CAShapeLayer fillColor不呈現

Question

我有一個方法接受一個UIBezierPath作爲參數並相應地繪製一個形狀。如果我使用純色填充圖形，渲染效果會很好，但如果嘗試使其具有Alpha透明色，我首先會收到ARC警告，要求更改代碼並使用橋接，然後填充顏色根本不渲染。

這工作，但不是我想要的：

standShapeLayer.fillColor = [[UIColor redColor] CGColor]; 

這產生電弧警告「到C指針CGColorRef目標C指針類型的UIColor的隱式轉換」。

standShapeLayer.fillColor = [UIColor colorWithRed:0.2 green:0.66 blue:0.86 alpha:2.0f]; 

此運行，但沒有填充顏色應用於形狀：

standShapeLayer.fillColor = (__bridge CGColorRef)([UIColor colorWithRed:0.2 green:0.66 blue:0.86 alpha:2.0f]); 

下面是該方法的整個代碼：

-(void)drawShape:(UIBezierPath *)standShape { 

    [standShapeLayer removeFromSuperlayer]; 
    selectedStand = standShape; 
    standShapeLayer = [CAShapeLayer layer]; 
    standShapeLayer.path = standShape.CGPath; 
    standShapeLayer.fillColor = (__bridge CGColorRef)([UIColor colorWithRed:0.2 green:0.66 blue:0.86 alpha:2.0f]); 
    NSLog(@"color = %@", standShapeLayer.fillColor); // This logs the correct colour which is not rendered. 
    // standShapeLayer.fillColor = [[UIColor redColor] CGColor]; << This works but is not what I need. 
    standShapeLayer.strokeColor = [[UIColor redColor] CGColor]; 
    standShapeLayer.lineWidth = 2; 
    [_imageView.layer addSublayer:standShapeLayer]; 

} 

什麼我需要怎樣做才能讓顏色用alpha來填充CAShapeLayer形狀？

Answer 1

雖然我寫的我認爲是正確的，但顯然不是。

standShapeLayer.fillColor = [UIColor colorWithRed:0.2 green:0.66 blue:0.86 alpha:2.0f]; 

應該是：

[standShapeLayer setFillColor:[[UIColor colorWithRed:0.2 green:0.66 blue:0.86 alpha:2.0f] CGColor]]; 

Answer 2

你alpha不正確。

alpha - 顏色對象的不透明度值，從0.0到1.0指定爲值 。

試圖改變

standShapeLayer.fillColor = (__bridge CGColorRef)([UIColor colorWithRed:0.2 green:0.66 blue:0.86 alpha:2.0f]); 

到

standShapeLayer.fillColor = [[UIColor colorWithRed:0.2 green:0.66 blue:0.86 alpha:0.7f] CGColor];