iOS缩放动画 + 高度从无到有再到无动画

缩放动画

UILabel *tipLab=[[UILabel alloc]initWithFrame:CGRectMake(0, 70, kScreenW, 40)];         tipLab.textColor=[UIColor whiteColor];

tipLab.text=@"xxxx";

[self.viewaddSubview:tipLab];

self.tipLab=tipLab;

 tipLab.transform = CGAffineTransformMakeScale(1.0, 0.2);

 [UIView animateWithDuration:0.8 animations:^{

                tipLab.transform = CGAffineTransformMakeScale(1.0, 1.0);

    }completion:^(BOOLfinish){

               CFTimeInterval pausedTime = [tipLab.layer convertTime:CACurrentMediaTime() fromLayer:nil];

               //将动画暂停

               tipLab.layer.speed = 0;

                tipLab.layer.timeOffset = pausedTime;

                NSTimer *timer=[NSTimer scheduledTimerWithTimeInterval:3 target:self selector:@selector(updateTimer:) userInfo:nil repeats:NO];

                [[NSRunLoop currentRunLoop]addTimer:timer forMode:NSRunLoopCommonModes];

            }];

-(void)updateTimer:(NSTimer*)timer

{

    //让动画执行

    self.tipLab.layer.speed=1;

    //取消上次设置的时间

    self.tipLab.layer.beginTime = 0;

    //获取上次动画停留的时刻

    CFTimeInterval pauseTime = self.tipLab.layer.timeOffset;

    //取消上次记录的停留时刻

    self.tipLab.layer.timeOffset = 0;

    //计算暂停的时间，设置相对于父坐标系的开始时间

    self.tipLab.layer.beginTime = [self.tipLab.layer convertTime:CACurrentMediaTime() fromLayer:nil] - pauseTime;

    [UIView animateWithDuration:0.8 animations:^{

        self.tipLab.transform = CGAffineTransformMakeScale(1.0, 1.0);

    }completion:^(BOOLfinish){

        [UIView animateWithDuration:0.8 animations:^{

            self.tipLab.transform = CGAffineTransformMakeScale(1.0, 0.2);

        }completion:^(BOOLfinish){

            self.tipLab.transform = CGAffineTransformMakeScale(1.0, 0.0);

        }];

    }];

}

高度从无到有再到无动画

UILabel *tipLab=[[UILabel alloc]initWithFrame:CGRectMake(0, 70, kScreenW, 40)];         tipLab.textColor=[UIColor whiteColor];

tipLab.text=@"xxxx";

[self.viewaddSubview:tipLab];

self.tipLab.frame = CGRectMake(0, 70, kScreenW,0);

            [UIView animateWithDuration:0.8 animations:^{

                self.tipLab.frame=CGRectMake(0,70,kScreenW,40);

            }completion:^(BOOLfinish){

                NSTimer *timer=[NSTimer scheduledTimerWithTimeInterval:3 target:self selector:@selector(updateTimer:) userInfo:nil repeats:NO];

                [[NSRunLoop currentRunLoop]addTimer:timer forMode:NSRunLoopCommonModes];

            }];

-(void)updateTimer:(NSTimer*)timer

{

    [UIView animateWithDuration:0.8 animations:^{

        self.tipLab.frame=CGRectMake(0,70,kScreenW,0);

    }completion:^(BOOLfinish){

        [self removeTipLabel];

    }];

}

-(void)removeTipLabel

{

    if(self.tipLab) {

        [self.tipLab removeFromSuperview];

        self.tipLab=nil;

        [self.timerinvalidate];

        self.timer=nil;

    }

}