CALayer

一攒读、簡(jiǎn)介

1.CALayer

簡(jiǎn)單的說(shuō)是層（圖層）的概念绸贡，類似與PS中的圖層。一個(gè)用來(lái)完成繪制凛辣、渲染抱既、動(dòng)畫(huà)等效果的可見(jiàn)的容器。

2.CALayer 與 UIView 的聯(lián)系與區(qū)別

UIView中有一個(gè)layer屬性扁誓，為根圖層防泵。UIView之所以能顯示在屏幕上，完全是因?yàn)樗鼉?nèi)部的CALayer對(duì)象蝗敢。在創(chuàng)建UIView對(duì)象時(shí)捷泞，UIView內(nèi)部會(huì)自動(dòng)創(chuàng)建一個(gè)層(即CALayer對(duì)象)，通過(guò)UIView的layer屬性可以訪問(wèn)這個(gè)層寿谴。當(dāng)UIView需要顯示到屏幕上時(shí)锁右，會(huì)調(diào)用drawRect:方法進(jìn)行繪圖，并且會(huì)將所有內(nèi)容繪制在自己的層上，繪圖完畢后咏瑟，系統(tǒng)會(huì)將層拷貝到屏幕上拂到，于是就完成了UIView的顯示。UIView本身不具備顯示的功能码泞，顯示的是UIView的CALayer谆焊。
UIView可以通過(guò)subviews屬性訪問(wèn)所有的子視圖，同樣地浦夷，CALayer也可以通過(guò)sublayers屬性訪問(wèn)所有的子層；UIView可以通過(guò)superview屬性訪問(wèn)父視圖辜王，同樣地劈狐，CALayer也可以通過(guò)superlayer屬性訪問(wèn)父層。
UIView可以通過(guò)addSubview:方法添加子視圖呐馆，同樣地肥缔，CALayer可以通過(guò)addSublayer:方法添加子層。

在使用時(shí)汹来，往往CALayer和UIView都能實(shí)現(xiàn)相同的顯示效果续膳，但是UIView具有交互的能力，可以處理事件收班。如果顯示出來(lái)的東西需要跟用戶進(jìn)行交互的話坟岔，那么就要使用用UIView。

3.常用屬性

注：

• 在CALayer中很少使用frame屬性啼辣，因?yàn)閒rame本身不支持隱式動(dòng)畫(huà)，通常使用bounds和position代替
• anchorPoint屬性是圖層的錨點(diǎn)御滩，范圍在（0_1,01）表示在x鸥拧、y軸的比例，這個(gè)點(diǎn)決定著CALayer身上的哪個(gè)點(diǎn)會(huì)與position所指定的位置重合削解，當(dāng)圖層中心點(diǎn)固定后住涉，調(diào)整anchorPoint即可達(dá)到調(diào)整圖層顯示位置的作用（因?yàn)樗肋h(yuǎn)和position重合）

4.隱式動(dòng)畫(huà)屬性

每一個(gè)UIView內(nèi)部都默認(rèn)關(guān)聯(lián)著一個(gè)CALayer，這個(gè)CALayer為Root Layer（根層）钠绍。對(duì)于所有的非Root Layer舆声，即手動(dòng)創(chuàng)建的CALayer對(duì)象，當(dāng)對(duì)非Root Layer的部分屬性進(jìn)行相應(yīng)的修改時(shí)，默認(rèn)會(huì)自動(dòng)產(chǎn)生一些動(dòng)畫(huà)效果媳握，這些屬性稱為Animatable Properties(可動(dòng)畫(huà)屬性)碱屁。隱式屬性動(dòng)畫(huà)的本質(zhì)是這些屬性的變動(dòng)默認(rèn)隱含了CABasicAnimation動(dòng)畫(huà)實(shí)現(xiàn)，例如修改bounds屬性會(huì)產(chǎn)生縮放動(dòng)畫(huà)蛾找，修改backgroundColor屬性會(huì)產(chǎn)生背景色的漸變動(dòng)畫(huà)娩脾，修改position屬性會(huì)產(chǎn)生平移動(dòng)畫(huà)。

可以通過(guò)動(dòng)畫(huà)事務(wù)(CATransaction)關(guān)閉默認(rèn)的隱式動(dòng)畫(huà)效果
[CATransactionbegin];
[CATransactionsetDisableActions:YES];
self.myview.layer.position= CGPointMake(100, 100);
[CATransactioncommit];

二打毛、簡(jiǎn)單使用

1. 設(shè)置陰影

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

2.設(shè)置圓角

 imageView.layer.masksToBounds = YES;   
 imageView.layer.cornerRadius = 10;     //當(dāng)cornerRadius等于邊長(zhǎng)的一半時(shí)柿赊，就是圓

3.設(shè)置邊框

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

4.設(shè)置旋轉(zhuǎn)

 imageView.layer.transform = CATransform3DMakeRotation(M_PI_4, 0, 0, 1);// 順時(shí)針旋轉(zhuǎn)45

5.繪制圖層

繪制圖層有兩種方法

1.通過(guò)圖層代理drawLayer: inContext:方法繪制
2.通過(guò)自定義圖層drawInContext:方法繪制
不管使用哪種方法繪制完必須調(diào)用圖層的setNeedDisplay方法.

① 使用代理方法繪制圖層
通過(guò)代理方法進(jìn)行圖層繪圖只要指定圖層的代理，然后在代理對(duì)象中重寫-(void)drawLayer:(CALayer *)layer inContext:(CGContextRef)ctx方法即可幻枉。需要注意這個(gè)方法雖然是代理方法但是不用手動(dòng)實(shí)現(xiàn)CALayerDelegate碰声，因?yàn)镃ALayer定義中給NSObject做了分類擴(kuò)展，所有的NSObject都包含這個(gè)方法熬甫。另外設(shè)置完代理后必須要調(diào)用圖層的setNeedDisplay方法胰挑，否則繪制的內(nèi)容無(wú)法顯示。

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; //設(shè)置代理
    [self.view.layer addSublayer:layer]; //添加圖層
    [layer setNeedsDisplay]; //重繪
}

- (void)drawLayer:(CALayer *)layer inContext:(CGContextRef)ctx{
    CGContextSaveGState(ctx);
    CGContextScaleCTM(ctx, 1, -1); //轉(zhuǎn)換坐標(biāo)系
    CGContextTranslateCTM(ctx, 0, -100);
    UIImage * image = [UIImage imageNamed:@"me"];
    CGContextDrawImage(ctx, CGRectMake(0, 0, 100, 100), image.CGImage);
    CGContextRestoreGState(ctx);
}

② 使用自定義圖層繪制圖層
創(chuàng)建一個(gè)CALayer的子類，然后重寫drawInContext:方法，在方法中使用Quartz2D API進(jìn)行繪圖蜀铲；
同樣，使用時(shí)贡这，必須要調(diào)用圖層的setNeedDisplay方法，才會(huì)觸發(fā)drawInContext:方法的調(diào)用厂榛。

Core Animation

一藕坯、簡(jiǎn)介

1.概念

Core Animation 是作用在CALayer上的，使用Core Animation 創(chuàng)建動(dòng)畫(huà)不僅簡(jiǎn)單噪沙，而且還有更好的性能炼彪，因?yàn)镃ore Animation 是在單獨(dú)的線程中完成的，不會(huì)阻塞主線程正歼，而且只會(huì)重繪界面上變化的部分（局部刷新）辐马。

2.分類

基礎(chǔ)動(dòng)畫(huà)缕减、關(guān)鍵幀動(dòng)畫(huà)都屬于屬性動(dòng)畫(huà)雷客，是通過(guò)修改屬性值產(chǎn)生動(dòng)畫(huà)效果，只需要設(shè)置初始值和結(jié)束值桥狡，中間的過(guò)程動(dòng)畫(huà)（“補(bǔ)間動(dòng)畫(huà)”）是由系統(tǒng)自動(dòng)計(jì)算產(chǎn)生搅裙。和基礎(chǔ)動(dòng)畫(huà)不同的是關(guān)鍵幀動(dòng)畫(huà)可以設(shè)置多個(gè)屬性值，每?jī)蓚€(gè)屬性中間的補(bǔ)間動(dòng)畫(huà)由系統(tǒng)自動(dòng)完成裹芝，基礎(chǔ)動(dòng)畫(huà)也可以看成是有兩個(gè)關(guān)鍵幀的關(guān)鍵幀動(dòng)畫(huà)部逮。

二、使用

1. CAAnimation

CAAnimation 是基類嫂易，其屬性它的子類也擁有兄朋。它不能直接使用。

代理方法 : 給NSObject添加了分類笨使，所以任何對(duì)象，都可以成為CAAnimation的代理僚害。

動(dòng)畫(huà)開(kāi)始的時(shí)候調(diào)用 - (void)animationDidStart:(CAAnimation *)anim;
動(dòng)畫(huà)停止的時(shí)候調(diào)用 - (void)animationDidStop:(CAAnimation *)anim finished:(BOOL)flag;

2.CAPropertyAnimation

位移動(dòng)畫(huà)通常使用屬性動(dòng)畫(huà)控制 CALayer 的 position 屬性持續(xù)改變糠悯，如果要實(shí)現(xiàn) CALayer 的旋轉(zhuǎn)帮坚、縮放等動(dòng)畫(huà)效果，若在平面上（二維空間）上互艾，則修改 CALayer 的 affineTransform 屬性试和，該屬性值為一個(gè)CGAffineTransform 對(duì)象；若在三維空間上纫普，則修改 CALayer 的 transform 屬性阅悍，該屬性值為一個(gè) CATransform3D 對(duì)象。

CATransform3D : 三維變換矩陣

3.CABasicAnimation 和 CAKeyframeAnimation

CAPropertyAnimation的子類，首先創(chuàng)建初始化一個(gè)CALayer事甜，初始化動(dòng)畫(huà)CABasicAnimation是設(shè)置 fromValue 和 toValue 谬泌，CAKeyframeAnimation是設(shè)置 values ，再設(shè)置其他動(dòng)畫(huà)屬性逻谦，將動(dòng)畫(huà)添加到圖層上掌实。

CALayer 為動(dòng)畫(huà)提供的方法

① 位移動(dòng)畫(huà)
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"];    

通過(guò)描繪路徑進(jìn)行關(guān)鍵幀動(dòng)畫(huà)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 旋轉(zhuǎn)動(dòng)畫(huà)
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 縮放動(dòng)畫(huà)
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 動(dòng)畫(huà)組
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 動(dòng)畫(huà)暫停

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

⑤ 動(dòng)畫(huà)恢復(fù)

-(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屬性用于控制動(dòng)畫(huà)類型邦马，還有私有動(dòng)畫(huà)贱鼻。

值| 說(shuō)明 |是否支持方向設(shè)置
-----|-----
kCATransitionFade|通過(guò)漸隱效果過(guò)渡宴卖，默認(rèn)屬性值|是
kCATransitionMoveIn|通過(guò)移入動(dòng)畫(huà)過(guò)渡，新視圖移到舊視圖上面|是
kCATransitionPush|通過(guò)推入動(dòng)畫(huà)過(guò)渡邻悬，新視圖把舊視圖推出去|是
kCATransitionReveal|通過(guò)揭開(kāi)動(dòng)畫(huà)過(guò)渡症昏，將舊視圖移開(kāi),同時(shí)顯示下面的新視圖|是
@"cube"|通過(guò)立方體旋轉(zhuǎn)動(dòng)畫(huà)過(guò)渡|是
@"oglFlip"|通過(guò)翻轉(zhuǎn)動(dòng)畫(huà)過(guò)渡|是
@"suckEffect"|通過(guò)收縮（吸入）動(dòng)畫(huà)過(guò)渡|否
@"rippleEffect"|通過(guò)水波動(dòng)畫(huà)過(guò)渡|否
@"pageCurl"|通過(guò)向后翻頁(yè)動(dòng)畫(huà)過(guò)渡|是
@"pageUnCurl"|通過(guò)向前翻頁(yè)動(dòng)畫(huà)過(guò)渡|是
@"cameraIrisHollowOpen"|通過(guò)相機(jī)鏡頭打開(kāi)效果動(dòng)畫(huà)過(guò)渡|否
@"cameraIrisHollowClose"|通過(guò)相機(jī)鏡頭關(guān)閉效果動(dòng)畫(huà)過(guò)渡|否

CATransition的subtype屬性用于控制動(dòng)畫(huà)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 = @"轉(zhuǎn)場(chǎng)";
    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.逐幀動(dòng)畫(huà)

通過(guò)設(shè)置UIImageView的animationImages屬性，然后調(diào)用它的startAnimating方法去播放一組逐幀圖片父丰，但是它存在著很大的性能問(wèn)題肝谭，并且這種方法一旦設(shè)置完圖片中間的過(guò)程就無(wú)法控制了。使用CADisplayLink加入到主循環(huán)隊(duì)列中础米，循環(huán)調(diào)用目標(biāo)方法分苇，在這個(gè)方法中更新視圖內(nèi)容就可以完成逐幀動(dòng)畫(huà)。

- (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的方式加載圖片會(huì)有緩存屁桑，使得占用的內(nèi)存很大
        //[pictArray addObject:[UIImage imageNamed:pictNum]];
    
        // 直接從文件中讀取圖片就不會(huì)占用太大的內(nèi)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動(dòng)畫(huà)封裝

UIView本身對(duì)于基本動(dòng)畫(huà)和關(guān)鍵幀動(dòng)畫(huà)医寿、轉(zhuǎn)場(chǎng)動(dòng)畫(huà)都有相應(yīng)的封裝。

動(dòng)畫(huà)使用block方式

UIViewAnimationCurve

UIViewAnimationOptions

UIViewKeyframeAnimationOptions
其中一部分值和 UIViewAnimationOptions 是一樣的，不一樣的如下：

7.彈簧動(dòng)畫(huà)

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