ios - 如何在 CATextLayer 文本上添加边框轮廓描边和填充描边

Question

这是代码，

text1 =[[NSMutableAttributedString alloc]initWithAttributedString:t.string];
            NSDictionary* attributes = @{(NSString*)kCTStrokeWidthAttributeName: @(-slider.value),
                                         (NSString*)kCTStrokeColorAttributeName: (id)curruntColor ,
                                         (NSString*)kCTForegroundColorAttributeName:(id)(textView.textColor)};

            [text1 addAttributes:attributes range:NSMakeRange(0, text1.length)];
            text1=[self getScaledStringFrom:text1 withScale:1];
            t.string=text1;

滑块值是笔划的宽度，t.string 表示文本层字符串。谢谢