获取当前屏幕显示的viewcontroller

//获取当前屏幕显示的viewcontroller 

- (UIViewController *)getCurrentVC 

{ 

    UIViewController *result = nil; 

       

    UIWindow * window = [[UIApplication sharedApplication] keyWindow]; 

    if (window.windowLevel != UIWindowLevelNormal) 

    { 

        NSArray *windows = [[UIApplication sharedApplication] windows]; 

        for(UIWindow * tmpWin in windows) 

        { 

            if (tmpWin.windowLevel == UIWindowLevelNormal) 

            { 

                window = tmpWin; 

                break; 

            } 

        } 

    } 

       

    UIView *frontView = [[window subviews] objectAtIndex:0]; 

    id nextResponder = [frontView nextResponder]; 

       

    if ([nextResponder isKindOfClass:[UIViewController class]]) 

        result = nextResponder; 

    else 

        result = window.rootViewController; 

       

    return result; 

}