I'm trying to do a cross dissolve on three UILabels (display1, display2, display3), by using a block animation to fade out, change text and then fade them in one at a time. The code I'm using is:
[UIView animateWithDuration:1.0 delay: 1.0
animations:^{
display1.alpha = 0.0;
display2.alpha = 0.0;
display3.alpha = 0.0;
}
completion:^{
[display1 setText:[NSString stringWithFormat:#"%#",[engine getstring]]];
[display2 setText:[NSString stringWithFormat:#"%#",[engine getstring]]];
[display3 setText:[NSString stringWithFormat:#"%#",[engine getstring]]];
[UIView animateWithDuration:1.0 delay:1.0
animations:^{
display1.alpha = 1.0;
[UIView animateWithDuration:1.0 delay:1.0
animations:^{
display2.alpha = 1.0;
[UIView animateWithDuration:1.0
delay:1.0
animations:^{
display3.alpha = 1.0;
} completion:nil];
} completion:nil];
} completion:nil];
}];
I get the following warnings:
Method '+animateWithDuration:delay:animations:completion:' not found*
and
'UIView' may not respond to method '+animateWithDuration:delay:animations:completion:'
I'm using Xcode 4.0 with an iOS Build Target of 4.3.
You want to use
+ animateWithDuration:delay:options:animations:completion:
instead. Note the options: in the middle.
Related
I am attempting to make my item "glow" every 3 seconds changing its alpha from a high to low value and back. It however "flickers" and basically changes every 0.2 seconds from color to color randomly. I have pasted the method below. Its probably something to do with when completion is called but not sure?
-(void)showLoading{
[self.postTableView setHidden:YES];
self.isLoading = true;
//Disappear
[UIView animateWithDuration:1.5 animations:^(void) {
self.loadingLabel.alpha = 0.8;
self.loadingLabel.alpha = 0.3;
}
completion:^(BOOL finished){
//Appear
[UIView animateWithDuration:1.5 animations:^(void) {
self.loadingLabel.alpha = 0.3;
self.loadingLabel.alpha = 0.8;
}completion:^(BOOL finished2){
if(true){
[self showLoading];
}
}];
}]; }
self.loadingLabel.alpha = .8;
[UIView animateWithDuration:1.5 delay:0 options:UIViewAnimationOptionAutoreverse | UIViewAnimationOptionRepeat animations:^{
self.loadingLabel.alpha = .3;
} completion:nil];
UIViewAnimationOptionAutoreverse & UIViewAnimationOptionRepeat can help you.
you can stop it by
self.loadingLabel.alpha = .8;
or the other animation.
[UIView animateWithDuration:1.5 delay:0 options:UIViewAnimationOptionBeginFromCurrentState animations:^{
self.loadingLabel.alpha = .8;
} completion:nil];
UIViewAnimationOptionBeginFromCurrentState is a useful option for you to stop your animation by the other animation.
-(void)viewDidLoad{
//use schedule timer to call repeatedly showLoading method until loading done
}
-(void)showLoading{
[self.postTableView setHidden:YES];
self.isLoading = true;
[UIView beginAnimations:nil context:nil];
[UIView setAnimationDuration:1.5];
[UIView setAnimationCurve:UIViewAnimationCurveEaseIn];
self.loadingLabel.alpha = 0.3;
[UIView commitAnimations];
[UIView beginAnimations:nil context:nil];
[UIView setAnimationDuration:1.5];
[UIView setAnimationCurve:UIViewAnimationCurveEaseIn];
self.loadingLabel.alpha = 0.8;
[UIView commitAnimations];
}
I want to animate the text of a UILabel so that it shows one text for a couple of seconds and after that fades into a default text.
I'm currently using the following code:
-(void)tapOnBalance:(id)sender{
[UIView animateWithDuration:1.0 delay:0.0 options:UIViewAnimationOptionTransitionCrossDissolve animations:^{
cell.amountLabel.text = #"Hola!";
} completion:nil];
// Pause the function - act as a 'delay'
[[NSRunLoop currentRunLoop] runUntilDate:[NSDate dateWithTimeIntervalSinceNow:3]];
[UIView animateWithDuration:1.0 delay:0.0 options:UIViewAnimationOptionTransitionCrossDissolve animations:^{
cell.amountLabel.text = #"Hallo!";
} completion:nil];
}
This works, but the [NSRunLoop currentRunLoop] is pausing the entire app, blocking everything for 3 seconds.
How do I get rid of the block on the main thread and still get the same result?
A simple fade (not a cross-fade) can go like this:
// change a label's text after some delay by fading
// out, changing the text, then fading back in
- (void)fadeLabel:(UILabel *)label toText:(NSString *)toText completion:(void (^)(BOOL))completion {
[UIView animateWithDuration:0.2 delay:0.0 options:UIViewAnimationOptionCurveEaseInOut animations:^{
label.alpha = 0.0;
} completion:^(BOOL finished) {
label.text = toText;
[UIView animateWithDuration:0.2 delay:0.0 options:UIViewAnimationOptionCurveEaseIn animations:^{
label.alpha = 1.0;
} completion:completion];
}];
}
// simpler signature that can be done on a perform
- (void)changeLabelText:(NSString *)toText {
[self fadeLabel:self.myLabel toText:toText completion:nil];
}
// set the label to something, then change it with a fade, then change it back
self.myLabel.text = #"text";
[self performSelector:#selector(changeLabelText:) withObject:#"hola!" afterDelay:4];
[self performSelector:#selector(changeLabelText:) withObject:#"text" afterDelay:8];
You could also nest the calls' completion blocks (and add a delay param) to do something similar without the performs. To do a cross-fade, apply a similar technique with two labels (that have the same frame) where one's alpha is zero and the other's alpha is one.
I have the following code
[UIView animateWithDuration:2 delay:0 options:UIViewAnimationOptionCurveEaseInOut animations:^{
mainPage.frame=CGRectMake(0, -[UIScreen mainScreen].bounds.size.width,[UIScreen mainScreen].bounds.size.height,[UIScreen mainScreen].bounds.size.width);
} completion:nil];
Is there any way to control the animation duration of the subviews of mainPage.
You can use UIView:animateKeyframesWithDuration then use UIView:addKeyframeWithRelativeStartTime to set its start time and duration
[UIView animateKeyframesWithDuration:2 delay:0 options:0 animations:^{
[UIView addKeyframeWithRelativeStartTime:0.32 relativeDuration:0.68 animations:^{
view.frame = frame;
}];
[UIView addKeyframeWithRelativeStartTime:0.5 relativeDuration:1 animations:^{
subview.frame = frame2;
}];
} completion:^(BOOL finished) {
}];
If you want the subviews to animate with a different duration then you'll need to animate each of them separately. You can loop through the mainPage.subviews array and issue an animateWithDuration:delay:options:animations:completion: call to each subview in turn, each with a different duration.
I am planning to do an app which has a continuous change of colors in the background. In my idea, there should be an UIView animation after the other one that should repeat itself again and again. This my attempt
self.view.backgroundColor = [UIColor whiteColor];
[UIView animateWithDuration:4 delay:0 options: UIViewAnimationOptionRepeat | UIViewAnimationOptionCurveEaseInOut | UIViewAnimationOptionAutoreverse animations:^{
[UIView animateWithDuration:1 delay:0 options:UIViewAnimationOptionCurveEaseInOut animations:^{
self.view.backgroundColor = [UIColor yellowColor];
NSLog(#"1");
} completion:^(BOOL finished){
[UIView animateWithDuration:1 delay:0 options:UIViewAnimationOptionCurveEaseInOut animations:^{
self.view.backgroundColor = [UIColor greenColor];
NSLog(#"2");
} completion:^(BOOL finished){
[UIView animateWithDuration:1 delay:0 options:UIViewAnimationOptionCurveEaseInOut animations:^{
self.view.backgroundColor = [UIColor redColor];
NSLog(#"3");
} completion:^(BOOL finished){
[UIView animateWithDuration:1 delay:0 options:UIViewAnimationOptionCurveEaseInOut animations:^{
self.view.backgroundColor = [UIColor purpleColor];
NSLog(#"4");
} completion:NULL];
}];
}];
}];
} completion:NULL];
However this doesn't only look messy, but also doesn't repeat itself. Any advice?
Have an array of colours and a currentColorIndex property. Something which gives you the list of colours and a current position in the list. Now have a single method with a single animateWithDuration: in it. In that method, get the next colour and then update the index (wrapping back to 0 when it gets to the end) and run the animation. In the animation completion block, call the method again.
Right now I have an IBAction for a button which generates a random number with each number assigned to display text in a UILabel. Rather than just appear, I would like the text to fade in or any other interesting animation would be cool too. Does anyone know a simple way to make this happen?
Right now I just use
labelMain.text = #"my text";
I know this is a bit stale (11 months old), but I think it's worth mentioning an alternative to the other approaches posted, which I feel is a better solution.
Make use of the UIView transitionWithView:duration:options:animations:completion class-level method, like this:
NSTimeInterval duration = 0.5f;
[UIView transitionWithView:labelMain
duration:duration
options:UIViewAnimationOptionTransitionCrossDissolve
animations:^{
labelMain.text = #"new value";
} completion:nil];
This will cross-fade from the previous value of labelMain.text to "new value".
This approach works on other view values as well, such as changing the image of a UIImageView, for instance.
See Apple's docs on the topic.
The following code will give you fading effect on your label.
- (IBAction)buttonClicked:(UIButton *)sender
{
labelMain.alpha = 0;
[UIView animateWithDuration:0.5 delay:0 options:UIViewAnimationOptionCurveEaseIn
animations:^{ labelMain.alpha = 1;}
completion:nil];
}
label.text = #"old text";
[UIView animateWithDuration:0.4 animations:^{
label.alpha = 0.0f;
} completion:^(BOOL finished) {
label.text = #"next text";
[UIView animateWithDuration:0.4 animations:^{
label.alpha = 1.0f;
} completion:^(BOOL finished) {
NSLog(#"finished transition");
}];
}];
Try this:
[labelMain setAlpha:0];
[UIView beginAnimations:nil context:NULL];
[UIView setAnimationDuration:0.8];
[labelMain setAlpha:1];
[UIView commitAnimations];
Changing the duration is pretty simple - just adjust the value 0.8 in the code.
// fade out the current value
[UIView animateWithDuration:0.2
delay:0
options:0
animations:^{
labelMain.alpha = 0.0f;
}
completion:^(BOOL finished) {
// set the new value and fade in
labelMain.text = newValue;
[UIView animateWithDuration:0.2
delay:0
options:0
animations:^{
labelMain.alpha = 1.0f;
}
completion:nil];
}];
This will look like cross fade animation
[UIView animateWithDuration:0.5 delay:0 options:UIViewAnimationOptionCurveEaseOut
animations:^{
labelMain.alpha = 0;
[UIView animateWithDuration:0.5 delay:0 options:UIViewAnimationOptionCurveEaseIn
animations:^{ labelMain.alpha = 1;}
completion:nil];
} completion:nil];