- (void)addPraiseAnimation {
UIImageView *imageView = [[UIImageView alloc]initWithFrame:CGRectMake(kUIScreenWidth-45, kUIScreenHeight/1.7-55-64, 25, 25)];
imageView.alpha = 0;
imageView.backgroundColor = [UIColor clearColor];
imageView.clipsToBounds = YES;
// 用0.2秒的时间将imageView的透明度变成1.0，同时将其放大1.3倍，再缩放至1.1倍，这里参数根据需求设置
[UIView animateWithDuration:0.2 animations:^{
imageView.alpha = 1.0;
imageView.frame = CGRectMake(kUIScreenWidth-45, kUIScreenHeight/1.7-55-64, 25, 25);
CGAffineTransform transFrom = CGAffineTransformMakeScale(1.3, 1.3);
imageView.transform = CGAffineTransformScale(transFrom, 1, 1);
}];
// imageView放到view上
[_imageView addSubview:imageView];
// 动画结束点的X值
CGFloat finishX = kUIScreenWidth-45;
// 动画结束点的Y值
CGFloat finishY = kUIScreenHeight/1.7-120-64;
// imageView在运动过程中的缩放比例
CGFloat scale = round(random() % 2) + 0.7;
// 生成一个作为速度参数的随机数
CGFloat speed = 1 / round(random() % 900) + 0.6;
// 动画执行时间
NSTimeInterval duration = 4 * speed;
// 开始动画
[UIView beginAnimations:nil context:nil];
// 设置动画时间
[UIView setAnimationDuration:duration];
// 图片名字
imageView.image = [UIImage imageNamed:@"icon_wxzx_love"];
// 设置imageView的结束frame
imageView.frame = CGRectMake( finishX, finishY, 25 * scale, 25 * scale);
// 设置渐渐消失的效果，这里的时间最好和动画时间一致
[UIView animateWithDuration:duration animations:^{
imageView.alpha = 0;
}];
// 设置动画代理
[UIView setAnimationDelegate:self];
[UIView commitAnimations];
}