UIViewAnimationState is the manager class of UIView animation blocks. The system maintains a private global stack that contains all pending animation states. When a state is popped, the corresponding animation begins.
The animations will all go back to QuartzCore (Core Animation).
Drag coefficient
| Signature | CGFloat UIAnimationDragCoefficient(); |
|---|---|
| Available in | 2.0 – |
The drag coefficient is a multiplier applied on time measurements. A large drag coefficient can slow down animations.
The drag coefficient is obtained with the UIAnimationDragCoefficient() function, which in turn is an integer of the key UIAnimationDragCoefficient in the preference file ~/Library/Preferences/com.apple.UIKit.plist.
Drag coefficient will not affect non-UIKit animations.
Animation transitions
Besides the default 4, the iPhoneOS identifies tons of transition effects, all value numerical value starting from 101:
| Numeric | String | Comments |
|---|---|---|
| 0 (UIViewAnimationTransitionNone) | - | |
| 1 (UIViewAnimationTransitionFlipFromLeft) | oglFlip, fromLeft | |
| 2 (UIViewAnimationTransitionFlipFromRight) | oglFlip, fromRight | |
| 3 (UIViewAnimationTransitionCurlUp) | pageCurl | |
| 4 (UIViewAnimationTransitionCurlDown) | pageUnCurl | |
| 101 | pageCurl | Equivalent to UIViewAnimationTransitionCurlUp |
| 102 | pageUnCurl | Equivalent to UIViewAnimationTransitionCurlDown |
| 103 | suckEffect | Sucked to around (160, 360) on the screen. |
| 104 | spewEffect | Not supported? |
| 105 | cameraIris | You should assume the view you're operating on has a black background. |
| 106 | cameraIrisHollowClose | First half of cameraIris. |
| 107 | cameraIrisHollowOpen | Second half of cameraIris. |
| 108 | genieEffect | Not supported? |
| 109 | unGenieEffect | Not supported? |
| 110 | rippleEffect | |
| 111 | twist | Not supported? |
| 112 | tubey | Not supported? |
| 113 | swirl | Not supported? |
| 114 | charminUltra | Not supported? |
| 115 | zoomyIn | Not supported? |
| 116 | zoomyOut | Not supported? |
| 117 | oglApplicationSuspend | Not supported? |
Using suckEffect
The most SDK-compatible way of using suckEffect is to use animation blocks. But the suction point by default is close to nowhere. Therefore you still need to use the undocumented method +[UIView setAnimationPosition:]:
[UIView beginAnimations:@"suck" context:NULL];
[UIView setAnimationTransition:103 forView:myViewContainer cache:YES];
[UIView setAnimationPosition:CGPointMake(12, 345)];
[myView removeFromSuperview];
[UIView commitAnimations];
References
- All animation names: http://www.waterworld.com.hk/en/node/74
- Header: http://github.com/kennytm/iphone-private-frameworks/blob/master/UIKit/UIViewAnimationState.h