Animation shows unwanted shadow - ios

I'm animating an image to move up 50px, but as it moves, it leaves a shadow. How do I remove this shadow? I'd like the image to move smoothly. The shadow is only really present at the beginning of the animation.
Method used:
- (void)moveImage:(UIImageView *)image duration:(NSTimeInterval)duration
curve:(int)curve x:(CGFloat)x y:(CGFloat)y
{
// Setup the animation
[UIView beginAnimations:nil context:NULL];
[UIView setAnimationDuration:duration];
[UIView setAnimationCurve:curve];
[UIView setAnimationBeginsFromCurrentState:YES];
// The transform matrix
CGAffineTransform transform = CGAffineTransformMakeTranslation(x, y);
image.transform = transform;
// Commit the changes
[UIView commitAnimations];
}
Calling the method:
[self moveImage:imageToMove duration:1.0
curve:UIViewAnimationCurveLinear x:0.0 y:-70.0];
Image:

Related

Resize an image but never came back to original size

I'm trying to resize an image (tiny and return to original size). This code is working for resize the image but never go back to the original size. I thin I miss something in the endItem1Animation code. Any suggestions? Thanks
if (CGRectIntersectsRect(image.frame, item1.frame)) {
item1.hidden = YES;
// Item 1 Animation (Go Tiny)
[UIView beginAnimations:NULL context:NULL];
[UIView setAnimationsEnabled:YES];
[UIView setAnimationDelay:0];
[UIView setAnimationDuration:0];
[UIView setAnimationRepeatCount:0];
[UIView setAnimationBeginsFromCurrentState:YES];
[UIView setAnimationRepeatAutoreverses:NO];
CGRect newRect = image.frame;
newRect.size = CGSizeMake(25,25);
image.frame = newRect;
[UIView commitAnimations];
[self endItem1Animation];
This is the endItem1Animation code:
// Item 1 End Animation (Return to Original Size)
[UIView beginAnimations:NULL context:NULL];
[UIView setAnimationsEnabled:YES];
[UIView setAnimationDelay:0];
[UIView setAnimationDuration:5.0];
[UIView setAnimationRepeatCount:0];
[UIView setAnimationBeginsFromCurrentState:YES];
[UIView setAnimationRepeatAutoreverses:NO];
CGRect newRect = image.frame;
newRect.size = CGSizeMake(50,50);
image.frame = newRect;
[UIView commitAnimations];
The problem is that when you call beginAnimations / endAnimation, this does not block the main thread from running, so calling [self endItem1Animation] sets the second animation which will prevent the first animation from running.
You'll want to use the UIView animation block method instead, which lets you supply a completion handler when the animation completes.
[UIView animateWithDuration:0.5 animations:^{
CGRect newRect = image.frame;
newRect.size = CGSizeMake(25,25);
image.frame = newRect;
} completion:^(BOOL finished) {
[self endItem1Animation];
}];
Another, more straightforward issue, is that the duration for the first animation is zero.
I fix this issue running a selector at the end of the code. Now my code is working. Here is my final code, I Hope to help someone. Thank you for your suggestions.
if (CGRectIntersectsRect(image.frame, item1.frame)) {
item1.hidden = YES;
// Item 1 Animation (Go Tiny)
[UIView beginAnimations:NULL context:NULL];
[UIView setAnimationsEnabled:YES];
[UIView setAnimationDelay:0];
[UIView setAnimationDuration:0];
[UIView setAnimationRepeatCount:0];
[UIView setAnimationBeginsFromCurrentState:YES];
[UIView setAnimationRepeatAutoreverses:NO];
CGRect newRect = image.frame;
newRect.size = CGSizeMake(25,25);
image.frame = newRect;
[UIView commitAnimations];
[self performSelector:#selector(endItem1Animation) withObject:nil afterDelay:8.0];

animateWithDuration:delay:options:animations:completion: not working (strangely)

I'm trying to translate a UIView for a distance using the following code:
CGAffineTransform transform = CGAffineTransformMakeTranslation(-100, -100);
[self.exposureHintView setTransform:transform];
[UIView animateWithDuration:2.0
delay:0.0
options:UIViewAnimationOptionBeginFromCurrentState
animations:^{
NSLog(#"Begin!");
CGAffineTransform newTrans = CGAffineTransformMakeTranslation(0, 0);
[self.exposureHintView setTransform:newTrans];
}
completion:^(BOOL finished) {
NSLog(#"End %d", finished);
}];
So basically, I'm justing trying to move the view from some point say (-100, -100) to where it should be (0, 0) relative to itself.
Since I wanted to animate it once the view appeared, so I put the code in viewDidAppear:. But when I run the code, nothing happened.
The self.exposureHintView here is a custom subclass of UIView, does it matter?
Why?
[UIView beginAnimations:nil context:NULL];
[UIView setAnimationDuration:0.5];
[_AboutView setFrame:CGRectMake(0, 0, 320, 510)];
[UIView commitAnimations];
Use this code to change the position of your view
I think the problem here is you are create exposureHintView in storyboard or XIB file without code programmatically.
Try to do as the follows:
- (void)viewDidLoad
{
//Init exposureHintView
UIView* exposureHintView = [[UIView alloc]initWithFrame(sampleFrame)];
[self addSubView: exposureHintView];
//Set transform
CGAffineTransform transform = CGAffineTransformMakeTranslation(-100, -100);
[self.exposureHintView setTransform:transform];
//Commit animation
[UIView animateWithDuration:2.0 delay:0.0
options:UIViewAnimationOptionBeginFromCurrentState
animations:^{
NSLog(#"Begin!");
CGAffineTransform newTrans = CGAffineTransformMakeTranslation(0, 0);
[self.exposureHintView setTransform:newTrans];
}
completion:^(BOOL finished) {
NSLog(#"End %d", finished);
}];
The reason here is your could not set Frame or Transform or some another attribute of this UIView in >>ViewDidLoad when you using storyboard or XIB

Image is jumping before animating

I currently have an image animating on the click of a button, but the problem is that the image is jumping from it's position on the storyboard before it starts the animation. I cannot figure out why it's doing this - all I would like to do it move it from its current position off the screen to the right.
Am I doing something wrong, or just missing something?
Original position:
Beginning of animation:
moveImage trigger:
[self moveImage:_cornerCloud duration:3.0
curve:UIViewAnimationOptionCurveLinear x:200.0 y:0];
moveImage function:
- (void)moveImage:(UIImageView *)image duration:(NSTimeInterval)duration
curve:(int)curve x:(CGFloat)x y:(CGFloat)y
{
// Setup the animation
[UIView beginAnimations:nil context:NULL];
[UIView setAnimationDuration:duration];
[UIView setAnimationCurve:curve];
[UIView setAnimationBeginsFromCurrentState:YES];
// The transform matrix
CGAffineTransform transform = CGAffineTransformMakeTranslation(x, y);
image.transform = transform;
// Commit the changes
[UIView commitAnimations];
}
[UIView animateWithDuration:3.0f
delay:0.0f
options:UIViewAnimationOptionCurveLinear
animations:^{
// just set the center to off-screen
}
completion:^(BOOL finished){}];
That should be a bit easier.

Trying to animate one UIImageView with two animations, only one animation has duration

What I want to do is flip this UIImageView in an instant, no animation, then I need it to float to it's intended position on the screen. Both of the transformations are working, but not the way I want them to.
[UIView beginAnimations:nil context:NULL];
[UIView setAnimationDuration:0.5];
resultsEnemy.transform = CGAffineTransformMakeTranslation(0, 0);
[UIView commitAnimations];
resultsEnemy.transform = CGAffineTransformMakeScale(-1, 1);
This is the code I am using. Despite the fact that the scale code (which I am using to flip the UIImageView) is not part of the animation with the 0.5 duration, it is following those rules. How do I avoid this?
Applying two transforms like that isn't going to produce the result you expect. What you need to do is combine them into a single transform matrix. The following should work as expected.
[UIView beginAnimations:nil context:NULL];
[UIView setAnimationDuration:0.5];
// Create two separate transforms and concatenate them together.
// Use that new transform matrix to accomplish both transforms at once.
CGAffineTransform translate = CGAffineTransformMakeTranslation(0, 0);
CGAffineTransform scale = CGAffineTransformMakeScale(-1, 1);
resultsEnemy.transform = CGAffineTransformConcat(translate, scale);
[UIView commitAnimations];
Edit: Based off of your clarification, you seem to be wanting something like this:
CGAffineTransform scale = CGAffineTransformMakeScale(-1, 1);
CGAffineTransform translate = CGAffineTransformMakeTranslation(0, 0);
[CATransaction begin];
[CATransaction setValue:(id)kCFBooleanTrue forKey:kCATransactionDisableActions];
resultsEnemy.transform = scale;
[CATransaction commit];
[UIView beginAnimations:nil context:NULL];
[UIView setAnimationDuration:0.5];
resultsEnemy.transform = CGAffineTransformConcat(translate, scale);
[UIView commitAnimations];

how can I interrupt/stop animation when I rotate?

For example, I use the animation in landscape status, duration is 5.0s, from status A to B; in the middle of the 5.0s, I may rotate the iPad from landscape to portrait. I want the animation stopped and make the UI status to C after I rotated.
I'm not sure my question is clear.
How can I do that?
my animation code:
- (void)moveImage:(UIImageView *)image duration:(NSTimeInterval)duration x:(NSNumber*)dx y:(NSNumber*)dy
{
// Setup the animation
[UIView beginAnimations:nil context:NULL];
[UIView setAnimationDuration:duration];
[UIView setAnimationCurve:UIViewAnimationCurveEaseInOut];
[UIView setAnimationBeginsFromCurrentState:YES];
// The transform matrix
float fx = [dx floatValue];
float fy = [dy floatValue];
CGAffineTransform transform = CGAffineTransformMakeTranslation(fx, fy);
//CGAffineTransform transform = CGAffineTransformMakeRotation(0.4);
//CGAffineTransform transform = CGAffineTransformMakeScale(2.0, 2.0);
image.transform = transform;
// Commit the changes
[UIView commitAnimations];
}
Starting and Stopping Explicit Animations has a section on starting and stopping core animations
willRotateToInterfaceOrientation:duration notifies you when the rotation begins.
So all have to do is 1) from 2)

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