ios view 动画

https://www.jianshu.com/p/6e326068edeb

https://www.jianshu.com/p/5abc038e4d94

1、块方式：

- (IBAction)btnUnfold_youch:(id)sender {
    CGRect dragViewRect = self.dragView.frame;

    if (dragViewRect.origin.y + 30 <= self.tabBarController.tabBar.frame.origin.y) {
        dragViewRect.origin.y = self.tabBarController.tabBar.frame.origin.y - 30;
        [UIView animateWithDuration: 0.5 animations: ^{
            self.dragView.frame = dragViewRect;
        } completion: nil];
    }
    //[self changeFrame];
}

2、提交方式：

- (IBAction)btnUnfold_youch:(id)sender {
//    CGRect dragViewRect = self.dragView.frame;
//
//    if (dragViewRect.origin.y + 30 <= self.tabBarController.tabBar.frame.origin.y) {
//        dragViewRect.origin.y = self.tabBarController.tabBar.frame.origin.y - 30;
//        [UIView animateWithDuration: 0.5 animations: ^{
//            self.dragView.frame = dragViewRect;
//        } completion: nil];
//    }
    [self changeFrame];
}

- (void)changeFrame {
    CGRect dragViewRect = self.dragView.frame;
    if (dragViewRect.origin.y + 30 <= self.tabBarController.tabBar.frame.origin.y) {
        [UIView beginAnimations:@"FrameAni" context:nil];
        [UIView setAnimationDuration:0.5];
        [UIView setAnimationDelegate:self.dragView];
        [UIView setAnimationWillStartSelector:@selector(startAni:)];
        [UIView setAnimationDidStopSelector:@selector(stopAni:)];
        [UIView setAnimationRepeatCount:1];
        [UIView setAnimationCurve:UIViewAnimationCurveEaseInOut];
        dragViewRect.origin.y = self.tabBarController.tabBar.frame.origin.y - 30;
        self.dragView.frame = dragViewRect;
        [UIView commitAnimations];
    }
}

- (void)startAni:(NSString *)aniID {
    NSLog(@"%@ start",aniID);
}

- (void)stopAni:(NSString *)aniID {
    NSLog(@"%@ stop",aniID);
}