iOS中的动画有两种实现方式，一种是UIView来实现动画，另一种动画是通过CALayer来实现，下面介绍两种动画的简单实现：
一、UIView动画的实现
UIView使用Context来实现动画
关键代码：
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//参数1 动画名称 参数2 要实现动画的对象上下文 [UIView beginAnimations:@"attribute" context:_showImageView]; //设置动画的时间 [UIView setAnimationDuration:1.0f]; //设置动画延迟时间// [UIView setAnimationDelay:2]; //设置视图center 实现试图移动动画 _showImageView.center = CGPointMake(100, 100); //设置alpha值:视图透明度 _showImageView.alpha = 0.2f; //设置背景颜色 _showImageView.backgroundColor = [UIColor greenColor]; //UIView动画 设置代理 [UIView setAnimationDelegate:self]; //动画将要开始代理方法 [UIView setAnimationWillStartSelector:@selector(animationWillStart:context:)]; //动画已经结束代理方法 [UIView setAnimationDidStopSelector:@selector(animationDidStop:finished:context:)]; //提交动画设置，执行动画 [UIView commitAnimations]; |
使用Block实现的动画：
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//UIView动画， 使用Block实现 [UIView animateWithDuration:1.0f animations:^{ //通过设置translation 实现视图的偏移 if ([self.mySwitch isOn]) { //基于上一次的translation _showImageView.transform = CGAffineTransformTranslate(_showImageView.transform, 50, 0); } else { //基于原始的translation _showImageView.transform = CGAffineTransformMakeTranslation(-50, 0); } }]; |
二、CALayer动画的实现
CABasic动画的实现：根据初始位置和结束位置确定动画
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//CABasic 有两个属性 fromValue 动画开始值，toValue动画结束值 CABasicAnimation *animation1 = [CABasicAnimation animationWithKeyPath:@"position"]; [animation1 setDuration:2]; animation1.fromValue = [NSValue valueWithCGPoint:CGPointMake(150, 150)]; animation1.toValue = [NSValue valueWithCGPoint:CGPointMake(200, 200)]; [_imageView.layer addAnimation:animation1 forKey:@"position"]; |
创建一组动画：
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//创建组动画对象 CAAnimationGroup *group = [CAAnimationGroup animation]; //CABasic动画 CABasicAnimation *animation1 = [CABasicAnimation animationWithKeyPath:@"transform.scale.y"]; animation1.fromValue = @1.5; animation1.toValue = @0.5; //关键帧动画 CAKeyframeAnimation *animation2 = [CAKeyframeAnimation animationWithKeyPath:@"position"]; animation2.values = @[[NSValue valueWithCGPoint:CGPointMake(100, 100)], [NSValue valueWithCGPoint:CGPointMake(200, 150)], [NSValue valueWithCGPoint:CGPointMake(100, 200)], [NSValue valueWithCGPoint:CGPointMake(200, 250)]]; //group添加动画数组，group中动画对象并发执行 [group setAnimations:@[animation1, animation2]]; [group setDuration:4.0f]; [_imageView.layer addAnimation:group forKey:@"group"]; |