My project has several views that are subject to radial gravity at the center of their parent view, and elastic collisions so that they don't overlap. It works great, but sometimes I need to resize the views, and, when a view gets larger, the other views must move away from it so that all the views remain non-overlapping. I would expect the collision behavior to realize things are touching and to move them apart, but it doesn't seem to.
Here's what I'm trying now:
[UIView animateWithDuration:0.5 animations:^{
view.frame = CGRectInset(view.frame, -30, -30);
} completion:^(BOOL finished) {
[self.animator updateItemUsingCurrentState:view];
}];
The view grows just fine, the animation delegate is informed that the animation has resumed, but the other views don't move away. The newly enlarged view just overlaps (or underlaps depending on z order) the other views.
I tried changing the transform and not the frame - no dice. I tried removing the view from all the behaviors - no dice. I tried removing some and all of the behaviors from the animator - no dice. I tried calling updateItemUsingCurrentState: on all of the views - no dice. I need some dice!
Can you help? Thanks...(swift-ies, feel free to answer is swift. I'll translate it)
Thanks to this post, I learned that all behaviors that include the item being changed must be removed from the animator, then, after changing the view's properties, the behaviors should be added back to the animator.
I think that's crazy, but it worked.
[self.animator removeBehavior:self.behavior]; // for all behaviors that have view as an item
[UIView animateWithDuration:0.5 animations:^{
view.frame = CGRectInset(view.frame, -30, -30);
} completion:^(BOOL finished) {
[self.animator updateItemUsingCurrentState:view];
[self.animator removeBehavior:self.behavior];
}];
Related
I have a gesture which action moves a UIView to point B from point A. How can I add a nice transition of the UIView moving from point A to point B. I am looking at making it slowly move from point A to point B. How would I do this? At the moment to move the item I set the frame to point B.
check this code and set frame what you want
[UIView animateWithDuration:0.75 animations:^{
button.frame = CGRectMake(10, 70, 100, 100);
}];
If you're using auto-layout (and you almost certainly are - it's the default) then #PinkeshGjr s solution is likely to have problems. With AutoLayout you can't manipulate a view's frame directly. At some point after moving the frame the view's constraints can snatch it back.
Instead, you want to create constraints that control the property/properties that you want to animate (x and y position in this case) and control-drag from the constraints into your view controller's header to create outlets.
Then you want to change the constant value on the constraints and call layoutIfNeeded inside your animation code. Something like this:
buttonXConstraint.constant = 100;
buttonYConstraint.constant = 100;
[UIView animateWithDuration:0.75 animations:^{
[self.button layoutIfNeeded];
}];
The code above assumes that you've created 2 constraint outlets and called them buttonXConstraint and buttonYConstraint.
You can achieve that by using animateKeyframesWithDuration or animateWithDuration:animations but it will be just a linear interpolation. If you want to have more control over the animation I recommend that you take a look at MTAnimation it's really a powerful and easy to use Lib for achieving beautiful animations
Cheers
Very nice helper method to use for animating view.
- (void) animateView:(UIView *)view ToFrame:(CGRect) frame withDuration:(float) duration withDelay:(float) startDelay
{
[UIView animateWithDuration:duration delay:startDelay options:0 animations:^{
view.frame = frame;
} completion:^(BOOL finished)
{
// Completion actions
}];
}
I have UIScrollView subclass. Its content is reusable - about 4 or 5 views are used to display hundreds of elements (while scrolling hidden objects reused and jumps to another position when its needed to see them)
What i need: ability to automatically scroll my scroll view to any position. For example my scroll view displays 4th, 5th and 6th element and when I tap some button it needs to scroll to 30th element. In other words I need standard behaviour of UIScrollView.
This works fine:
[self setContentOffset:CGPointMake(index*elementWidth, 0) animated:YES];
but I need some customisation. For example, change animation duration, add some code to perform on end of animation.
Obvious decision:
[UIView animateWithDuration:3 delay:0 options:UIViewAnimationOptionBeginFromCurrentState animations:^{
[self setContentOffset:CGPointMake(index*elementWidth, 0)];
} completion:^(BOOL finished) {
//some code
}];
but I have some actions connected to scroll event, and so now all of them are in animation block and it causes all subview's frames to animate too (thanks to few reusable elements all of them animates not how i want)
The question is: How can I make custom animation (in fact I need custom duration, actions on end and BeginFromCurrentState option) for content offset WITHOUT animating all the code, connected to scrollViewDidScroll event?
UPD:
Thanks to Andrew's answer(first part) I solved issue with animation inside scrollViewDidScroll:
- (void)scrollViewDidScroll:(UIScrollView *)scrollView{
[UIView performWithoutAnimation:^{
[self refreshTiles];
}];
}
But scrollViewDidScroll must (for my purposes) executes every frame of animation like it was in case of
[self setContentOffset:CGPointMake(index*elementWidth, 0) animated:YES];
However, now it executes only once at start of animation.
How can I solve this?
Did you try the same approach, but with disabled animation in scrollViewDidScroll ?
On iOS 7, you could try wrapping your code in scrollViewDidScroll in
[UIView performWithoutAnimation:^{
//Your code here
}];
on previous iOS versions, you could try:
[CATransaction begin];
[CATransaction setDisableActions:YES];
//Your code here
[CATransaction commit];
Update:
Unfortunately that's where you hit the tough part of the whole thing. setContentOffset: calls the delegate just once, it's equivalent to setContentOffset:animated:NO, which again calls it just once.
setContentOffset:animated:YES calls the delegate as the animation changes the bounds of the scrollview and you want that, but you don't want the provided animation, so the only way around this that I can come up with is to gradually change the contentOffset of the scrollview, so that the animation system doesn't just jump to the final value, as is the case at the moment.
To do that you can look at keyframe animations, like so for iOS 7:
[UIView animateKeyframesWithDuration:duration delay:delay options:options animations:^{
[UIView addKeyframeWithRelativeStartTime:0.0 relativeDuration:0.5 animations:^{
[self setContentOffset:CGPointMake(floorf(index/2) * elementWidth, 0)];
}];
[UIView addKeyframeWithRelativeStartTime:0.5 relativeDuration:0.5 animations:^{
[self setContentOffset:CGPointMake(index*elementWidth, 0)];
}];
} completion:^(BOOL finished) {
//Completion Block
}];
This will get you two updates and of course you could use some math and a loop to add up a lot more of these with the appropriate timings.
On previous iOS versions, you'll have to drop to CoreAnimation for keyframe animations, but it's basically the same thing with a bit different syntax.
Method 2:
You can try polling the presentationLayer of the scrollview for any changes with a timer that you start at the beginning of the animation, since unfortunately the presentationLayer's properties aren't KVO observable. Or you can use needsDisplayForKey in a subclass of the layer to get notified when the bounds change, but that'll require some work to set up and it does cause redrawing, which might affect performance.
Method 3:
Would be to dissect exactly what happens to the scrollView when animated is YES try and intercept the animation that gets set on the scrollview and change its parameters, but since this would be the most hacky, breakable due to Apple's changes and trickiest method, I won't go into it.
A nice way to do this is with the AnimationEngine library. It's a very small library: six files, with three more if you want damped spring behavior.
Behind the scenes it uses a CADisplayLink to run your animation block once every frame. You get a clean block-based syntax that's easy to use, and a bunch of interpolation and easing functions that save you time.
To animate contentOffset:
startOffset = scrollView.contentOffset;
endOffset = ..
// Constant speed looks good...
const CGFloat kTimelineAnimationSpeed = 300;
CGFloat timelineAnimationDuration = fabs(deltaToDesiredX) / kTimelineAnimationSpeed;
[INTUAnimationEngine animateWithDuration:timelineAnimationDuration
delay:0
easing:INTULinear
animations:^(CGFloat progress) {
self.videoTimelineView.contentOffset =
INTUInterpolateCGPoint(startOffset, endOffset, progress);
}
completion:^(BOOL finished) {
autoscrollEnabled = YES;
}];
Try this:
UIView.animate(withDuration: 0.6, animations: {
self.view.collectionView.contentOffset = newOffset
self.view.layoutIfNeeded()
}, completion: nil)
I have two UIViews (My bad it is a UIView and a UIButton) which I am animating at the same time. I originally had a view and a containerView which would animate just fine and worked like a charm.
Now only one of my UIViews will move/animate in animateWithDuration even though through debugging the frame of the other view says that it is in a position it is not.
CGRect rect = self.toggle.frame;
CGRect tabRect = self.tabButton.frame;
rect.origin.x = rect.origin.x - rect.size.width;
NSLog(#"%f Before",tabRect.origin.x);
tabRect.origin.x = tabRect.origin.x - rect.size.width;
NSLog(#"%f After", tabRect.origin.x);
[UIView animateWithDuration:0.3 animations:^{ // animate the following:
self.toggle.frame = rect; // move to new location
self.tabButton.frame = tabRect;
}];
NSLog(#"%f AfterAnimation", tabButton.frame.origin.x);
The toggle view moves fine, but the tabButton view does not animate or move. The strange thing is that both the "After" and "AfterAnimation" debugging code returns the same value, which suggests the frame has indeed moved. Is there a specific reason that this will not work when toggle is a UIView when it would work as a UIContainerView?
Note that if I remove the line
self.toggle.frame = rect;
tabButton will animate correctly, but if I move toggle, tabButton will not move regardless of whether it is first in the animation block or second.
Edit: I have tried moving them into separate blocks and to change the center point rather than the frame, to no avail. It seems that if the toggle view moves, the tabButton will not move.
Edit 2: The pictorial evidence.{
In the following screenshots tabButton bg is green and toggle bg is red.
Above: Initial position (toggle is off-screen) correct position
Above: The problem in question toggle is correct tabButton is not
Above: When self.toggle.frame = rect is commented out (tabButton correct, toggle not)
}
Edit 3: It's even worse than I feared.{
I have done a few more tests and even if I take the toggle change out of the animation block to make it an instant thing, the tabButton will still not animate. This makes me think the tabButton may just fundamentally dislike the toggle view and/or myself so will not move just to spite me.
}
Edit 4:{
If I change the tabButton animation to tabButton.frame = CGRectMake(10,10,100,100) the View snaps instantly to that location and animates back to its original position in the same time as the animation duration.
}
I better add more bookkeeping/TLDR information in case things aren't clear.
toggle is an instance of ToggleDraw which is a subview of UIView which I created.
tabButton is a UIButton which is part of my IB viewController and a property of the class
Both toggle and tabButton are subviews of self.view
The animations will work individually with no modifications to the logic of the rects but will not work if they are animated at the same time
toggle animation seems to take precedence over tabButton animation regardless of the order
I had a problem with the animation of an UIView created in IB (the animation didn't start from the current position of the view, and ended in the initial position).
All worked fine after sending layoutIfNeeded() to the underlaying view before the animation block:
self.view.layoutIfNeeded()
UIView.animateWithDuration(0.5) { () -> Void in
...
I think it is not a problem about a UIView Animation. Maybe your toggle posiztion is related to your tabButton. For a try, your can set toggle frame to a rect lick (10, 10, 100,100), then check the result.
I've created an example of what you describe and everything seems to work fine. This is what I used:
UIView *toggle = [[UIView alloc] initWithFrame:CGRectMake(320, 64, 100, 100)];
[toggle setBackgroundColor:[UIColor redColor]];
[self.view addSubview:toggle];
UIButton *tabButton = [[UIButton alloc] initWithFrame:CGRectMake(220, 64, 100, 100)];
[tabButton setBackgroundColor:[UIColor greenColor]];
[self.view addSubview:tabButton];
CGRect rect = toggle.frame;
CGRect tabRect = tabButton.frame;
rect.origin.x = rect.origin.x - rect.size.width;
NSLog(#"%f Before",tabRect.origin.x);
tabRect.origin.x = tabRect.origin.x - rect.size.width;
NSLog(#"%f After", tabRect.origin.x);
[UIView animateWithDuration:1 animations:^{ // animate the following:
toggle.frame = rect; // move to new location
tabButton.frame = tabRect;
}];
What I can suggest is to make sure that the code is being ran on mainthread:
dispatch_async(dispatch_get_main_queue(), ^{
[UIView animateWithDuration:0.3 animations:^{
self.toggle.frame = rect; // move to new location
self.tabButton.frame = tabRect;
}];
});
Also take into account that the log you have after the animation code is incorrect as it won't run after the animation, but rather right next to asking for the animation.
If you want code to run after the animation you should use:
[UIView animateWithDuration:0.3 animations:^{
self.toggle.frame = rect; // move to new location
self.tabButton.frame = tabRect;
} completion:^(BOOL finished){
NSLog(#"Finished animating!");
}];
I have found a solution to the problem. If I initialise the UIButton (tabButton) programmatically rather than through the interface builder, both views will animate simultaneously.
This however seems very hacky to me, kind of like putting a bandaid over a missing foot and hoping it will sort itself out.
I could not work out the root cause of the problem but at least I could avoid the symptoms.
If anyone knows why the views would not animate when the button was made in the interface builder post an answer here, I am interested in knowing the reason behind this.
Thanks for your help everyone.
I've been searching around SO and have found some related posts, but none that have (yet) solved my problem.
I have a view setup in my storyboard, with a constraint hooked up through an IBOulet. Upon a certain action, the view should move up (or down to it's initial position). For the life of me, I cannot get it to work properly. Prior to autolayout, I ran this bit of code:
- (void)animateStarBackground:(NSString *)animationID
finished:(NSNumber *)finished
context:(void *)context
myView:(UIView *)myView
xPos:(float)xPos
yPos:(float)yPos {
[UIView beginAnimations:nil context:nil];
[UIView setAnimationDuration:0.2];
[UIView setAnimationDelay:0.5];
[UIView setAnimationCurve:UIViewAnimationCurveEaseInOut];
[UIView setAnimationDelegate:self];
myView.center = CGPointMake(xPos, yPos);
[UIView commitAnimations];
}
It used to work great, but anyway... we all know that this doesn't work in Autolayout anymore. So I changed it to the following:
-(void)animateButton:(UIView *)myView {
[UIView animateWithDuration:8.0f animations:^{
_viewConstA.constant = 45.0;
[myView layoutIfNeeded];
}];
}
When the action occurs, instead of starting in it's initial position as set in the Storyboard, it starts off as a 1x1 pixel view in the top left hand corner and animates downward into it's final resting place (instead of moving up 15 pixels as I had intended it to).
Now, if I take out the [myView layoutIfNeeded]; portion, the action positions the view in exactly the right place... BUT it doesn't animate there. It's just instantly there as the view appears.
The first screen grab is the initial location.
2nd grab is what's supposed to be the views final resting place.
3rd is the view animating from the wrong spot and direction.
Thoughts / comments? What the heck am I doing wrong? I thought this would be so easy... I've got to be missing something obvious.
When I call the following block-based animation from viewDidLoad, it animates the frame from CGRectZero to the final location. But if I call this from viewDidAppear, it works just as expected.
- (void)animateMovementByConstraint
{
[UIView animateWithDuration:0.5
animations:^{
self.topLayoutConstraint.constant = 100;
[self.view layoutIfNeeded];
}];
}
(In this example, topLayoutConstraint is an IBOutlet that I defined in Interface Builder for the top vertical constraint on the control that I wanted to animate.)
With auto layout, since I've started initiating my animations in viewDidAppear, I haven't had any problems.
I use a UIView animation to randomly animate 5 squares (UIButtons) around the screen. Depending on a user selection, there are anywhere from 2 to 5 squares visible. When only 2 are visible, the other three's hidden values get set to YES, so they are actually still animating (right?), they just aren't visible. But when only 2 are visible, the animation is smooth, but when all five are visible, the animation gets choppy. I'm not really sure how to describe it, because the squares are still moving at the correct speed and moving to the correct points; the choppiness isn't terrible, just bad enough to be noticeable. Is there any way to get rid of it? This is the code I use to animate the squares:
Edit: changed animations to block:
[UIView animateWithDuration:animationSpeed
delay:0
options:UIViewAnimationOptionCurveLinear
animations:^{
view.center = destPoint;
}
completion:^(BOOL finished){
if([view isEqual:squareThree])
[self moveBadGuys];
}
];
/*for(UIButton* button in squareArray) {
if(!shouldMove)
return;
[UIView beginAnimations:#"b" context:nil];
[UIView setAnimationDuration:animationSpeed];
[UIView setAnimationCurve:UIViewAnimationCurveEaseOut];
view.center = destPoint;
[UIView commitAnimations];
}*/
Edit: the view presenting this is the third in a stack of three UIViewController presented with
ViewController* controller = [[[ViewController alloc] init] autorelease];
[self presentModalViewController:controller animated:NO];
Does this way of presenting views eat up memory?
There are a few things that can cause this. It always comes down to how complex the content is. Also, simulator can be really bad about handling animation, so be sure you are testing on real hardware.
Are there large images on the buttons? Are the buttons casting shadows? Those things can slow it down.
Also- use block based animation. Not the old begin-commit methods.
Not exactly sure why it's slow, but have you tried nesting the thing differently?
if(!shouldMove)
return;
[UIView beginAnimations:#"b" context:nil];
[UIView setAnimationDuration:animationSpeed];
[UIView setAnimationCurve:UIViewAnimationCurveEaseOut];
for(UIButton* button in squareArray) {
view.center = destPoint;
}
[UIView commitAnimations];
does (almost - the logic is a bit different in the !shouldMove case, but that's a different story) the same, but in a cleaner way.