CALayer

一、简介

1.CALayer

简单的说是层（图层）的概念，类似与PS中的图层。一个用来完成绘制、渲染、动画等效果的可见的容器。

2.CALayer 与 UIView 的联系与区别

UIView中有一个layer属性，为根图层。UIView之所以能显示在屏幕上，完全是因为它内部的CALayer对象。在创建UIView对象时，UIView内部会自动创建一个层(即CALayer对象)，通过UIView的layer属性可以访问这个层。当UIView需要显示到屏幕上时，会调用drawRect:方法进行绘图，并且会将所有内容绘制在自己的层上，绘图完毕后，系统会将层拷贝到屏幕上，于是就完成了UIView的显示。UIView本身不具备显示的功能，显示的是UIView的CALayer。
UIView可以通过subviews属性访问所有的子视图，同样地，CALayer也可以通过sublayers属性访问所有的子层；UIView可以通过superview属性访问父视图，同样地，CALayer也可以通过superlayer属性访问父层。
UIView可以通过addSubview:方法添加子视图，同样地，CALayer可以通过addSublayer:方法添加子层。

在使用时，往往CALayer和UIView都能实现相同的显示效果，但是UIView具有交互的能力，可以处理事件。如果显示出来的东西需要跟用户进行交互的话，那么就要使用用UIView。

3.常用属性

注：

• 在CALayer中很少使用frame属性，因为frame本身不支持隐式动画，通常使用bounds和position代替
• anchorPoint属性是图层的锚点，范围在（0_1,01）表示在x、y轴的比例，这个点决定着CALayer身上的哪个点会与position所指定的位置重合，当图层中心点固定后，调整anchorPoint即可达到调整图层显示位置的作用（因为它永远和position重合）

4.隐式动画属性

每一个UIView内部都默认关联着一个CALayer，这个CALayer为Root Layer（根层）。对于所有的非Root Layer，即手动创建的CALayer对象，当对非Root Layer的部分属性进行相应的修改时，默认会自动产生一些动画效果，这些属性称为Animatable Properties(可动画属性)。隐式属性动画的本质是这些属性的变动默认隐含了CABasicAnimation动画实现，例如修改bounds属性会产生缩放动画，修改backgroundColor属性会产生背景色的渐变动画，修改position属性会产生平移动画。

可以通过动画事务(CATransaction)关闭默认的隐式动画效果
[CATransactionbegin];
[CATransactionsetDisableActions:YES];
self.myview.layer.position= CGPointMake(100, 100);
[CATransactioncommit];

二、简单使用

1. 设置阴影

  imageView.layer.shadowColor = [UIColor grayColor].CGColor;  //阴影颜色
  imageView.layer.shadowOffset = CGSizeMake(10, 10); //阴影偏移量
  imageView.layer.shadowOpacity = 0.5;  //阴影透明度

2.设置圆角

 imageView.layer.masksToBounds = YES;   
 imageView.layer.cornerRadius = 10;     //当cornerRadius等于边长的一半时，就是圆

3.设置边框

 imageView.layer.borderWidth = 5;
 imageView.layer.borderColor = [UIColor redColor].CGColor;

4.设置旋转

 imageView.layer.transform = CATransform3DMakeRotation(M_PI_4, 0, 0, 1);// 顺时针旋转45

5.绘制图层

绘制图层有两种方法

1.通过图层代理drawLayer: inContext:方法绘制
2.通过自定义图层drawInContext:方法绘制
不管使用哪种方法绘制完必须调用图层的setNeedDisplay方法.

① 使用代理方法绘制图层
通过代理方法进行图层绘图只要指定图层的代理，然后在代理对象中重写-(void)drawLayer:(CALayer *)layer inContext:(CGContextRef)ctx方法即可。需要注意这个方法虽然是代理方法但是不用手动实现CALayerDelegate，因为CALayer定义中给NSObject做了分类扩展，所有的NSObject都包含这个方法。另外设置完代理后必须要调用图层的setNeedDisplay方法，否则绘制的内容无法显示。

例

- (void)viewDidLoad {
    [super viewDidLoad];

    CALayer * layer = [[CALayer alloc]init];
    layer.bounds = CGRectMake(0, 0, 100, 100);
    layer.position = CGPointMake(50, 50);
    layer.masksToBounds = YES;
    layer.cornerRadius = 50;
    layer.borderWidth = 2;
    layer.borderColor = [UIColor yellowColor].CGColor;

    layer.delegate = self; //设置代理
    [self.view.layer addSublayer:layer]; //添加图层
    [layer setNeedsDisplay]; //重绘
}

- (void)drawLayer:(CALayer *)layer inContext:(CGContextRef)ctx{
    CGContextSaveGState(ctx);
    CGContextScaleCTM(ctx, 1, -1); //转换坐标系
    CGContextTranslateCTM(ctx, 0, -100);
    UIImage * image = [UIImage imageNamed:@"me"];
    CGContextDrawImage(ctx, CGRectMake(0, 0, 100, 100), image.CGImage);
    CGContextRestoreGState(ctx);
}

② 使用自定义图层绘制图层
创建一个CALayer的子类，然后重写drawInContext:方法，在方法中使用Quartz2D API进行绘图；
同样，使用时，必须要调用图层的setNeedDisplay方法，才会触发drawInContext:方法的调用。

Core Animation

一、简介

1.概念

Core Animation 是作用在CALayer上的，使用Core Animation 创建动画不仅简单，而且还有更好的性能，因为Core Animation 是在单独的线程中完成的，不会阻塞主线程，而且只会重绘界面上变化的部分（局部刷新）。

2.分类

基础动画、关键帧动画都属于属性动画，是通过修改属性值产生动画效果，只需要设置初始值和结束值，中间的过程动画（“补间动画”）是由系统自动计算产生。和基础动画不同的是关键帧动画可以设置多个属性值，每两个属性中间的补间动画由系统自动完成，基础动画也可以看成是有两个关键帧的关键帧动画。

二、使用

1. CAAnimation

CAAnimation 是基类，其属性它的子类也拥有。它不能直接使用。

代理方法 : 给NSObject添加了分类，所以任何对象，都可以成为CAAnimation的代理。

动画开始的时候调用 - (void)animationDidStart:(CAAnimation *)anim;
动画停止的时候调用 - (void)animationDidStop:(CAAnimation *)anim finished:(BOOL)flag;

2.CAPropertyAnimation

位移动画通常使用属性动画控制 CALayer 的 position 属性持续改变，如果要实现 CALayer 的旋转、缩放等动画效果，若在平面上（二维空间）上，则修改 CALayer 的 affineTransform 属性，该属性值为一个CGAffineTransform 对象；若在三维空间上，则修改 CALayer 的 transform 属性，该属性值为一个 CATransform3D 对象。

CATransform3D : 三维变换矩阵

3.CABasicAnimation 和 CAKeyframeAnimation

CAPropertyAnimation的子类，首先创建初始化一个CALayer，初始化动画CABasicAnimation是设置 fromValue 和 toValue ，CAKeyframeAnimation是设置 values ，再设置其他动画属性，将动画添加到图层上。

CALayer 为动画提供的方法

① 位移动画
CABasicAnimation

CABasicAnimation * anim = [CABasicAnimation animationWithKeyPath:@"position"];
anim.fromValue = [NSValue valueWithCGPoint:self.layer.position];
CGPoint toPoint = CGPointMake(300, 300);
anim.toValue = [NSValue valueWithCGPoint:toPoint];
anim.duration = 1.0;
self.layer.position = toPoint;
anim.removedOnCompletion = YES;
[self.layer addAnimation:anim forKey:@"KCBasicAnimation_Position"];

CAKeyframeAnimation

CAKeyframeAnimation * keyframeAnimation = [CAKeyframeAnimation animationWithKeyPath:@"position"];
NSValue * value1 = [NSValue valueWithCGPoint:self.layer.position];
NSValue * value2 = [NSValue valueWithCGPoint:CGPointMake(80, 220)];
NSValue * value3 = [NSValue valueWithCGPoint:CGPointMake(45, 300)];
NSValue * value4 = [NSValue valueWithCGPoint:CGPointMake(55, 400)];
NSArray * values=@[value1,value2,value3,value4];
keyframeAnimation.values = values;
keyframeAnimation.duration = 2.0;
[self.layer addAnimation:keyframeAnimation forKey:@"KCKeyframeAnimation_Position"];    

通过描绘路径进行关键帧动画控制

CAKeyframeAnimation * keyframeAnimation=[CAKeyframeAnimation animationWithKeyPath:@"position"];
CGMutablePathRef path = CGPathCreateMutable();
CGPathMoveToPoint(path, NULL, self.layer.position.x, self.layer.position.y);
CGPathAddCurveToPoint(path, NULL, 160, 280, -30, 300, 55, 400);
keyframeAnimation.path = path;
CGPathRelease(path);
keyframeAnimation.duration = 4.0;
keyframeAnimation.removedOnCompletion = YES;
[self.layer addAnimation:keyframeAnimation forKey:@"KCKeyframeAnimation_Position"];

② 旋转动画
CABasicAnimation

CABasicAnimation * anim = [CABasicAnimation animationWithKeyPath:@"transform"];
CATransform3D fromValue = self.layer.transform;
anim.fromValue = [NSValue valueWithCATransform3D:fromValue];
CATransform3D toValue = CATransform3DRotate(fromValue, M_PI, 1, 0, 0);
anim.toValue = [NSValue valueWithCATransform3D:toValue];
anim.duration = 0.5;
self.layer.transform = toValue;
anim.removedOnCompletion = YES;
[self.layer addAnimation:anim forKey:@"KCBasicAnimation_Rotate"];

CAKeyframeAnimation

CAKeyframeAnimation * keyframeAnimation = [CAKeyframeAnimation animationWithKeyPath:@"transform"];
NSValue * value1 = [NSValue valueWithCATransform3D:self.layer.transform];
NSValue * value2 = [NSValue valueWithCATransform3D:CATransform3DMakeRotation(M_PI, 1, 0, 0)];
NSValue * value3 = [NSValue valueWithCATransform3D:CATransform3DMakeRotation(M_PI, 0, 1, 0)];
NSValue * value4 = [NSValue valueWithCATransform3D:CATransform3DMakeRotation(M_PI, 0, 0, 1)];
NSArray * values = @[value1,value2,value3,value4];
keyframeAnimation.values = values;
keyframeAnimation.duration = 2.0;
[self.layer addAnimation:keyframeAnimation forKey:@"KCKeyframeAnimation_Rotate"];

③ 缩放动画
CABasicAnimation

CABasicAnimation * anim = [CABasicAnimation animationWithKeyPath:@"transform"];
CATransform3D fromValue = self.layer.transform;
anim.fromValue = [NSValue valueWithCATransform3D:fromValue];
CATransform3D toValue = CATransform3DScale(fromValue, 0.5, 0.5, 1);
anim.toValue = [NSValue valueWithCATransform3D:toValue];
anim.duration = 0.5;
self.layer.transform = toValue;
anim.removedOnCompletion = YES;
[self.layer addAnimation:anim forKey:@"KCBasicAnimation_Scale"];

CAKeyframeAnimation

CAKeyframeAnimation * keyframeAnimation = [CAKeyframeAnimation animationWithKeyPath:@"transform"];
NSValue * value1 = [NSValue valueWithCATransform3D:self.layer.transform];
NSValue * value2 = [NSValue valueWithCATransform3D:CATransform3DMakeScale(0.5, 0.5, 1)];
NSValue * value3 = [NSValue valueWithCATransform3D:CATransform3DMakeScale(1, 1, 1)];
NSArray * values = @[value1,value2,value3];
keyframeAnimation.values = values;
keyframeAnimation.duration = 2.0;
[self.layer addAnimation:keyframeAnimation forKey:@"KCKeyframeAnimation_Scale"];

④ 动画组
CABasicAnimation

CGPoint fromPoint = self.layer.position;
CGPoint toPoint = CGPointMake(280, fromPoint.y + 300);

CABasicAnimation * moveAnim = [CABasicAnimation animationWithKeyPath:@"position"];
moveAnim.fromValue = [NSValue valueWithCGPoint:fromPoint];
moveAnim.toValue = [NSValue valueWithCGPoint:toPoint];
moveAnim.removedOnCompletion = YES;

CABasicAnimation * transformAnim = [CABasicAnimation animationWithKeyPath:@"transform"];
CATransform3D fromValue = self.layer.transform;
transformAnim.fromValue = [NSValue valueWithCATransform3D:fromValue];
CATransform3D scaleValue = CATransform3DScale(fromValue, 0.5, 0.5, 1);
CATransform3D rotateValue = CATransform3DRotate(fromValue, M_PI, 0, 0, 1);
CATransform3D toValue = CATransform3DConcat(scaleValue, rotateValue);
transformAnim.toValue = [NSValue valueWithCATransform3D:toValue];
transformAnim.cumulative = YES;
transformAnim.repeatCount = 2;
transformAnim.duration = 3;

CAAnimationGroup * animGroup = [CAAnimationGroup animation];
animGroup.animations = @[moveAnim,transformAnim];
animGroup.duration = 6;
[self.layer addAnimation:animGroup forKey:@"KCBasicAnimation_Group"];

CAKeyframeAnimation

CAKeyframeAnimation * moveAnim = [CAKeyframeAnimation animationWithKeyPath:@"position"];
NSValue * move1 = [NSValue valueWithCGPoint:self.layer.position];
NSValue * move2 = [NSValue valueWithCGPoint:CGPointMake(300, 100)];
NSValue * move3 = [NSValue valueWithCGPoint:CGPointMake(300, 300)];
NSValue * move4 = [NSValue valueWithCGPoint:CGPointMake(100, 300)];
NSValue * move5 = [NSValue valueWithCGPoint:CGPointMake(100, 100)];
NSArray * values = @[move1,move2,move3,move4,move5];
moveAnim.values = values;
moveAnim.removedOnCompletion = YES;

CAKeyframeAnimation * transformAnim = [CAKeyframeAnimation animationWithKeyPath:@"transform"];
CATransform3D rotate1 = self.layer.transform;
CATransform3D rotate2 = CATransform3DMakeRotation(M_PI, 1, 0, 0);
CATransform3D rotate3 = CATransform3DMakeRotation(M_PI, 0, 1, 0);
CATransform3D rotate4 = CATransform3DMakeRotation(M_PI, 0, 0, 1);
CATransform3D rotate5 = CATransform3DMakeRotation(M_PI, 1, 1, 1);

CATransform3D scale1 = self.layer.transform;
CATransform3D scale2 = CATransform3DMakeScale(0.5, 0.5, 1);
CATransform3D scale3 = CATransform3DMakeScale(1, 1, 1);
CATransform3D scale4 = CATransform3DMakeScale(0.5, 0.5, 1);
CATransform3D scale5 = CATransform3DMakeScale(1, 1, 1);

NSValue * transform1 = [NSValue valueWithCATransform3D:CATransform3DConcat(rotate1, scale1)];
NSValue * transform2 = [NSValue valueWithCATransform3D:CATransform3DConcat(rotate2, scale2)];
NSValue * transform3 = [NSValue valueWithCATransform3D:CATransform3DConcat(rotate3, scale3)];
NSValue * transform4 = [NSValue valueWithCATransform3D:CATransform3DConcat(rotate4, scale4)];
NSValue * transform5 = [NSValue valueWithCATransform3D:CATransform3DConcat(rotate5, scale5)];
transformAnim.values = @[transform1,transform2,transform3,transform4,transform5];
transformAnim.removedOnCompletion = YES;

CAAnimationGroup * animGroup = [CAAnimationGroup animation];
animGroup.animations = @[moveAnim,transformAnim];
animGroup.duration = 8;
self.layer.position = CGPointMake(100, 100);
[self.layer addAnimation:animGroup forKey:@"KCBasicAnimation_Group"];

④ 动画暂停

-(void)pauseLayer{
    CFTimeInterval interval=[self.layer convertTime:CACurrentMediaTime() fromLayer:nil];
    [self.layer setTimeOffset:interval];
    self.layer.speed=0;
}

⑤ 动画恢复

-(void)resumeLayer{
    CFTimeInterval beginTime= CACurrentMediaTime() - self.layer.timeOffset;
    self.layer.timeOffset = 0;
    self.layer.beginTime = beginTime;
    self.layer.speed=1.0;
}

4.CATransition

CATransition的type属性用于控制动画类型，还有私有动画。

值| 说明 |是否支持方向设置
-----|-----
kCATransitionFade|通过渐隐效果过渡，默认属性值|是
kCATransitionMoveIn|通过移入动画过渡，新视图移到旧视图上面|是
kCATransitionPush|通过推入动画过渡，新视图把旧视图推出去|是
kCATransitionReveal|通过揭开动画过渡，将旧视图移开,同时显示下面的新视图|是
@"cube"|通过立方体旋转动画过渡|是
@"oglFlip"|通过翻转动画过渡|是
@"suckEffect"|通过收缩（吸入）动画过渡|否
@"rippleEffect"|通过水波动画过渡|否
@"pageCurl"|通过向后翻页动画过渡|是
@"pageUnCurl"|通过向前翻页动画过渡|是
@"cameraIrisHollowOpen"|通过相机镜头打开效果动画过渡|否
@"cameraIrisHollowClose"|通过相机镜头关闭效果动画过渡|否

CATransition的subtype属性用于控制动画方向

#import "ViewController.h"
#define IMAGE_COUNT 5

typedef enum {
    GestureDirectionUp = 1,
    GestureDirectionDown,
    GestureDirectionLeft,
    GestureDirectionRight
}GestureDirection;

@interface ViewController () <UIPickerViewDelegate,UIPickerViewDataSource>

@property (nonatomic,strong) UIImageView * imageView;
@property (nonatomic,assign) int currentIndex;
@property (nonatomic,strong) CATransition * transition;
@property (nonatomic,strong) UIPickerView * pickerView;
@property (nonatomic,copy) NSArray * transitions;
@property (nonatomic,assign) BOOL isPop;

@end

@implementation ViewController

- (NSArray *)transitions{
    if (_transitions == nil) {
        _transitions = @[kCATransitionFade,kCATransitionMoveIn,kCATransitionPush,kCATransitionReveal,@"cube",@"oglFlip",@"suckEffect",@"rippleEffect",@"pageCurl",@"pageUnCurl",@"cameralIrisHollowOpen",@"cameraIrisHollowClose"];
    }
    return _transitions;
}

- (void)viewDidLoad {
    [super viewDidLoad];

    self.view.backgroundColor = [UIColor whiteColor];

    CGFloat screenWidth = [UIScreen mainScreen].bounds.size.width;
    CGFloat screenHeight = [UIScreen mainScreen].bounds.size.height;

    self.navigationItem.title = @"转场";
    UIBarButtonItem * rightBarButtonItem = [[UIBarButtonItem alloc]initWithTitle:@"效果" style:UIBarButtonItemStyleDone target:self action:@selector(selectTransition:)];
    self.navigationItem.rightBarButtonItem = rightBarButtonItem;

    self.imageView = [[UIImageView alloc]initWithFrame:self.view.frame];
    self.imageView.backgroundColor = [UIColor whiteColor];
    self.imageView.contentMode = UIViewContentModeScaleAspectFit;
    self.imageView.image = [UIImage imageNamed:@"0.jpg"];
    [self.view addSubview:self.imageView];

    self.pickerView = [[UIPickerView alloc]initWithFrame:CGRectMake(0, screenHeight, screenWidth, 300)];
    self.pickerView.dataSource = self;
    self.pickerView.delegate = self;
    [self.view addSubview:self.pickerView];

    UISwipeGestureRecognizer * upSwipeGesture = [[UISwipeGestureRecognizer alloc]initWithTarget:self action:@selector(swipe:)];
    [upSwipeGesture setDirection:UISwipeGestureRecognizerDirectionUp];
    [self.view addGestureRecognizer:upSwipeGesture];

    UISwipeGestureRecognizer * downSwipeGesture = [[UISwipeGestureRecognizer alloc]initWithTarget:self action:@selector(swipe:)];
    [downSwipeGesture setDirection:UISwipeGestureRecognizerDirectionDown];
    [self.view addGestureRecognizer:downSwipeGesture];

    UISwipeGestureRecognizer * leftSwipeGesture = [[UISwipeGestureRecognizer alloc]initWithTarget:self action:@selector(swipe:)];
    [leftSwipeGesture setDirection:UISwipeGestureRecognizerDirectionLeft];
    [self.view addGestureRecognizer:leftSwipeGesture];

    UISwipeGestureRecognizer * rightSwipeGesture = [[UISwipeGestureRecognizer alloc]initWithTarget:self action:@selector(swipe:)];
    [rightSwipeGesture setDirection:UISwipeGestureRecognizerDirectionRight];
    [self.view addGestureRecognizer:rightSwipeGesture];

    self.transition = [[CATransition alloc]init];
    self.transition.type = kCATransitionFade;
    self.isPop = NO;
}

- (void)selectTransition:(UIBarButtonItem *)btn{
    self.isPop = !self.isPop;
    if (self.isPop) {
        CGContextRef context = UIGraphicsGetCurrentContext();
        [UIView beginAnimations:nil context:context];
        [UIView setAnimationCurve:UIViewAnimationCurveEaseInOut];
        [UIView setAnimationDuration:0.6];
        [self.view bringSubviewToFront:self.pickerView];
        CGFloat screenHeight = [UIScreen mainScreen].bounds.size.height;
        CGFloat pickerViewWidth = [UIScreen mainScreen].bounds.size.width;
        CGFloat pickerViewHeight = 300;
        self.pickerView.frame = CGRectMake(0, screenHeight - pickerViewHeight, pickerViewWidth, pickerViewHeight);
        [UIView commitAnimations];
}
else {
        CGContextRef context = UIGraphicsGetCurrentContext();
        [UIView beginAnimations:nil context:context];
        [UIView setAnimationCurve:UIViewAnimationCurveEaseInOut];
        [UIView setAnimationDuration:0.6];
        CGFloat screenHeight = [UIScreen mainScreen].bounds.size.height;
        CGFloat pickerViewWidth = [UIScreen mainScreen].bounds.size.width;
        CGFloat pickerViewHeight = 300;
        self.pickerView.frame = CGRectMake(0, screenHeight, pickerViewWidth, pickerViewHeight);
        [UIView commitAnimations];
    }
}

-(void)swipe:(UISwipeGestureRecognizer *)gesture{
    if (gesture.direction == UISwipeGestureRecognizerDirectionUp){
        [self transitionAnimation:GestureDirectionUp];
    }
    else if (gesture.direction == UISwipeGestureRecognizerDirectionDown){
        [self transitionAnimation:GestureDirectionDown];
    }
    else if (gesture.direction == UISwipeGestureRecognizerDirectionLeft){
        [self transitionAnimation:GestureDirectionLeft];
    }
    else {
        [self transitionAnimation:GestureDirectionRight];
    }
}

- (void)transitionAnimation:(GestureDirection)gestureDirection{
    switch (gestureDirection) {
        case GestureDirectionUp:
            self.transition.subtype = kCATransitionFromTop;
            break;
        case GestureDirectionDown:
            self.transition.subtype = kCATransitionFromBottom;
           break;
        case GestureDirectionLeft:
            self.transition.subtype = kCATransitionFromRight;
            break;
        case GestureDirectionRight:
            self.transition.subtype = kCATransitionFromLeft;
            break;
        default:
            break;
    }
    self.transition.duration = 1.0f;
    self.imageView.image = [self getImage];
    [self.view.layer addAnimation:self.transition forKey:@"KCTransitionAnimation"];
}

- (UIImage *)getImage{
    self.currentIndex = (self.currentIndex + 1) % IMAGE_COUNT;
    NSString *imageName=[NSString stringWithFormat:@"%i.jpg",_currentIndex];
    return [UIImage imageNamed:imageName];
}

- (NSInteger)numberOfComponentsInPickerView:(UIPickerView *)pickerView{
    return 1;
}

- (NSInteger)pickerView:(UIPickerView *)pickerView numberOfRowsInComponent:(NSInteger)component{
    return self.transitions.count;
}

- (NSString *)pickerView:(UIPickerView *)pickerView titleForRow:(NSInteger)row forComponent:(NSInteger)component{
    return self.transitions[row];
}

- (void)pickerView:(UIPickerView *)pickerView didSelectRow:(NSInteger)row inComponent:(NSInteger)component{
    self.transition.type = self.transitions[row];
}

- (void)didReceiveMemoryWarning {
    [super didReceiveMemoryWarning];
    // Dispose of any resources that can be recreated.
}

@end

5.逐帧动画

通过设置UIImageView的animationImages属性，然后调用它的startAnimating方法去播放一组逐帧图片，但是它存在着很大的性能问题，并且这种方法一旦设置完图片中间的过程就无法控制了。使用CADisplayLink加入到主循环队列中，循环调用目标方法，在这个方法中更新视图内容就可以完成逐帧动画。

- (void)runAnimationWithImageCount:(NSInteger)count AndImageName:(NSString *)name
{
    if (self.myImageView.isAnimating)
    {
        return;
    }
    NSMutableArray * pictArray = [NSMutableArray array];
    for (int i = 0; i < count; i++)
    {
        NSString * pictNum = [NSString stringWithFormat:@"%@_%02d.jpg",name,i];
        // 使用imageNamed的方式加载图片会有缓存，使得占用的内存很大
        //[pictArray addObject:[UIImage imageNamed:pictNum]];
    
        // 直接从文件中读取图片就不会占用太大的内存
        NSBundle * boudle = [NSBundle mainBundle];
        NSString * path = [boudle pathForResource:pictNum ofType:nil];
        [pictArray addObject:[UIImage imageWithContentsOfFile:path]];
    }
    self.myImageView.animationImages = pictArray;
    self.myImageView.animationDuration = (self.myImageView.animationImages.count * 0.07);
    CGFloat delayTime = self.myImageView.animationDuration + 0.5;
    self.myImageView.animationRepeatCount = 1;
    [self.myImageView startAnimating];

    [self.myImageView performSelector:@selector(setAnimationImages:) withObject:nil afterDelay:delayTime];
}

6.UIView动画封装

UIView本身对于基本动画和关键帧动画、转场动画都有相应的封装。

动画使用block方式

UIViewAnimationCurve

UIViewAnimationOptions

UIViewKeyframeAnimationOptions
其中一部分值和 UIViewAnimationOptions 是一样的，不一样的如下：

7.弹簧动画

[UIView animateWithDuration:5.0 delay:0 usingSpringWithDamping:0.1 initialSpringVelocity:1.0 options:UIViewAnimationOptionCurveLinear animations:^{
    self.imageView.center = CGPointMake(300, 300);
} completion:nil];