How to slide and rotate UIImageView animated - ios

I want to make an animation that moves an UIImageView to another location on the screen of the device and simultaneously rotates the view.
I tried using UIView methods like transitionWithView and animateWithDuration and they work most of the time but not every time.
Randomly the animation seems to run so that the animation does not start from the current position but instead the UIImageView slides to its position from somewhere outside the screen. The ending point is correct and if I set the view transform without animation the end result is correct. So, it just looks like every now and then the starting transform for the animation is messed up.
I'm trying to work around this glitch by resetting the view transform before the animation with CGAffineTransformIdentity but even then I'm randomly seeing the view slide in from outside the screen. I tested this also on device and the same issue exists.
Here is the simplified code for the case. I'm reseting the transform to a fixed point on screen. Then I create a transform with a little slide up and rotation and in the animation I set this transform to the image view. The wait flag with run loop is there to make sure the execution does not continue from this call before the animation is finished.
-(void) foldAnimation:(int)player {
// reset view transform
UIImageView *leftCard = (UIImageView*)[self.view viewWithTag:6];
leftCard.transform = CGAffineTransformTranslate(CGAffineTransformIdentity, 120.0, 408.0);
// slide and rotate
float ySlide = -80.0 + arc4random_uniform(5);
CGAffineTransform transform1 = CGAffineTransformTranslate(leftCard.transform, 0.0, ySlide);
transform1 = CGAffineTransformRotate(transform1, M_PI/180*(arc4random_uniform(7)-2));
waitFlag = YES;
[UIView transitionWithView:leftCard
duration:0.4
options:UIViewAnimationOptionCurveEaseIn
animations:^{
leftCard.transform = transform1;
}
completion:^(BOOL finished){
waitFlag = NO;
}];
NSRunLoop *theRL = [NSRunLoop currentRunLoop];
while (waitFlag && [theRL runMode:NSDefaultRunLoopMode beforeDate:[NSDate distantFuture]]);
}

Related

box flip 3D animation for side menu

I have scrollview and inside scrollview I have 2 views as MainView and another as SideMenuView.
What I want to make animation like below.
Any idea what needs to be done to get this working?
Psuedo Code below:
- (void)animateSideMenu{
homeView.frame = CGRectMake(sideMenuWidth, 0.0, (self.view.frame.size.width - sideMenuWidth), self.view.frame.size.height);
[UIView animateWithDuration:1.0 delay:0.0
options:UIViewAnimationOptionCurveLinear
animations:^{
sideMenu.frame = CGRectMake(0.0, 0.0, sideMenuWidth, sideMenuHeight);
[self flipAnimation];
} completion:^(BOOL finished) {
}];
}
- (void)flipAnimation{
CABasicAnimation *yRotate = [CABasicAnimation animationWithKeyPath:#"transform.rotation.y"];
yRotate.fromValue = [NSValue valueWithCATransform3D:CATransform3DMakeRotation(M_PI_2, 0, 1, 0)];
yRotate.toValue = #(M_PI * 1.5);
yRotate.duration = 0.5;
yRotate.timingFunction = [CAMediaTimingFunction functionWithName:kCAMediaTimingFunctionLinear];
[sideMenu.layer addAnimation:yRotate forKey:#"yRotate"];
}
Below are the steps to develop this type of animation:
set the frame of homeView(Red colour view) of screen size & add pan gesture to this view.
set frame of sideMenu view in negative x-axis.
Create a responder function for pan gesture recogniser, in this function call the above mentioned animateSideMenu function.
Adjust the animation parameters accordingly.
Try with this & let me know if anything comes up.
I would not use a scrollview but rather a UIPanGestureRecognizer in which I would detect your current "pan offset" and calculate a current fraction of the animation and positions of those two views (let's simplify it so that the menu is view1 and the rest view2).
Then I would simply set an appropriate transform in the .Changed state.
In .Ended state I would see whether the menu is closer to being open or close and create an animation with .toValue set accordingly. You should use CAAnimations or better - Facebook pop animations because you can pause and remove them and the views stay put and not jump to their initial positions (as is often the case with UIViewAnimate).
If you need help with writing exact code you can write here and I'll edit my answer.
There's tutorial for exactly that menu, though it's in Swift:
https://www.raywenderlich.com/87268/3d-effect-taasky-swift

UIView animation with CGAffineTransformMakeScale changes size instantly with decimal number

- (void)startAnimation {
//reverse - shrinking from full size
if (_reversed == YES) {
//self.transform = CGAffineTransformMakeScale(1.0, 1.0);
[UIView animateWithDuration:1.0f delay:0.0f options:UIViewAnimationOptionCurveLinear animations:^{
self.transform = CGAffineTransformMakeScale(0.1, 0.1); //this line does it instantly
self.alpha = 0;
} completion:^(BOOL finished) {
[self removeFromSuperview];
}];
} else {
//non reverse - expanding from middle
self.transform = CGAffineTransformMakeScale(0.001, 0.001);
[UIView animateWithDuration:1.0f delay:0.0f options:UIViewAnimationOptionCurveLinear animations:^{
self.transform = CGAffineTransformMakeScale(1.0, 1.0);
self.alpha = 0;
} completion:^(BOOL finished) {
[self removeFromSuperview];
}];
}
}
The non reverse piece of code does work fine as I expect, however when I do the _reversed == YES bit, the transformation inside the animation block happens instantly. If I comment that line of code, then the view stays the right size, but if i uncomment it then it shrinks instantly but the alpha still does the fade animation. Why does this happen?
Edit: I figured out what happened but I don't know how to fix it. The view does do the animation, only the size of the view changes instantly but it still 'slides' into the centre as if it is shrinking (what you see is just a small rectangle sliding to the middle as if it's the top left corner of the object). If I scale the view to 2 first, then scale down to 1 the animation works fine, its only when going from 1 to a decimal number that it doesn't work. Also I used draw rect to create an object with core graphics and the transform problem affects that, but not the actual frame if a set background colour.
I was running into a similar issue, where the position of the view would suddenly jump before animating in a change of transform with CGAffineTransformMakeScale. I noticed that the size of the "jump" seemed to be proportional to the scaling that would occur later in the animation.
I could fix this problem by finding that in a viewWillLayoutSubviews() override, I was setting the frame of the view being animated. As a rule, don't set the frames of views that will have a non-identity transform. So in the viewWillLayoutSubviews() override, I set the view's bounds and layer.position instead and now the animation is smooth as silk.

How to stop and reverse a UIView animation?

I have animated a UIView so that it shrinks when the user touches a toggle button and it expands back to its original size when the user touches the button again. So far everything works just fine. The problem is that the animation takes some time - e.g. 3 seconds. During that time I still want the user to be able to interact with the interface. So when the user touches the button again while the animation is still in progress the animation is supposed to stop right where it is and reverse.
In the Apple Q&As I have found a way to pause all animations immediately:
https://developer.apple.com/library/ios/#qa/qa2009/qa1673.html
But I do not see a way to reverse the animation from here (and omit the rest of the initial animation). How do I accomplish this?
- (IBAction)toggleMeter:(id)sender {
if (self.myView.hidden) {
self.myView.hidden = NO;
[UIView animateWithDuration:3 animations:^{
self.myView.transform = expandMatrix;
} completion:nil];
} else {
[UIView animateWithDuration:3 animations:^{
self.myView.transform = shrinkMatrix;
} completion:^(BOOL finished) {
self.myView.hidden = YES;
}];
}
}
In addition to the below (in which we grab the current state from the presentation layer, stop the animation, reset the current state from the saved presentation layer, and initiate the new animation), there is a much easier solution.
If doing block-based animations, if you want to stop an animation and launch a new animation in iOS versions prior to 8.0, you can simply use the UIViewAnimationOptionBeginFromCurrentState option. (Effective in iOS 8, the default behavior is to not only start from the current state, but to do so in a manner that reflects both the current location as well as the current velocity, rendering it largely unnecessary to worry about this issue at all. See WWDC 2014 video Building Interruptible and Responsive Interactions for more information.)
[UIView animateWithDuration:3.0
delay:0.0
options:UIViewAnimationOptionBeginFromCurrentState | UIViewAnimationOptionAllowUserInteraction
animations:^{
// specify the new `frame`, `transform`, etc. here
}
completion:NULL];
You can achieve this by stopping the current animation and starting the new animation from where the current one left off. You can do this with Quartz 2D:
Add QuartzCore.framework to your project if you haven't already. (In contemporary versions of Xcode, it is often unnecessary to explicitly do this as it is automatically linked to the project.)
Import the necessary header if you haven't already (again, not needed in contemporary versions of Xcode):
#import <QuartzCore/QuartzCore.h>
Have your code stop the existing animation:
[self.subview.layer removeAllAnimations];
Get a reference to the current presentation layer (i.e. the state of the view as it is precisely at this moment):
CALayer *currentLayer = self.subview.layer.presentationLayer;
Reset the transform (or frame or whatever) according to the current value in the presentationLayer:
self.subview.layer.transform = currentLayer.transform;
Now animate from that transform (or frame or whatever) to the new value:
[UIView animateWithDuration:1.0
delay:0.0
options:UIViewAnimationOptionAllowUserInteraction
animations:^{
self.subview.layer.transform = newTransform;
}
completion:NULL];
Putting that all together, here is a routine that toggles my transform scale from 2.0x to identify and back:
- (IBAction)didTouchUpInsideAnimateButton:(id)sender
{
CALayer *currentLayer = self.subview.layer.presentationLayer;
[self.subview.layer removeAllAnimations];
self.subview.layer.transform = currentLayer.transform;
CATransform3D newTransform;
self.large = !self.large;
if (self.large)
newTransform = CATransform3DMakeScale(2.0, 2.0, 1.0);
else
newTransform = CATransform3DIdentity;
[UIView animateWithDuration:1.0
delay:0.0
options:UIViewAnimationOptionAllowUserInteraction
animations:^{
self.subview.layer.transform = newTransform;
}
completion:NULL];
}
Or if you wanted to toggle frame sizes from 100x100 to 200x200 and back:
- (IBAction)didTouchUpInsideAnimateButton:(id)sender
{
CALayer *currentLayer = self.subview.layer.presentationLayer;
[self.subview.layer removeAllAnimations];
CGRect newFrame = currentLayer.frame;
self.subview.frame = currentLayer.frame;
self.large = !self.large;
if (self.large)
newFrame.size = CGSizeMake(200.0, 200.0);
else
newFrame.size = CGSizeMake(100.0, 100.0);
[UIView animateWithDuration:1.0
delay:0.0
options:UIViewAnimationOptionAllowUserInteraction
animations:^{
self.subview.frame = newFrame;
}
completion:NULL];
}
By the way, while it generally doesn't really matter for really quick animations, for slow animations like yours, you might want to set the duration of the reversing animation to be the same as how far you've progressed in your current animation (e.g., if you're 0.5 seconds into a 3.0 second animation, when you reverse, you probably don't want to take 3.0 seconds to reverse that small portion of the animation that you have done so far, but rather just 0.5 seconds). Thus, that might look like:
- (IBAction)didTouchUpInsideAnimateButton:(id)sender
{
CFTimeInterval duration = kAnimationDuration; // default the duration to some constant
CFTimeInterval currentMediaTime = CACurrentMediaTime(); // get the current media time
static CFTimeInterval lastAnimationStart = 0.0; // media time of last animation (zero the first time)
// if we previously animated, then calculate how far along in the previous animation we were
// and we'll use that for the duration of the reversing animation; if larger than
// kAnimationDuration that means the prior animation was done, so we'll just use
// kAnimationDuration for the length of this animation
if (lastAnimationStart)
duration = MIN(kAnimationDuration, (currentMediaTime - lastAnimationStart));
// save our media time for future reference (i.e. future invocations of this routine)
lastAnimationStart = currentMediaTime;
// if you want the animations to stay relative the same speed if reversing an ongoing
// reversal, you can backdate the lastAnimationStart to what the lastAnimationStart
// would have been if it was a full animation; if you don't do this, if you repeatedly
// reverse a reversal that is still in progress, they'll incrementally speed up.
if (duration < kAnimationDuration)
lastAnimationStart -= (kAnimationDuration - duration);
// grab the state of the layer as it is right now
CALayer *currentLayer = self.subview.layer.presentationLayer;
// cancel any animations in progress
[self.subview.layer removeAllAnimations];
// set the transform to be as it is now, possibly in the middle of an animation
self.subview.layer.transform = currentLayer.transform;
// toggle our flag as to whether we're looking at large view or not
self.large = !self.large;
// set the transform based upon the state of the `large` boolean
CATransform3D newTransform;
if (self.large)
newTransform = CATransform3DMakeScale(2.0, 2.0, 1.0);
else
newTransform = CATransform3DIdentity;
// now animate to our new setting
[UIView animateWithDuration:duration
delay:0.0
options:UIViewAnimationOptionAllowUserInteraction
animations:^{
self.subview.layer.transform = newTransform;
}
completion:NULL];
}
There is a common trick you can use to do this, but it is necessary to write a separate method to shrink (and another similar one to expand):
- (void) shrink {
[UIView animateWithDuration:0.3
animations:^{
self.myView.transform = shrinkALittleBitMatrix;
}
completion:^(BOOL finished){
if (continueShrinking && size>0) {
size=size-1;
[self shrink];
}
}];
}
So now, the trick is to break the 3 seconds animation of shrinking into 10 animations (or more than 10, of course) of 0.3 sec each in which you shrink 1/10th of the whole animation: shrinkALittleBitMatrix. After each animation is finished you call the same method only when the bool ivar continueShrinking is true and when the int ivar size is positive (the view in full size would be size=10 and the view with minimum size would be size=0). When you press the button you change the ivar continueShrinking to FALSE, and then call expand. This will stop the animation in less than 0.3 seconds.
Well, you have to fill the details but I hope it helps.
First: how to remove or cancel a animation with view?
[view.layer removeAllAnimations]
if the view have many animations, such as, one animation is move from top to bottom, other is move from left to right;
you can cancel or remove a special animation like this:
[view.layer removeAnimationForKey:#"someKey"];
// the key is you assign when you create a animation
CABasicAnimation *anim = [CABasicAnimation animationWithKeyPath:#"someKey"];
when you do that, animation will stop, it will invoke it's delegate:
- (void)animationDidStop:(CAAnimation *)anim finished:(BOOL)flag
if flag == 1, indicate animation is completed.
if flag == 0, indicate animation is not completed, it maybe cancelled、removed.
Second: so , you can do what you want to do in this delegate method.
if you want get the view's frame when the remove code excute, you can do this:
currentFrame = view.layer.presentationlayer.frame;
Note:
when you get the current frame and remove animation , the view will also animate a period time, so currentFrame is not the last frame in the device screen.
I cann't resolve this question at now. if some day I can, I will update this question.

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.

Issue rotating a UIView object using Core Animation and blocks

I have a problem with a UIView-subclass object that I am rotating using Core Animation in response to a UISwipeGesture.
To describe the context: I have a round dial that I have drawn in CG and added to the main view as a subview.
In response to swipe gestures I am instructing it to rotate 15 degrees in either direction dependent on whether it;s a left or right swipe.
The problem that it will only rotate each way once. Subsequent gestures are recognised (evident from other actions that are triggered) but the animation does not repeat. I can go left once then right once. But trying to go in either direction multiple times doesn't work. Here's the relevant code, let me know your thoughts...
- (IBAction)handleLeftSwipe:(UISwipeGestureRecognizer *)sender
{
if ([control1 pointInside:[sender locationInView:control1] withEvent:nil])
{
//updates the display value
testDisplay.displayValue = testDisplay.displayValue + 0.1;
[testDisplay setNeedsDisplay];
//rotates the dial
[UIView animateWithDuration:0.25 animations:^{
CGAffineTransform xform = CGAffineTransformMakeRotation(radians(+15));
control1.transform = xform;
[control1 setNeedsDisplay];
}];
}
CGAffineTransform xform = CGAffineTransformMakeRotation(radians(+15));
Do you keep a total of how far the rotation is. CGAffineTransformMakeRotation are not additive. Only the most recent is used. So you are setting it to 15 each time, not 15 more each time.
Here's a super simple example of rotating a view cumulatively. This rotates the view by 180 degrees each button press.
- (IBAction) onRotateMyView: (id) sender
{
[UIView animateWithDuration:0.3 animations:^{
myView.transform = CGAffineTransformMakeRotation(M_PI/2*rotationCounter);
} completion:^(BOOL finished){
//No nothing
}];
++rotationCounter;
}

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