如何讓UIVisualEffectView淡入動畫？

Question

我有一個觀點，我想用一個模糊來遮擋它，並讓它具有動畫效果。我在故事板中添加了名爲blurField的UIVisualEffectView。這是我一起入侵的，有沒有更乾淨的方法來做到這一點？謝謝！

-(void)viewDidLoad { 
    [super viewDidLoad]; 
    self.blurField.alpha = 0.0; 
    [self performSelector:@selector(fillInBlur) withObject:nil afterDelay:3.0]; 
} 

-(void)fillInBlur { 
    self.blurField.alpha = 0.1; 
    [self performSelector:@selector(fillInBlur1) withObject:nil afterDelay:0.03]; 
} 

-(void)fillInBlur1 { 
    self.blurField.alpha = 0.2; 
    [self performSelector:@selector(fillInBlur2) withObject:nil afterDelay:0.03]; 
} 

-(void)fillInBlur2 { 
    self.blurField.alpha = 0.3; 
    [self performSelector:@selector(fillInBlur3) withObject:nil afterDelay:0.03]; 
} 

-(void)fillInBlur3 { 
    self.blurField.alpha = 0.4; 
    [self performSelector:@selector(fillInBlur4) withObject:nil afterDelay:0.03]; 
} 

-(void)fillInBlur4 { 
    self.blurField.alpha = 0.5; 
    [self performSelector:@selector(fillInBlur5) withObject:nil afterDelay:0.03]; 
} 

-(void)fillInBlur5 { 
    self.blurField.alpha = 0.6; 
    [self performSelector:@selector(fillInBlur6) withObject:nil afterDelay:0.03]; 
} 

-(void)fillInBlur6 { 
    self.blurField.alpha = 0.7; 
    [self performSelector:@selector(fillInBlur7) withObject:nil afterDelay:0.03]; 
} 

-(void)fillInBlur7 { 
    self.blurField.alpha = 0.8; 
    [self performSelector:@selector(fillInBlur8) withObject:nil afterDelay:0.03]; 
} 

-(void)fillInBlur8 { 
    self.blurField.alpha = 0.9; 
    [self performSelector:@selector(fillInBlur9) withObject:nil afterDelay:0.03]; 
} 

-(void)fillInBlur9 { 
    self.blurField.alpha = 1.0; 
} 

Answer 1

在iOS 8中，視覺效果視圖不透明度的動畫是非法和不可能的。這是因爲其實施的特殊方式。

在iOS 9中，您可以直接爲模糊本身製作動畫。從UIVisualEffectView開始，其effect爲nil，然後將其effect設置爲animations:塊內的UIBlurEffect。模糊會將自身變爲現實。

仍然有一些限制，但運行時會打電話給你清楚，如果你打他們。有關此主題的WWDC 2015視頻很棒。