直播间点赞动画
#pragma mark - 点赞动画
- (
void
)praiseAnimation {
UIImageView
*imageView = [[
UIImageView
alloc] init];
CGRect
frame =
self
.view.frame;
// 初始frame，即设置了动画的起点
imageView.frame =
CGRectMake
(frame.size.width -
40
, frame.size.height -
65
,
30
,
30
);
// 初始化imageView透明度为0
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
(frame.size.width -
40
, frame.size.height -
90
,
30
,
30
);
CGAffineTransform
transfrom =
CGAffineTransformMakeScale
(
1.3
,
1.3
);
imageView.transform =
CGAffineTransformScale
(transfrom,
1
,
1
);
}];
[
self
.view addSubview:imageView];
// 随机产生一个动画结束点的X值
CGFloat
finishX = frame.size.width - round(random() %
200
);
// 动画结束点的Y值
CGFloat
finishY =
200
;
// 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;
// 如果得到的时间是无穷大，就重新附一个值（这里要特别注意，请看下面的特别提醒）
if
(duration == INFINITY) duration =
2.412346
;
// 随机生成一个0~7的数，以便下面拼接图片名
int
imageName = round(random() %
8
);
// 开始动画
[
UIView
beginAnimations:nil context:(__bridge
void
*_Nullable)(imageView)];
// 设置动画时间
[
UIView
setAnimationDuration:duration];
// 拼接图片名字
imageView.image = [
UIImage
imageNamed:[
NSString
stringWithFormat:
@"good%d_30x30_.png"
,imageName]];
// 设置imageView的结束frame
imageView.frame =
CGRectMake
( finishX, finishY,
30
* scale,
30
* 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
;
}];
// 结束动画，调用onAnimationComplete:finished:context:函数
[
UIView
setAnimationDidStopSelector:
@selector
(onAnimationComplete:finished:context:)];
// 设置动画代理
[
UIView
setAnimationDelegate:
self
];
[
UIView
commitAnimations];
}
/// 动画完后销毁iamgeView
- (
void
)onAnimationComplete:(
NSString
*)animationID finished:(
NSNumber
*)finished context:(
void
*)context{
UIImageView
*imageView = (__bridge
UIImageView
*)(context);
[imageView removeFromSuperview];
imageView = nil;
}