Mixing
Core Animation is not working with “alpha” value
Before this code, my movie pic alpha is set to 0,
CABasicAnimation* fadein= [CABasicAnimation animationWithKeyPath:@"alpha"];
[fadein setToValue:[NSNumber numberWithFloat:1.0]];
[fadein setDuration:0.5];
[[moviepic layer]addAnimation:fadein forKey:@"alpha"];
Nothing happened, if I set alpha to 0.5 beforehand instead, the alpha remains at 0.5 and not animating to 1.
I've seen a code using UIView beginAnimations: around, but I'm teaching core animation so I wondered why CABasicAnimation can't do simple task like this?
ios core-animation alpha cabasicanimation
asked Sep 23 '11 at 1:49
5argon
1,24811531
add a comment |
Before this code, my movie pic alpha is set to 0,
CABasicAnimation* fadein= [CABasicAnimation animationWithKeyPath:@"alpha"];
[fadein setToValue:[NSNumber numberWithFloat:1.0]];
[fadein setDuration:0.5];
[[moviepic layer]addAnimation:fadein forKey:@"alpha"];
Nothing happened, if I set alpha to 0.5 beforehand instead, the alpha remains at 0.5 and not animating to 1.
I've seen a code using UIView beginAnimations: around, but I'm teaching core animation so I wondered why CABasicAnimation can't do simple task like this?
ios core-animation alpha cabasicanimation
asked Sep 23 '11 at 1:49
5argon
1,24811531
add a comment |
Before this code, my movie pic alpha is set to 0,
CABasicAnimation* fadein= [CABasicAnimation animationWithKeyPath:@"alpha"];
[fadein setToValue:[NSNumber numberWithFloat:1.0]];
[fadein setDuration:0.5];
[[moviepic layer]addAnimation:fadein forKey:@"alpha"];
Nothing happened, if I set alpha to 0.5 beforehand instead, the alpha remains at 0.5 and not animating to 1.
I've seen a code using UIView beginAnimations: around, but I'm teaching core animation so I wondered why CABasicAnimation can't do simple task like this?
ios core-animation alpha cabasicanimation
asked Sep 23 '11 at 1:49
5argon
1,24811531
Before this code, my movie pic alpha is set to 0,
CABasicAnimation* fadein= [CABasicAnimation animationWithKeyPath:@"alpha"];
[fadein setToValue:[NSNumber numberWithFloat:1.0]];
[fadein setDuration:0.5];
[[moviepic layer]addAnimation:fadein forKey:@"alpha"];
Nothing happened, if I set alpha to 0.5 beforehand instead, the alpha remains at 0.5 and not animating to 1.
I've seen a code using UIView beginAnimations: around, but I'm teaching core animation so I wondered why CABasicAnimation can't do simple task like this?
ios core-animation alpha cabasicanimation
ios core-animation alpha cabasicanimation
asked Sep 23 '11 at 1:49
5argon
1,24811531
asked Sep 23 '11 at 1:49
5argon
1,24811531
edited Apr 14 '13 at 4:43
asked Sep 23 '11 at 1:49
5argon
1,24811531
asked Sep 23 '11 at 1:49
5argon
1,24811531
asked Sep 23 '11 at 1:49
5argon
1,24811531
1,24811531
add a comment |
add a comment |
3 Answers
3
active
oldest
votes
[CABasicAnimation animationWithKeyPath:@"opacity"];
UIView exposes this as alpha where as CALayer exposes this as opacity.
edited Sep 23 '11 at 4:24
Evan
4,96111843
answered Sep 23 '11 at 3:12
ohho
29.7k59214347
What O_o I'll try this soon. But is there anymore case like this? And where can I check that what can I use for KeyPath? (normally I'd check on object's property which has setAlpha in it but in this case it doesn't match...)
– 5argon
Sep 23 '11 at 16:30
4
@Sargon With Core Animation you are animatingCALayerproperties, notUIViewproperties, so the layer is the place to look for correct property names - see:view.layer.
– Palimondo
Sep 27 '11 at 12:23
add a comment |
@ohho answers the posted question. Mine will be a bit more generic. For a list what can and how be animated with CABasicAnimation please refer to Apple's documentation
answered Oct 28 '15 at 10:57
Julian Król
7,82043759
add a comment |
For Swift:
let opacity = CABasicAnimation(keyPath: "opacity")
opacity.fromValue = fromValue
opacity.toValue = toValue
opacity.duration = duration
opacity.beginTime = CACurrentMediaTime() + beginTime //If a delay is needed
view.layer.add(opacity, forKey: nil)
If you want to keep the final alpha value, you have to set the current view controller as the delegate of the opacity animation:
opacity.delegate = self
And, in the delegate function animationDidStop, you should do:
extension ViewController: CAAnimationDelegate {
func animationDidStop(_ anim: CAAnimation, finished flag: Bool) {
view.alpha = toValue
}
}
answered Nov 19 '18 at 12:05
Ginés SM
633
add a comment |
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3 Answers
3
active
oldest
votes
3 Answers
3
active
oldest
votes
active
oldest
votes
active
oldest
votes
[CABasicAnimation animationWithKeyPath:@"opacity"];
UIView exposes this as alpha where as CALayer exposes this as opacity.
edited Sep 23 '11 at 4:24
Evan
4,96111843
answered Sep 23 '11 at 3:12
ohho
29.7k59214347
What O_o I'll try this soon. But is there anymore case like this? And where can I check that what can I use for KeyPath? (normally I'd check on object's property which has setAlpha in it but in this case it doesn't match...)
– 5argon
Sep 23 '11 at 16:30
4
@Sargon With Core Animation you are animatingCALayerproperties, notUIViewproperties, so the layer is the place to look for correct property names - see:view.layer.
– Palimondo
Sep 27 '11 at 12:23
add a comment |
[CABasicAnimation animationWithKeyPath:@"opacity"];
UIView exposes this as alpha where as CALayer exposes this as opacity.
edited Sep 23 '11 at 4:24
Evan
4,96111843
answered Sep 23 '11 at 3:12
ohho
29.7k59214347
What O_o I'll try this soon. But is there anymore case like this? And where can I check that what can I use for KeyPath? (normally I'd check on object's property which has setAlpha in it but in this case it doesn't match...)
– 5argon
Sep 23 '11 at 16:30
4
@Sargon With Core Animation you are animatingCALayerproperties, notUIViewproperties, so the layer is the place to look for correct property names - see:view.layer.
– Palimondo
Sep 27 '11 at 12:23
add a comment |
[CABasicAnimation animationWithKeyPath:@"opacity"];
UIView exposes this as alpha where as CALayer exposes this as opacity.
edited Sep 23 '11 at 4:24
Evan
4,96111843
answered Sep 23 '11 at 3:12
ohho
29.7k59214347
[CABasicAnimation animationWithKeyPath:@"opacity"];
UIView exposes this as alpha where as CALayer exposes this as opacity.
edited Sep 23 '11 at 4:24
Evan
4,96111843
answered Sep 23 '11 at 3:12
ohho
29.7k59214347
edited Sep 23 '11 at 4:24
Evan
4,96111843
edited Sep 23 '11 at 4:24
Evan
4,96111843
edited Sep 23 '11 at 4:24
Evan
4,96111843
4,96111843
answered Sep 23 '11 at 3:12
ohho
29.7k59214347
answered Sep 23 '11 at 3:12
ohho
29.7k59214347
answered Sep 23 '11 at 3:12
ohho
29.7k59214347
29.7k59214347
What O_o I'll try this soon. But is there anymore case like this? And where can I check that what can I use for KeyPath? (normally I'd check on object's property which has setAlpha in it but in this case it doesn't match...)
– 5argon
Sep 23 '11 at 16:30
4
@Sargon With Core Animation you are animatingCALayerproperties, notUIViewproperties, so the layer is the place to look for correct property names - see:view.layer.
– Palimondo
Sep 27 '11 at 12:23
add a comment |
What O_o I'll try this soon. But is there anymore case like this? And where can I check that what can I use for KeyPath? (normally I'd check on object's property which has setAlpha in it but in this case it doesn't match...)
– 5argon
Sep 23 '11 at 16:30
4
@Sargon With Core Animation you are animatingCALayerproperties, notUIViewproperties, so the layer is the place to look for correct property names - see:view.layer.
– Palimondo
Sep 27 '11 at 12:23
What O_o I'll try this soon. But is there anymore case like this? And where can I check that what can I use for KeyPath? (normally I'd check on object's property which has setAlpha in it but in this case it doesn't match...)
– 5argon
Sep 23 '11 at 16:30
What O_o I'll try this soon. But is there anymore case like this? And where can I check that what can I use for KeyPath? (normally I'd check on object's property which has setAlpha in it but in this case it doesn't match...)
– 5argon
Sep 23 '11 at 16:30
4
4
@Sargon With Core Animation you are animating
CALayer properties, not UIView properties, so the layer is the place to look for correct property names - see: view.layer.– Palimondo
Sep 27 '11 at 12:23
@Sargon With Core Animation you are animating
CALayer properties, not UIView properties, so the layer is the place to look for correct property names - see: view.layer.– Palimondo
Sep 27 '11 at 12:23
add a comment |
@ohho answers the posted question. Mine will be a bit more generic. For a list what can and how be animated with CABasicAnimation please refer to Apple's documentation
answered Oct 28 '15 at 10:57
Julian Król
7,82043759
add a comment |
@ohho answers the posted question. Mine will be a bit more generic. For a list what can and how be animated with CABasicAnimation please refer to Apple's documentation
answered Oct 28 '15 at 10:57
Julian Król
7,82043759
add a comment |
@ohho answers the posted question. Mine will be a bit more generic. For a list what can and how be animated with CABasicAnimation please refer to Apple's documentation
answered Oct 28 '15 at 10:57
Julian Król
7,82043759
@ohho answers the posted question. Mine will be a bit more generic. For a list what can and how be animated with CABasicAnimation please refer to Apple's documentation
answered Oct 28 '15 at 10:57
Julian Król
7,82043759
answered Oct 28 '15 at 10:57
Julian Król
7,82043759
answered Oct 28 '15 at 10:57
Julian Król
7,82043759
answered Oct 28 '15 at 10:57
Julian Król
7,82043759
7,82043759
add a comment |
add a comment |
For Swift:
let opacity = CABasicAnimation(keyPath: "opacity")
opacity.fromValue = fromValue
opacity.toValue = toValue
opacity.duration = duration
opacity.beginTime = CACurrentMediaTime() + beginTime //If a delay is needed
view.layer.add(opacity, forKey: nil)
If you want to keep the final alpha value, you have to set the current view controller as the delegate of the opacity animation:
opacity.delegate = self
And, in the delegate function animationDidStop, you should do:
extension ViewController: CAAnimationDelegate {
func animationDidStop(_ anim: CAAnimation, finished flag: Bool) {
view.alpha = toValue
}
}
answered Nov 19 '18 at 12:05
Ginés SM
633
add a comment |
For Swift:
let opacity = CABasicAnimation(keyPath: "opacity")
opacity.fromValue = fromValue
opacity.toValue = toValue
opacity.duration = duration
opacity.beginTime = CACurrentMediaTime() + beginTime //If a delay is needed
view.layer.add(opacity, forKey: nil)
If you want to keep the final alpha value, you have to set the current view controller as the delegate of the opacity animation:
opacity.delegate = self
And, in the delegate function animationDidStop, you should do:
extension ViewController: CAAnimationDelegate {
func animationDidStop(_ anim: CAAnimation, finished flag: Bool) {
view.alpha = toValue
}
}
answered Nov 19 '18 at 12:05
Ginés SM
633
add a comment |
For Swift:
let opacity = CABasicAnimation(keyPath: "opacity")
opacity.fromValue = fromValue
opacity.toValue = toValue
opacity.duration = duration
opacity.beginTime = CACurrentMediaTime() + beginTime //If a delay is needed
view.layer.add(opacity, forKey: nil)
If you want to keep the final alpha value, you have to set the current view controller as the delegate of the opacity animation:
opacity.delegate = self
And, in the delegate function animationDidStop, you should do:
extension ViewController: CAAnimationDelegate {
func animationDidStop(_ anim: CAAnimation, finished flag: Bool) {
view.alpha = toValue
}
}
answered Nov 19 '18 at 12:05
Ginés SM
633
For Swift:
let opacity = CABasicAnimation(keyPath: "opacity")
opacity.fromValue = fromValue
opacity.toValue = toValue
opacity.duration = duration
opacity.beginTime = CACurrentMediaTime() + beginTime //If a delay is needed
view.layer.add(opacity, forKey: nil)
If you want to keep the final alpha value, you have to set the current view controller as the delegate of the opacity animation:
opacity.delegate = self
And, in the delegate function animationDidStop, you should do:
extension ViewController: CAAnimationDelegate {
func animationDidStop(_ anim: CAAnimation, finished flag: Bool) {
view.alpha = toValue
}
}
answered Nov 19 '18 at 12:05
Ginés SM
633
edited Nov 20 '18 at 8:09
answered Nov 19 '18 at 12:05
Ginés SM
633
answered Nov 19 '18 at 12:05
Ginés SM
633
answered Nov 19 '18 at 12:05
Ginés SM
633
633
add a comment |
add a comment |
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