Use views for control and layers for eye candy. Layers don’t receive events so it’s easier to use a view for those cases, but when you want to animate a sprite or backgrounds, etc., layers make sense. Events pass right through layers to the backing view so you can have a pretty visual representation without … Read more
How to decide which approach to use? Is there a use case for each one? Always use drawRect:, and never use a UIView as the drawing delegate for any CALayer. how come the delegate method is called if my instance is not defined to be the layer’s delegate? and what mechanism prevents drawRect from being … Read more
It can be easilly done by using Core Animation, animating a mask layer on the layer displaying the text. Try this in any plain UIViewController (you can start with a new Xcode project based on the View-based application project template), or grab my Xcode project here: Note that the CALayer.mask property is only available in … Read more
To expand upon what Nikolai said, the best way to handle this is to use Core Animation to animate the motion of the image or view along a Bezier path. This is accomplished using a CAKeyframeAnimation. For example, I’ve used the following code to animate an image of a view into an icon to indicate … Read more
I can’t find it documented anywhere, but it appears the backgroundColor property of UILabel is not animatable, as your code works fine with a vanilla UIView. This hack appears to work, however, as long as you don’t set the background color of the label view itself: #import <QuartzCore/QuartzCore.h> … theLabel.layer.backgroundColor = [UIColor whiteColor].CGColor; [UIView animateWithDuration:2.0 … Read more
You want to wrap your call in the following: [CATransaction begin]; [CATransaction setValue: (id) kCFBooleanTrue forKey: kCATransactionDisableActions]; layer.position = CGPointMake(x, y); [CATransaction commit];
Instead, have you tried using a crossfade transition on the object itself like this, it’ll give you a nice fade-in fade-out effect from one color to another: Objective C [UIView transitionWithView:myLabel duration:0.25 options:UIViewAnimationOptionTransitionCrossDissolve animations:^{ myLabel.textColor = NEW_COLOR; } completion:^(BOOL finished) { }]; Swift 5 UIView.transition(with: creditsLabel, duration: 0.25, options: .transitionCrossDissolve) { self.creditsLabel.textColor = .red } … Read more
I wrote that post. It’s overkill for a UIView, plus the parameters are geared toward an OSX app. Do this instead. CABasicAnimation *animation = [CABasicAnimation animationWithKeyPath:@”position”]; [animation setDuration:0.05]; [animation setRepeatCount:8]; [animation setAutoreverses:YES]; [animation setFromValue:[NSValue valueWithCGPoint: CGPointMake([lockView center].x – 20.0f, [lockView center].y)]]; [animation setToValue:[NSValue valueWithCGPoint: CGPointMake([lockView center].x + 20.0f, [lockView center].y)]]; [[lockView layer] addAnimation:animation forKey:@”position”]; You’ll … Read more
I had a similar issue recently. I had to manually remove that UITransitionView from the window to fix the problem, then call dismiss on the previous root view controller to ensure its deallocated. The fix is not really very nice but unless you’ve found a better way since posting the question, its the only thing … Read more
Short answer — You need to set the contents scaling: textLayer.contentsScale = [[UIScreen mainScreen] scale]; A while ago I learned that when you have custom drawing code, you have to check for the retina display and scale your graphics accordingly. UIKit takes care of most of this, including font scaling. Not so with CATextLayer. My … Read more