在ios中运用core animation暂停和继续动画

本文转载至 http://blog.csdn.net/wildfireli/article/details/23191861

暂停和继续动画的核心代码如下：

1. <pre name="code" class="cpp">//暂停layer上面的动画
2. - (void)pauseLayer:(CALayer*)layer
3. {
4. CFTimeInterval pausedTime = [layer convertTime:CACurrentMediaTime() fromLayer:nil];
5. layer.speed = 0.0;
6. layer.timeOffset = pausedTime;
7. }
8. //继续layer上面的动画
9. - (void)resumeLayer:(CALayer*)layer
10. {
11. CFTimeInterval pausedTime = [layer timeOffset];
12. layer.speed = 1.0;
13. layer.timeOffset = 0.0;
14. layer.beginTime = 0.0;
15. CFTimeInterval timeSincePause = [layer convertTime:CACurrentMediaTime() fromLayer:nil] - pausedTime;
16. layer.beginTime = timeSincePause;
17. }</pre><br>
18. <pre></pre>
19. <p>附上完整代码</p>
20. <p></p>
21. <p class="p1">AnimationPauseViewController.h</p>
22. <pre name="code" class="cpp">#import <UIKit/UIKit.h>
23. @interface AnimationPauseViewController : UIViewController {
24. UIImageView *soccer;
25. BOOL isPause;
26. UIButton *controlButton;
27. }
28. @property (nonatomic, retain) IBOutlet UIImageView *soccer;
29. - (IBAction)clickControlButton:(id)sender;
30. @property (nonatomic, retain) IBOutlet UIButton *controlButton;
31. @end</pre><br>
32. <p></p>
33. <p class="p1">AnimationPauseViewController.m</p>
34. <p></p><pre name="code" class="cpp">#import "AnimationPauseViewController.h"
35. #import <QuartzCore/QuartzCore.h>
36. @implementation AnimationPauseViewController
37. @synthesize controlButton;
38. @synthesize soccer;
39. - (void)dealloc
40. {
41. [soccer release];
42. [controlButton release];
43. [super dealloc];
44. }
45. - (void)didReceiveMemoryWarning
46. {
47. // Releases the view if it doesn't have a superview.
48. [super didReceiveMemoryWarning];
49. // Release any cached data, images, etc that aren't in use.
50. }
51. - (void)addAnimations
52. {
53. //让足球来回移动
54. CABasicAnimation *translation = [CABasicAnimation animationWithKeyPath:@"position"];
55. translation.fromValue = [NSValue valueWithCGPoint:CGPointMake(24, 240)];
56. translation.toValue = [NSValue valueWithCGPoint:CGPointMake(320- 24, 240)];
57. translation.duration = 2;
58. translation.repeatCount = HUGE_VALF;
59. translation.autoreverses = YES;
60. //让足球来回转动
61. CABasicAnimation *rotation = [CABasicAnimation animationWithKeyPath:@"transform.rotation.z"];
62. //kCAMediaTimingFunctionLinear 表示时间方法为线性，使得足球匀速转动
63. rotation.timingFunction = [CAMediaTimingFunction functionWithName:kCAMediaTimingFunctionLinear];
64. rotation.toValue = [NSNumber numberWithFloat:4 * M_PI];
65. rotation.duration = 2;
66. rotation.repeatCount = HUGE_VALF;
67. rotation.autoreverses = YES;
68. [soccer.layer addAnimation:rotation forKey:@"rotation"];
69. [soccer.layer addAnimation:translation forKey:@"translation"];
70. }
71. #pragma mark - View lifecycle
72. - (void)viewDidLoad
73. {
74. [super viewDidLoad];
75. [self addAnimations];
76. }
77. - (void)viewDidUnload
78. {
79. [self setSoccer:nil];
80. [self setControlButton:nil];
81. [super viewDidUnload];
82. }
83. - (BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)interfaceOrientation
84. {
85. // Return YES for supported orientations
86. return (interfaceOrientation == UIInterfaceOrientationPortrait);
87. }
88. //暂停layer上面的动画
89. - (void)pauseLayer:(CALayer*)layer
90. {
91. CFTimeInterval pausedTime = [layer convertTime:CACurrentMediaTime() fromLayer:nil];
92. layer.speed = 0.0;
93. layer.timeOffset = pausedTime;
94. }
95. //继续layer上面的动画
96. - (void)resumeLayer:(CALayer*)layer
97. {
98. CFTimeInterval pausedTime = [layer timeOffset];
99. layer.speed = 1.0;
100. layer.timeOffset = 0.0;
101. layer.beginTime = 0.0;
102. CFTimeInterval timeSincePause = [layer convertTime:CACurrentMediaTime() fromLayer:nil] - pausedTime;
103. layer.beginTime = timeSincePause;
104. }
105. - (void)pauseSoccer
106. {
107. isPause = YES;
108. [controlButton setTitle:@"继续" forState:UIControlStateNormal];
109. [self pauseLayer:soccer.layer];
110. }
111. - (void)resumeSoccer
112. {
113. isPause = NO;
114. [controlButton setTitle:@"暂停" forState:UIControlStateNormal];
115. [self resumeLayer:soccer.layer];
116. }
117. - (IBAction)clickControlButton:(id)sender {
118. if (isPause) {
119. [self resumeSoccer];
120. }else{
121. [self pauseSoccer];
122. }
123. }
124. @end</pre><br>
125. <br>
126. <p></p>