to keep all animation settings
CABasicAnimation *animation = [boundsAnimation copy];
animation.keyPath = #"path";
CGPathRef newPath = [self createMaskPath];
animation.fromValue = (id)self.maskLayer.path;
animation.toValue = (__bridge id)newPath;
self.maskLayer.path = newPath;
[self.maskLayer addAnimation:animation forKey:#"path"];
}
}
(For the example self.maskLayer is set to `self.layer.mask)
My -createMaskPath calculates the CGPathRef that I use to mask the view. I also update the mask path in -layoutSubviews.
The mask property of CALayer is not animatable which explains your lack of luck in that direction.
Does the drawing of your mask depend on the frame/bounds of the mask? (Can you provide some code?) Does the mask have needsDisplayOnBoundsChange property set?
Cheers,
Corin
To animate the bounds change of the mask layer of a UIView: subclass UIView, and animate the mask with a CATransaction - similar to Kekodas answer but more general:
#implementation UIMaskView
- (void) layoutSubviews {
[super layoutSubviews];
CAAnimation* animation = [self.layer animationForKey:#"bounds"];
if (animation) {
[CATransaction begin];
[CATransaction setAnimationDuration:animation.duration];
}
self.layer.mask.bounds = self.layer.bounds;
if (animation) {
[CATransaction commit];
}
}
#end
The mask parameter doesn't animate, but you can animate the layer which is set as the mask...
If you animate the CAShapeLayer's Path property, that should animate the mask. I can verify that this works from my own projects. Not sure about using a non-vector mask though. Have you tried animating the contents property of the mask?
Thanks,
Jon
I couldn't find any programmatical solution so I just draw an png image with correct shape and alpha values and used that instead. That way I don't need to use a mask...
It is possible to animate the mask change.
I prefer to use CAShapeLayer as the mask layer. It is very convenient to animate a mask change with the help of property path.
Before animate any change, dump the content of the source into an instance CGImageRef, and create a new layer for animation. Hide the original layer during the animation and show it when animation ends.
The following is a sample code for creating key animation on property path.
If you want to create your own path animation, make sure that there are always same number of points in the paths.
- (CALayer*)_mosaicMergeLayer:(CGRect)bounds content:(CGImageRef)content isUp:(BOOL)isUp {
CALayer* layer = [CALayer layer];
layer.frame = bounds;
layer.backgroundColor = [[UIColor clearColor] CGColor];
layer.contents = (id)content;
CAShapeLayer* maskLayer = [CAShapeLayer layer];
maskLayer.fillColor = [[UIColor blackColor] CGColor];
maskLayer.frame = bounds;
maskLayer.fillRule = kCAFillRuleEvenOdd;
maskLayer.path = ( isUp ? [self _maskArrowUp:-bounds.size.height*2] : [self _maskArrowDown:bounds.size.height*2] );
layer.mask = maskLayer;
CAKeyframeAnimation* ani = [CAKeyframeAnimation animationWithKeyPath:#"path"];
ani.removedOnCompletion = YES;
ani.duration = 0.3f;
ani.fillMode = kCAFillModeForwards;
ani.timingFunction = [CAMediaTimingFunction functionWithName:kCAMediaTimingFunctionEaseInEaseOut];
NSArray* values = ( isUp ?
[NSArray arrayWithObjects:
(id)[self _maskArrowUp:0],
(id)[self _maskArrowUp:-ceilf(bounds.size.height*1.2)],
nil]
:
[NSArray arrayWithObjects:
(id)[self _maskArrowDown:0],
(id)[self _maskArrowDown:bounds.size.height],
nil]
);
ani.values = values;
ani.delegate = self;
[maskLayer addAnimation:ani forKey:nil];
return layer;
}
- (void)_startMosaicMergeAni:(BOOL)up {
CALayer* overlayer = self.aniLayer;
CGRect bounds = overlayer.bounds;
self.firstHalfAni = NO;
CALayer* frontLayer = nil;
frontLayer = [self _mosaicMergeLayer:bounds
content:self.toViewSnapshot
isUp:up];
overlayer.contents = (id)self.fromViewSnapshot;
[overlayer addSublayer:frontLayer];
}
Swift 3+ answer based on Kekoa's solution:
let duration = 0.15 //match this to the value of the UIView.animate(withDuration:) call
CATransaction.begin()
CATransaction.setValue(duration, forKey: kCATransactionAnimationDuration)
myView.layer.mask.position = CGPoint(x: [new X], y: [new Y]) //just an example
CATransaction.commit()
Swift implementation of #stigi answer, my mask layer is called shape Layer
override var bounds: CGRect {
didSet {
// debugPrint(self.layer.animationKeys()) //Very useful for know if animation is happening and key name
let propertyAnimation = self.layer.animation(forKey: "bounds.size")
self.shapeLayer?.frame = self.layer.bounds
// if the bounds change happens within an animation, also animate the mask path
if let boundAnimation = propertyAnimation as? CABasicAnimation {
// copying the original animation allows us to keep all animation settings
if let basicAnimation = boundAnimation.copy() as? CABasicAnimation {
basicAnimation.keyPath = "path"
let newPath = UIBezierPathUtils.customShapePath(rect: self.layer.bounds, cornersTriangleSize: cornerTriangleSize).cgPath
basicAnimation.fromValue = self.shapeLayer?.path
basicAnimation.toValue = newPath
self.shapeLayer?.path = newPath
self.shapeLayer?.add(basicAnimation, forKey: "path")
}
} else {
self.shapeLayer?.path = UIBezierPathUtils.customShapePath(rect: self.layer.bounds, cornersTriangleSize: cornerTriangleSize).cgPath
}
}
}
I'm trying to scale an image down, change the image, then scale it back up.
CABasicAnimation* shrink = [CABasicAnimation animationWithKeyPath:#"transform.scale"];
shrink.toValue = [NSNumber numberWithDouble:0];
shrink.duration = 1;
shrink.delegate = self;
[myImageView.layer addAnimation:shrink forKey:#"shrink"];
makes the shrink, then when it completes, I change the image, and start the grow:
- (void)animationDidStop:(CAAnimation *)theAnimation finished:(BOOL)flag
{
myImageView.image = [images objectAtIndex:image];
CABasicAnimation* grow = [CABasicAnimation animationWithKeyPath:#"transform.scale"];
grow.toValue = CGAffineTransformMakeScale(1,1);
grow.delegate = self;
grow.duration = 1;
[myImageView.layer addAnimation:grow forKey:#"grow"];
}
This works great on the simulator, but on the device, when the shrink completes, I get a flash of the full-size, old image, then the grow animation begins with the new image.
Any idea how to get rid of that flash?
(I've tried "removedOnCompletion = NO;" and attempted setting the affineTransform equal to the scaled down size after the first completion, but didn't have much luck.)
Any tips appreciated.
kb
Edit:
Excellent! Setting the following:
shrink.fillMode = kCAFillModeForwards;
shrink.removedOnCompletion = NO;
Removed the flashing. Thanks, Ben!
Try setting your animation's fillMode to kCAFillModeForwards. That should leave the item as it was at the end of the animation, rather than before.
I've had the same problem when I tried to create another CAAnimation in the animationDidStop method. I suggest using CAKeyframeAnimation.