最近在進行項目性能的優(yōu)化,遇到view圓角優(yōu)化的問題,有一些粗略的看法，現(xiàn)總結(jié)一下。
設(shè)置圓角目前知道的有四種方法：

• 1、通過shapeLayer設(shè)置
• 2、通過view的layer設(shè)置
• 3、通過BezierPath設(shè)置
• 4、通過貼圖的方式設(shè)置

shapeLayer的?實現(xiàn)

通過bezizerpath設(shè)置一個路徑，加到目標視圖的layer上。代碼如下：

 // 創(chuàng)建一個view
  UIView *showView = [[UIView alloc] initWithFrame:CGRectMake(100, 100, 100, 100)];
  [self.view addSubview:showView];
  showView.backgroundColor = [UIColor whiteColor];
  showView.alpha = 0.5;
    
   // 貝塞爾曲線(創(chuàng)建一個圓)
    UIBezierPath *path = [UIBezierPath     bezierPathWithArcCenter:CGPointMake(100 / 2.f, 100 / 2.f)
                                                        radius:100 / 2.f
                                                       startAngle:0 
                                                       endAngle:M_PI * 2
                                                      clockwise:YES];
    
      CAShapeLayer *layer = [CAShapeLayer layer];
      layer.frame = showView.bounds;
      layer.path = path.CGPath;
      [showView.layer addSublayer:layer];

view的layer的?實現(xiàn)

通過view的layer直接設(shè)置的方式，是所有的方法中最簡單的，代碼如下：

 - (UIImageView  *)avatarImage { 

     if (!_avatarImage) { 
        
        _avatarImage = [[UIImageView alloc] initWithFrame:CGRectMake(20,10, avatarDiameter, avatarDiameter)];
        _avatarImage.backgroundColor = [UIColor grayColor];
        _avatarImage.contentMode = UIViewContentModeScaleAspectFit;
        _avatarImage.layer.cornerRadius = avatarDiameter/2.0;
        _avatarImage.layer.masksToBounds = YES;
        [_avatarImage setImage:[UIImage imageNamed:@"test.jpg"]];
      }
    return _avatarImage;
}

BezierPath的?實現(xiàn)

BezierPath的實現(xiàn)方式繼承UIView，自己實現(xiàn)一個customview,代碼如下。

- (instancetype)initWithFrame:(CGRect)frame {
    
    if (self = [super initWithFrame:frame]) {
        
    }
    return self;
}
- (void)drawRect:(CGRect)rect { 
     // Drawing code 
    CGRect bounds = self.bounds;
    [[UIColor whiteColor] set];
    UIRectFill(bounds);

    [[UIBezierPath bezierPathWithRoundedRect:rect cornerRadius:CGRectGetWidth(bounds)/2.0] addClip];
    [self.image drawInRect:bounds];
} 

貼圖的?實現(xiàn)

貼圖的方式是使用一個中間是圓形鏤空的圖覆蓋在需要圓角化的圖片的上方。代碼如下：

- (instancetype)initWithStyle:(UITableViewCellStyle)style reuseIdentifier:(NSString *)reuseIdentifier {
    
     if (self = [super initWithStyle:style reuseIdentifier:reuseIdentifier]) {
        
         [self.contentView addSubview:self.avatarImage];
         [self.contentView addSubview:self.maskImage];
     }
     return self;
   }

- (UIImageView *)avatarImage {
    
     if (!_avatarImage) { 
        
        _avatarImage = [[UIImageView alloc] initWithFrame:CGRectMake(20,10, avatarDiameter, avatarDiameter)];
        _avatarImage.backgroundColor = [UIColor grayColor];
        _avatarImage.contentMode = UIViewContentModeScaleAspectFit;
         [_avatarImage setImage:[UIImage imageNamed:@"test.jpg"]];
     }
     return _avatarImage;
 }

 //中心鏤空的圖
 - (UIImageView *)maskImage {  
    
     if (!_maskImage) { 
        
       _maskImage = [[UIImageView alloc] initWithFrame:CGRectMake(20,10, avatarDiameter, avatarDiameter)]; 
        _maskImage.contentMode = UIViewContentModeScaleAspectFit; 
       [_maskImage setImage:[UIImage imageNamed:@"corner_circle.png"]]; 
     }
     return _maskImage;
} 

如果大家有什么新的方法，希望推薦給我。