实现ios后台缩略图模糊的一种方法

附代码：

- (void)applicationWillResignActive:(UIApplication *)application

{    

   //盖上view

    UIView* view = [[UIViewalloc] initWithFrame:CGRectMake(0,0, 320, 568)];

   view.backgroundColor =[UIColor redColor];

   view.alpha = 0.5;

   view.tag = 1111;

   [[[UIApplicationsharedApplication] keyWindow] addSubview:view];

}

- (void)applicationDidBecomeActive:(UIApplication *)application

{    

    //移除

   NSArray* array =[[UIApplication sharedApplication]keyWindow].subviews;

   

    for(id view in array)

    {

       if([view isKindOfClass:[UIViewclass]])

       {

          UIView* myView =view;

          if (myView.tag ==1111)

          {

              [myViewremoveFromSuperview];

          }

       }

    }

 

}