iOS實(shí)現(xiàn)點(diǎn)贊動(dòng)畫特效

更新時(shí)間：2021年01月29日 09:37:14 作者：mayifan_blog

這篇文章主要為大家詳細(xì)介紹了iOS實(shí)現(xiàn)點(diǎn)贊動(dòng)畫特效，文中示例代碼介紹的非常詳細(xì)，具有一定的參考價(jià)值，感興趣的小伙伴們可以參考一下

本文實(shí)例為大家分享了iOS實(shí)現(xiàn)點(diǎn)贊動(dòng)畫特效的具體代碼，供大家參考，具體內(nèi)容如下

動(dòng)畫的基本使用

動(dòng)畫的實(shí)現(xiàn)基本上是基于對(duì)View控件和View的layer屬性進(jìn)行操作，對(duì)視圖進(jìn)行移動(dòng)，尺寸變換，透明度變換，旋轉(zhuǎn)等一系列操作。

關(guān)鍵幀動(dòng)畫：

動(dòng)畫的實(shí)現(xiàn)可以分為兩個(gè)部分，一部分是規(guī)定動(dòng)畫的變化內(nèi)容，比如view需要把scale從0變化到1，這個(gè)數(shù)字是相對(duì)值，即從尺寸為0變化到正常尺寸。另一個(gè)部分是規(guī)定動(dòng)畫的漸變時(shí)間。這樣就實(shí)現(xiàn)了view在規(guī)定時(shí)間完成指定變化了，這個(gè)變化的過程也可以通過參數(shù)設(shè)置為非均勻變化的。上面的示例是關(guān)鍵幀動(dòng)畫的實(shí)現(xiàn)，實(shí)現(xiàn)的方式是把動(dòng)畫劃分為幾個(gè)部分，“第一幀”做一件事，“第二幀”再做另外一件事，這就使得變化連續(xù)且可控。Duration參數(shù)確定了時(shí)間，delay確定了延時(shí)多久執(zhí)行，options確定了關(guān)鍵幀動(dòng)畫布局子控件。completion的參數(shù)是一個(gè)block，其中的內(nèi)容是在內(nèi)容執(zhí)行結(jié)束后才調(diào)用。這里做了3幀，前兩幀做了尺寸變?yōu)?倍然后恢復(fù)，后一幀使得其隱藏。結(jié)束后會(huì)調(diào)用block使其移除。

[UIView animateKeyframesWithDuration:self.animationDurtion * 4 delay:0.0 options:UIViewKeyframeAnimationOptionLayoutSubviews animations:^{
   /*參數(shù)1:關(guān)鍵幀開始時(shí)間
    參數(shù)2:關(guān)鍵幀占用時(shí)間比例
    參數(shù)3:到達(dá)該關(guān)鍵幀時(shí)的屬性值 */
   [UIView addKeyframeWithRelativeStartTime:0.0 relativeDuration:0.5 * self.animationDurtion animations:^{
    giveLikeView.transform = CGAffineTransformMakeScale(3, 3);;
   }];
   [UIView addKeyframeWithRelativeStartTime:0.5 * self.animationDurtion relativeDuration:0.5 * self.animationDurtion animations:^{
    giveLikeView.transform = CGAffineTransformIdentity;
   }];
   [UIView addKeyframeWithRelativeStartTime:self.animationDurtion relativeDuration:self.animationDurtion * 3 animations:^{
    giveLikeView.alpha = 0;
   }];
  } completion:^(BOOL finished) {
   giveLikeView.hidden = YES;
   [giveLikeView removeFromSuperview];
  }];

CAShapeLayer和UIBezierPath：

當(dāng)不滿足于view的變化，還需要在view的表面繪制一些圖案，就要對(duì)layer進(jìn)行操作，layer可以理解為是view的表面，每個(gè)view都有l(wèi)ayer參數(shù)。UIBezierPath是貝塞爾曲線，它用于設(shè)置繪圖的路徑，沒有了它，layer的繪制也是無效的，因?yàn)闆]有邊界呀。
如下代碼繪制了一個(gè)圓形的曲線，設(shè)置了它的中心，半徑，起始終止角這些屬性。

UIBezierPath *bezierPath = [UIBezierPath bezierPathWithArcCenter:CGPointMake(giveLikeView.bounds.size.width/2, giveLikeView.bounds.size.height/2) radius:giveLikeView.bounds.size.width startAngle:-1.57 endAngle:-1.57+3.14*2 clockwise:YES];
 circleLayer.path = bezierPath.CGPath;
 [self.layer addSublayer:circleLayer];

在最后我們可以看到：circleLayer.path = bezierPath.CGPath; [self.layer addSublayer:circleLayer];
它的作用是設(shè)置layer的路徑，并把layer添加到view的表面。下面來看看layer的配置。
創(chuàng)建一個(gè)layer后設(shè)置它的frame和顏色以及邊界，線寬這些屬性。

CAShapeLayer *circleLayer = [[CAShapeLayer alloc] init];
circleLayer.frame = giveLikeView.frame;
circleLayer.fillColor = [UIColor clearColor].CGColor;
circleLayer.strokeColor = [UIColor redColor].CGColor;
circleLayer.lineWidth = 1;

幾處聯(lián)系：把貝塞爾曲線和layer聯(lián)系起來，把layer和view的layer聯(lián)系起來。

為layer加動(dòng)畫（動(dòng)畫組）：

先創(chuàng)建動(dòng)畫組CAAnimationGroup，它可以容納若干動(dòng)畫，然后創(chuàng)建若干CABasicAnimation基礎(chǔ)動(dòng)畫。分別設(shè)置屬性，動(dòng)畫組需要涉及的屬性有時(shí)間功能，kCAMediaTimingFunctionEaseIn表示逐漸加快，另外還有設(shè)置持續(xù)時(shí)間，設(shè)置kCAFillModeForwards表示動(dòng)畫在結(jié)束后會(huì)保持，removedOnCompletion = NO表示最后不移除。在基礎(chǔ)動(dòng)畫的設(shè)置中，一般設(shè)置在動(dòng)畫組中的起始時(shí)間和持續(xù)時(shí)間，還有參數(shù)的變化。最后的 group.animations = @[scaleAnimtion,widthStartAnimtion,widthEndAnimtion];[circleLayer addAnimation:group forKey:nil];
兩句表示在動(dòng)畫組中添加動(dòng)畫然后為layer添加動(dòng)畫組，這樣layer就有動(dòng)畫特效了。

//動(dòng)畫
CAAnimationGroup *group = [CAAnimationGroup animation];
 group.timingFunction = [CAMediaTimingFunction functionWithName:kCAMediaTimingFunctionEaseIn];
 NSTimeInterval groupInterval = self.animationDurtion * 0.8;
 group.duration = groupInterval;
 group.fillMode = kCAFillModeForwards;
 group.removedOnCompletion = NO;
 
CABasicAnimation * scaleAnimtion = [CABasicAnimation animationWithKeyPath:@"transform.scale"];
 scaleAnimtion.beginTime = 0;
 scaleAnimtion.duration = groupInterval * 0.8;
 scaleAnimtion.fromValue = @(0);
 scaleAnimtion.toValue = @(1);
 
CABasicAnimation * widthStartAnimtion = [CABasicAnimation animationWithKeyPath:@"lineWidth"];
 widthStartAnimtion.beginTime = 0;
 widthStartAnimtion.duration = groupInterval * 0.8;
 widthStartAnimtion.fromValue = @(1);
 widthStartAnimtion.toValue = @(2);
 
CABasicAnimation * widthEndAnimtion = [CABasicAnimation animationWithKeyPath:@"lineWidth"];
 widthEndAnimtion.beginTime = groupInterval * 0.8;
 widthEndAnimtion.duration = groupInterval * 0.2;
 widthEndAnimtion.fromValue = @(2);
 widthEndAnimtion.toValue = @(0);
 
 group.animations = @[scaleAnimtion,widthStartAnimtion,widthEndAnimtion];
 [circleLayer addAnimation:group forKey:nil];

點(diǎn)贊動(dòng)畫的實(shí)現(xiàn)原理

下面來介紹demo的實(shí)現(xiàn)原理。

controller的尺寸設(shè)置為全屏，在其上方也覆蓋一個(gè)全屏的view，再在view上添加點(diǎn)擊事件（手勢）。

- (void)addGesture
{
 UITapGestureRecognizer *tap = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(creatOneHeart:)];
 [self addGestureRecognizer:tap]; 
}

下面看看點(diǎn)擊后調(diào)用的方法：

這里每次點(diǎn)擊都會(huì)獲取點(diǎn)擊的位置然后去初始化一個(gè)愛心，這是異步任務(wù)，放在主隊(duì)列中執(zhí)行。

- (void)creatOneHeart:(UITapGestureRecognizer *)sender
{
 CGPoint point = [sender locationInView:self];
 dispatch_async(dispatch_get_main_queue(),^{
  [self initOneNewHeart:point];
 });
}

這段代碼創(chuàng)建了視圖對(duì)象，這里自然用到了事先創(chuàng)建好的心形圖片。這里把創(chuàng)建的imageview存到隊(duì)列，顯示到view上，最后調(diào)用likeAction:方法執(zhí)行動(dòng)畫。

- (UIImageView *)createGiveLikeView
{
 UIImageView *giveLikeView = [[UIImageView alloc] initWithFrame:CGRectMake(0, 0, 40, 40)];
 giveLikeView.backgroundColor = [UIColor clearColor];
 UIImage *image = [UIImage imageNamed:@"icon_home_like_after"];
 giveLikeView.userInteractionEnabled = YES;
 giveLikeView.tag = GiveType;
 giveLikeView.image = image;
 giveLikeView.hidden = NO;
 _giveLikeView = giveLikeView;
 return _giveLikeView;
}
- (void)initOneNewHeart:(CGPoint)point
{
 UIImageView *giveLikeView = [self createGiveLikeView];
 giveLikeView.center = point;
 [self.array addObject:giveLikeView];
 [self addSubview:giveLikeView];
 [self likeAction:giveLikeView];
}

我們看看giveLikeAction：這個(gè)方法，它包括執(zhí)行心形的變化動(dòng)畫和繪制六個(gè)輻射的三角形動(dòng)畫，還有輻散的圓的動(dòng)畫。

- (void)likeAction:(UIImageView *)giveLikeView
{
 [self giveLikeAction:giveLikeView];
}
- (void)giveLikeAction:(UIImageView *)giveLikeView
{
 [self animtionChangeLikeType:giveLikeView];
 [self createTrigonsAnimtion:giveLikeView];
 [self createCircleAnimation:giveLikeView];
}

接下來直接看看輻散的三角形的動(dòng)畫（愛心的變化動(dòng)畫在上面已經(jīng)涉及到了）：
這段代碼跑了6個(gè)循環(huán)，做了6個(gè)三角形，它們分別有動(dòng)畫效果。
shape.transform = CATransform3DMakeRotation(3.14 / 3 * i, 0, 0, 1);實(shí)現(xiàn)了旋轉(zhuǎn)。
[giveLikeView.layer addSublayer:shape];執(zhí)行l(wèi)ayer的添加。
因?yàn)樵谘h(huán)中，每個(gè)layer都有獨(dú)立的動(dòng)畫，動(dòng)畫組實(shí)現(xiàn)的效果是三角形從小變大，最后變成一條直線并消失。
下面的兩行代碼用到了__bridge，它的作用是實(shí)現(xiàn)類型的轉(zhuǎn)換，這里把CGPathRef類型“橋接”轉(zhuǎn)化為了id類型，如果沒有它，會(huì)報(bào)錯(cuò)。
pathAnimation.fromValue = (__bridge id)startPath.CGPath;
pathAnimation.toValue = (__bridge id)endPath.CGPath;

- (void)createTrigonsAnimtion:(UIImageView *)giveLikeView
{
 for(int i=0;i<6;i++) {
  //創(chuàng)建一個(gè)layer并設(shè)置位置和填充色
  CAShapeLayer *shape = [[CAShapeLayer alloc] init];
  shape.position = CGPointMake(giveLikeView.bounds.size.width/2, giveLikeView.bounds.size.height/2);
  shape.fillColor = [UIColor redColor].CGColor;
  //設(shè)置貝塞爾曲線，執(zhí)行路徑
  UIBezierPath *startPath = [[UIBezierPath alloc] init];
  [startPath moveToPoint:CGPointMake(-2, 30)];
  [startPath addLineToPoint:CGPointMake(2, 30)];
  [startPath addLineToPoint:CGPointMake(0, 0)];
  [startPath addLineToPoint:CGPointMake(-2, 30)];
  shape.path = startPath.CGPath;
  
  //旋轉(zhuǎn)
  shape.transform = CATransform3DMakeRotation(3.14 / 3 * i, 0, 0, 1);
  [giveLikeView.layer addSublayer:shape];
  
  //動(dòng)畫組
  CAAnimationGroup *groupAnimation = [CAAnimationGroup animation];
  groupAnimation.timingFunction = [CAMediaTimingFunction functionWithName:kCAMediaTimingFunctionEaseIn];
  groupAnimation.duration = self.animationDurtion;
  groupAnimation.fillMode = kCAFillModeForwards;
  groupAnimation.removedOnCompletion = NO;
  
  //基礎(chǔ)動(dòng)畫1
  CABasicAnimation *scaleAnimtion = [CABasicAnimation animationWithKeyPath:@"transform.scale"];
  //縮放時(shí)間占20%
  scaleAnimtion.duration = self.animationDurtion * 0.2;
  scaleAnimtion.fromValue = @(0);
  scaleAnimtion.toValue = @(1);

  //繪制三角形結(jié)束 一條直線
  UIBezierPath *endPath = [UIBezierPath bezierPath];
  [endPath moveToPoint:CGPointMake(-2, 30)];
  [endPath addLineToPoint:CGPointMake(2, 30)];
  [endPath addLineToPoint:CGPointMake(0, 30)];

  //基礎(chǔ)動(dòng)畫2
  CABasicAnimation *pathAnimation = [CABasicAnimation animationWithKeyPath:@"path"];
  pathAnimation.beginTime = self.animationDurtion * 0.2;
  pathAnimation.duration = self.animationDurtion * 0.8;
  pathAnimation.fromValue = (__bridge id)startPath.CGPath;
  pathAnimation.toValue = (__bridge id)endPath.CGPath;

  groupAnimation.animations = @[scaleAnimtion,pathAnimation];
  [shape addAnimation:groupAnimation forKey:nil];
 }
}

demo實(shí)現(xiàn)的動(dòng)畫效果