从底部拉出一个view

#define SCREEN_WIDTH         ([[UIScreen mainScreen] bounds].size.width) #define SCREEN_HEIGHT        ([[UIScreen mainScreen] bounds].size.height) @property (nonatomic ,strong) UIView *deliverView;  //底部View@property (nonatomic ,strong) UIView *BGView;  //遮罩- (void)appearClick {  // ------全屏遮罩     self.BGView                 = [[UIView alloc] init];    self.BGView.frame = [[UIScreen mainScreen] bounds];    self.BGView.tag             = 100;    self.BGView.backgroundColor = [[UIColor blackColor] colorWithAlphaComponent:0.0];    self.BGView.opaque = NO;    //--UIWindow的优先级最高，Window包含了所有视图，在这之上添加视图，可以保证添加在最上面     UIWindow *appWindow = [[UIApplication sharedApplication] keyWindow];     [appWindow addSubview:self.BGView];         // ------给全屏遮罩添加的点击事件     UITapGestureRecognizer *gesture = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(exitClick)];     gesture.numberOfTapsRequired = 1;     gesture.cancelsTouchesInView = NO;     [self.BGView addGestureRecognizer:gesture];     [UIView animateWithDuration:0.3 animations:^{        self.BGView.backgroundColor = [[UIColor blackColor] colorWithAlphaComponent:0.2];     }];         // ------底部弹出的View     self.deliverView                 = [[UIView alloc] init];    self.deliverView.frame           = CGRectMake(0, SCREEN_WIDTH, SCREEN_WIDTH, SCREEN_WIDTH);    self.deliverView.backgroundColor = [UIColor whiteColor];     [appWindow addSubview:self.deliverView];         // ------View出现动画     self.deliverView.transform = CGAffineTransformMakeTranslation(0.01, SCREEN_HEIGHT);     [UIView animateWithDuration:0.3 animations:^{        self.deliverView.transform = CGAffineTransformMakeTranslation(0.01, 0.01);     }]; }/**  * 功能： View退出  */- (void)exitClick {    NSLog(@"====");     [UIView animateWithDuration:0.3 animations:^{        self.deliverView.transform = CGAffineTransformMakeTranslation(0.01, SCREEN_HEIGHT);        self.deliverView.alpha = 0.2;        self.BGView.alpha = 0;     } completion:^(BOOL finished) {         [self.BGView removeFromSuperview];         [self.deliverView removeFromSuperview];     }]; }