推荐第三方库:
https://github.com/nicklockwood/FXBlurView
FXBlurView*Fx=[[FXBlurView alloc]initWithFrame:CGRectMake(0, 0, 375, 500)]; Fx.dynamic=YES; Fx.blurRadius=20.0; Fx.tintColor=[UIColor blackColor]; [self.view addSubview:Fx];
ios8后有相应的系统类和方法很简单如下
UIBlurEffect*effect=[UIBlurEffect effectWithStyle:UIBlurEffectStyleDark]; UIVisualEffectView*effectView=[[UIVisualEffectView alloc]initWithEffect:effect]; effectView.frame=CGRectMake(50, 350, 200, 200); [self.view addSubview:effectView];
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