Objective c 显示"；截图快闪“；作为对用户的反馈

我对Objective-C非常陌生，刚刚从零开始制作了我的第一个应用程序。这是一个拼写应用程序，如果用户输入了错误的字母，我想在截图时显示屏幕上显示的白色闪光。我该怎么做呢？

一个简单的方法是在当前视图（或

UIWindow

）上设置一个白色

UIView

，alpha设置为0。然后，应用闪光效果，可以是这样的：

-(void)flashEffect {

   // Show it suddenly
   [self.flashSubview setAlpha:1.0];

   // Fade it out
   [UIView animateWithDuration:0.5 
                    animations:^{
                       [self.flashSubview setAlpha:0.0];
                    }
                    completion:^(BOOL finished){}];
}

---

在所有内容的顶部添加一个全屏白色

ui视图

，并设置其alpha动画

// Create a fullscreen, empty, white view and add it to the window.
UIWindow *window = [[UIApplication sharedApplication] keyWindow];
UIView *flashView = [[UIView alloc] initWithFrame:window.bounds];
flashView.backgroundColor = [UIColor whiteColor];
flashView.alpha = 1.0f;
[window addSubview:flashView];

// Fade it out and remove after animation.
[UIView animateWithDuration:0.05f animations:^{
    flashView.alpha = 0.0f;
} completion:^(BOOL finished) {
    [flashView removeFromSuperview];
}];

---

@鼓手感谢编辑和改进我的格式：-）这太完美了，谢谢：）

// Create a empty view with the color white.

UIView *flashView = [[UIView alloc] initWithFrame:window.bounds];
flashView.backgroundColor = [UIColor whiteColor];
flashView.alpha = 1.0;

// Add the flash view to the window

[window addSubview:flashView];

// Fade it out and remove after animation.

[UIView animateWithDuration:0.05 animations:^{     flashView.alpha = 0.0;    }      completion:^(BOOL finished) {    [flashView removeFromSuperview];     }     ];