2019-03-11 iOS 窗口Window缩小动画（假象）

UIWindow *window = [UIApplication.sharedApplication keyWindow];

    UIView* shadowBack = [[UIView alloc]initWithFrame:window.bounds];

    shadowBack.backgroundColor = [UIColor blackColor];

    shadowBack.alpha=1.0;

    [window addSubview:shadowBack];

    NSTimeInterval timeInterval =0.35;

    UIView *snapView = [self.navigationController.view snapshotViewAfterScreenUpdates:NO];

    [window addSubview:snapView];

    [UIView animateWithDuration:timeInterval animations:^{

        snapView.transform = CGAffineTransformMakeScale(0.8, 0.8);

    }completion:^(BOOLfinished) {

        snapView.transform = CGAffineTransformMakeScale(0.8, 0.8);

    }];

    XDPayCommonView *payAlertView = [XDPayCommonView xd_getFromXib];

    [payAlertView showView:self.orderModel.totalAmount amount:@"0.0" WithCompletion:^(XDPayType payType) {

        [weakSelf payOrderWithType:payType];

    } withDismissComplection:^{

        [UIView animateWithDuration:timeInterval animations:^{

            snapView.transform = CGAffineTransformIdentity;

        }completion:^(BOOLfinished) {

            [snapView removeFromSuperview];

            [shadowBack removeFromSuperview];

        }];

    }];