代码语言：javascript复制
typedef NS_ENUM(NSInteger, UIBlurEffectStyle) {
UIBlurEffectStyleExtraLight,
UIBlurEffectStyleLight,
UIBlurEffectStyleDark
} NS_ENUM_AVAILABLE_IOS(8_0);
UIBlurEffect *blurEffect = [UIBlurEffect effectWithStyle:UIBlurEffectStyleDark];
UIVisualEffectView *blurEffectView = [[UIVisualEffectView alloc] initWithEffect:blurEffect];
blurEffectView.frame = self.imageView.bounds;
[self.imageView insertSubview:blurEffectView atIndex:0];
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