1蒸甜、UIView和核心動(dòng)畫區(qū)別?

核心動(dòng)畫只能添加到CALayer仰担， 核心動(dòng)畫一切都是假象骇径，并不會(huì)改變真實(shí)的值米间。如果需要與用戶交互就使用UIView的動(dòng)畫. 不需要與用戶交互可以使用核心動(dòng)畫。
在轉(zhuǎn)場(chǎng)動(dòng)畫中栅隐，核心動(dòng)畫的類型比較多塔嬉。根據(jù)?個(gè)路徑做動(dòng)畫玩徊，只能用核心動(dòng)畫(幀動(dòng)畫) 、動(dòng)畫組:同時(shí)做多個(gè)動(dòng)畫谨究。

2恩袱、核心動(dòng)畫的分類

核心動(dòng)畫繼承結(jié)構(gòu)
圖中的黑色虛線代表“繼承”某個(gè)類，紅色虛線代表“遵守”某個(gè)協(xié)議

2-1.png

2.1 CAAnimation

CAAnimation是所有動(dòng)畫對(duì)象的父類胶哲，負(fù)責(zé)控制動(dòng)畫的持續(xù)時(shí)間和速度畔塔，是個(gè)抽象類，不能直接使用鸯屿，應(yīng)該使用它具體的子類

屬性解讀

fillMode屬性值（要想fillMode有效铅歼，最好設(shè)置removedOnCompletion = NO）
kCAFillModeRemoved這個(gè)是默認(rèn)值公壤，也就是說當(dāng)動(dòng)畫開始前和動(dòng)畫結(jié)束后，動(dòng)畫對(duì)layer都沒有影響椎椰，動(dòng)畫結(jié)束后厦幅，layer會(huì)恢復(fù)到之前的狀態(tài)
CAFillModeForwards 當(dāng)動(dòng)畫結(jié)束后，layer會(huì)一直保持著動(dòng)畫最后的狀態(tài)
kCAFillModeBackwards 在動(dòng)畫開始前慨飘，只需要將動(dòng)畫加入了一個(gè)layer确憨，layer便立即進(jìn)入動(dòng)畫的初始狀態(tài)并等待動(dòng)畫開始。
kCAFillModeBoth這個(gè)其實(shí)就是上面兩個(gè)的合成.動(dòng)畫加入后開始之前瓤的，layer便處于動(dòng)畫初始狀態(tài)休弃，動(dòng)畫結(jié)束后layer保持動(dòng)畫最后的狀態(tài)

速度控制函數(shù)(CAMediaTimingFunction)
kCAMediaTimingFunctionLinear（線性）：勻速，給你一個(gè)相對(duì)靜態(tài)的感覺
kCAMediaTimingFunctionEaseIn（漸進(jìn)）：動(dòng)畫緩慢進(jìn)入圈膏，然后加速離開
kCAMediaTimingFunctionEaseOut（漸出）：動(dòng)畫全速進(jìn)入塔猾，然后減速的到達(dá)目的地
kCAMediaTimingFunctionEaseInEaseOut（漸進(jìn)漸出）：動(dòng)畫緩慢的進(jìn)入，中間加速稽坤，然后減速的到達(dá)目的地丈甸。這個(gè)是默認(rèn)的動(dòng)畫行為糯俗。

• delegate：動(dòng)畫代理

  @protocol CAAnimationDelegate <NSObject>
  @optional
  
  /* Called when the animation begins its active duration. */
  
  - (void)animationDidStart:(CAAnimation *)anim;
  
  /* Called when the animation either completes its active duration or
  * is removed from the object it is attached to (i.e. the layer). 'flag'
  * is true if the animation reached the end of its active duration
  * without being removed. */
  
  - (void)animationDidStop:(CAAnimation *)anim finished:(BOOL)flag;
  
  @end
  

• CALayer上動(dòng)畫的暫停和恢復(fù)

   //暫停動(dòng)畫
   - (void)pauseLayerAnimation:(CALayer *)layer {
       CFTimeInterval pauseTimes = [layer convertTime:CACurrentMediaTime()  fromLayer:nil];
    // speed動(dòng)畫的運(yùn)行速度，當(dāng)為0時(shí)會(huì)停止動(dòng)畫睦擂，speed越大說明動(dòng)畫執(zhí)行速度越快
       layer.speed = 0.0;
   // 讓layer的時(shí)間停留在pauseTimes
   // 動(dòng)畫的時(shí)間偏移得湘，也就是上次動(dòng)畫的暫停/繼續(xù) 距離本次動(dòng)畫的繼續(xù)/暫停的時(shí)間差
       layer.timeOffset = pauseTimes;
       NSLog(@":pauseTimes:%f", pauseTimes);
  }
  //恢復(fù)動(dòng)畫
   - (void)resumeLayerAnimation:(CALayer *)layer {
       CFTimeInterval pauseTimes = layer.timeOffset;
       //讓CALayer的時(shí)間繼續(xù)行走
        layer.speed = 1;
     // 取消上次記錄的停留時(shí)刻
        layer.timeOffset = 0.0;
     //取消上次設(shè)置的時(shí)間
        layer.beginTime = 0.0;
        CFTimeInterval timeSincePause = CACurrentMediaTime()-pauseTimes;
        layer.beginTime = timeSincePause;
        NSLog(@":timeSincePause:%f", timeSincePause);
  }
  

2.2 CAPropertyAnimation

CAPropertyAnimation也是一個(gè)抽象類，自身并不能對(duì)layer進(jìn)行動(dòng)畫操作祈匙，需要其子類CABasicAnimation和CAKeyframeAnimation來實(shí)現(xiàn)動(dòng)畫操作忽刽。

屬性解讀

2.3 CABasicAnimation——基本動(dòng)畫

基本動(dòng)畫斑唬，是CAPropertyAnimation的子類

動(dòng)畫過程說明：
隨著動(dòng)畫的進(jìn)行恕刘，在長(zhǎng)度為duration的持續(xù)時(shí)間內(nèi)缤谎，keyPath相應(yīng)屬性的值從fromValue漸漸地變?yōu)閠oValue
keyPath內(nèi)容是CALayer的可動(dòng)畫Animatable屬性
如果fillMode==kCAFillModeForwards同時(shí)removedOnComletion=NO，那么在動(dòng)畫執(zhí)行完畢后褐着，圖層會(huì)保持顯示動(dòng)畫執(zhí)行后的狀態(tài)坷澡。但在實(shí)質(zhì)上，圖層的屬性值還是動(dòng)畫執(zhí)行前的初始值含蓉，并沒有真正被改變频敛。

    CABasicAnimation *basicAnim = [CABasicAnimation animation];
    
    basicAnim.keyPath = @"position.y";
    basicAnim.fromValue = @(self.redView.layer.position.y);
    basicAnim.toValue = @(self.redView.layer.position.y + 300);
    
    basicAnim.duration = 2.0;
    // 動(dòng)畫完成時(shí)不移除動(dòng)畫
    basicAnim.removedOnCompletion = NO;
    // 動(dòng)畫完成時(shí)保持最后的狀態(tài)
    basicAnim.fillMode = kCAFillModeForwards;
    // 動(dòng)畫重復(fù)次數(shù)
    basicAnim.repeatCount = MAXFLOAT;
    // 自動(dòng)返轉(zhuǎn)（怎么去，怎么返回）
    basicAnim.autoreverses = YES;
    // 延遲2S開始動(dòng)畫
    basicAnim.beginTime = CACurrentMediaTime()+2;
    [self.redView.layer addAnimation:basicAnim forKey:nil];

2.3 CAKeyframeAnimation——關(guān)鍵幀動(dòng)畫

關(guān)鍵幀動(dòng)畫馅扣，也是CAPropertyAnimation的子類斟赚，與CABasicAnimation的區(qū)別是：
CABasicAnimation:只能從一個(gè)數(shù)值（fromValue）變到另一個(gè)數(shù)值（toValue）
CAKeyframeAnimation:會(huì)使用一個(gè)NSArray保存這些數(shù)值。

    UIBezierPath *path = [UIBezierPath bezierPathWithArcCenter:self.iconImageView.center radius:100 startAngle:0 endAngle:M_PI clockwise:YES];
    
    CAKeyframeAnimation *keyFrameAnima = [CAKeyframeAnimation animation];
    keyFrameAnima.path = path.CGPath;
    
    keyFrameAnima.keyPath = @"position";
    keyFrameAnima.duration = 2;
    keyFrameAnima.repeatCount = MAXFLOAT;
    keyFrameAnima.autoreverses = YES;
    [self.iconImageView.layer addAnimation:keyFrameAnima forKey:nil];

2.4 CAAnimationGroup——?jiǎng)赢嫿M

動(dòng)畫組掌腰，是CAAnimation的子類狰住，可以保存一組動(dòng)畫對(duì)象，將CAAnimationGroup對(duì)象加入層后齿梁，組中所有動(dòng)畫對(duì)象可以同時(shí)并發(fā)運(yùn)行

- (void)addAnimationGrounp {
    // 創(chuàng)建一個(gè)基礎(chǔ)動(dòng)畫
    CABasicAnimation *basicAnima = [CABasicAnimation animation];
    basicAnima.keyPath = @"transform.scale";
    basicAnima.fromValue = @1.0;
    basicAnima.toValue = @0;
    
    // 創(chuàng)建一個(gè)幀動(dòng)畫
    CAKeyframeAnimation *keyframeAnim = [CAKeyframeAnimation animation];
    keyframeAnim.path = [UIBezierPath bezierPathWithArcCenter:CGPointMake(170, self.redView.center.y) radius:100 startAngle:M_PI endAngle:M_PI*2 clockwise:YES].CGPath;
    keyframeAnim.keyPath = @"position";
    
    // 動(dòng)畫組
    CAAnimationGroup *animGroup = [CAAnimationGroup animation];
    animGroup.animations = @[basicAnima,keyframeAnim];
    animGroup.duration = 2.0;
    animGroup.repeatCount = MAXFLOAT;
    animGroup.autoreverses = YES;
    [self.redView.layer addAnimation:animGroup forKey:nil];
}

2.4 CATransition——轉(zhuǎn)場(chǎng)動(dòng)畫

CATransition是CAAnimation的子類创南，用于做轉(zhuǎn)場(chǎng)動(dòng)畫，能夠?yàn)閷犹峁┮瞥銎聊缓鸵迫肫聊坏膭?dòng)畫效果省核。UINavigationController就是通過CATransition實(shí)現(xiàn)了將控制器的視圖推入屏幕的動(dòng)畫效果稿辙。
注意：如果父視圖中的兩個(gè)子視圖互相切換，轉(zhuǎn)場(chǎng)動(dòng)畫應(yīng)加給父視圖气忠！

使用以下public api邻储，如果用了私有api可能會(huì)導(dǎo)致上架問題
//-----------------------------public api------------------------------------
/*
type:
kCATransitionFade; //淡入淡出
kCATransitionMoveIn; //覆蓋
kCATransitionPush; //推擠
kCATransitionReveal; //揭開
/
/
subType:
kCATransitionFromRight;
kCATransitionFromLeft;
kCATransitionFromTop;
kCATransitionFromBottom;
*/

    CATransition *transiont = [CATransition animation];
    /**
     fade ,                   //淡入淡出
     push,                       //推擠
     reveal,                     //揭開
     moveIn,                     //覆蓋
     cube,                       //立方體
     suckEffect,                 //吮吸
     oglFlip,                    //翻轉(zhuǎn)
     rippleEffect,               //波紋(水滴)
     pageCurl,                   //翻頁
     pageUnCurl,                 //反翻頁
     cameraIrisHollowOpen,       //開鏡頭
     cameraIrisHollowClose,      //關(guān)鏡頭
     */
    transiont.type =@"pageCurl";
    transiont.subtype = @"fromBottom";
    transiont.duration = 0.5;
    
    // 動(dòng)畫從哪個(gè)點(diǎn)開始
    transiont.startProgress = 0;
    // 動(dòng)畫到哪個(gè)點(diǎn)結(jié)束
    transiont.endProgress = 0.5;
  
    [self.imageView.layer addAnimation:transiont forKey:nil];

2.5 CASpringAnimation——彈性動(dòng)畫

彈性動(dòng)畫，是CABasicAnimation的子類

    CASpringAnimation *springAnimation = [CASpringAnimation animationWithKeyPath:@"bounds"];
    springAnimation.mass = 1;
    springAnimation.stiffness = 1000;
    springAnimation.damping = 20;
    springAnimation.initialVelocity = 50;
    springAnimation.duration = springAnimation.settlingDuration;
    springAnimation.fromValue = @(self.animationView.bounds);
    CGRect newBounds = CGRectMake(self.animationView.bounds.origin.x, self.animationView.bounds.origin.y, self.animationView.bounds.size.width+80, self.animationView.bounds.size.height);
    springAnimation.toValue = @(newBounds);
    springAnimation.fillMode = kCAFillModeForwards;
    springAnimation.removedOnCompletion = NO;
    springAnimation.timingFunction = [CAMediaTimingFunction functionWithName:kCAMediaTimingFunctionEaseInEaseOut];
    [self.animationView.layer addAnimation:springAnimation forKey:nil];