自定义UIButton Shape，不使用图像

问题描述

| 我想制作一个与UIBackBarButtonItem相似的UIButton（带有一个指向导航堆栈的左箭头。我希望这样做而不必使用图像，因为按钮可能会有所不同，具体取决于手机） \的方向。 有没有办法在代码中激活这种影响？我的想法是以某种方式使用按钮的CALayer。 谢谢！ 编辑 我正在尝试使用@Deepak的建议，但是遇到了问题。我希望按钮的右侧看起来像[UIBezierPath bezierPathWithRoundedRect：rect cornerRadius：4]，而左侧看起来像箭头。我尝试使用addQuadCurvetoPoint：controlPoint方法执行此操作。 我将矩形的角用作控制点，但是路径并不像我期望的那样弯曲。就像我只使用addLinetoPoint：方法一样，它仍然处于困境。我的代码如下。

float radius = 4.0;
UIBezierPath *path = [UIBezierPath bezierPath];

CGPoint startPoint = CGPointMake(rect.size.width/5.0,0);
CGPoint pointBeforetopCurve = CGPointMake(rect.size.width - radius,0);
CGPoint topRightCorner = CGPointMake(rect.size.width,0);
CGPoint pointAfterTopCurve = CGPointMake(rect.size.width,0.0-radius);

CGPoint pointBeforeBottomCurve = CGPointMake(rect.size.width,rect.size.height-radius);
CGPoint bottomrightCorner = CGPointMake(rect.size.width,rect.size.height);
CGPoint pointAfterBottomCurve = CGPointMake(rect.size.width - radius,rect.size.height);

CGPoint pointBeforeArrow = CGPointMake(rect.size.width/5.0,rect.size.height);
CGPoint arrowPoint = CGPointMake(0,rect.size.height/2.0);


[path movetoPoint:pointBeforetopCurve];
[path addQuadCurvetoPoint:pointAfterTopCurve controlPoint:topRightCorner];

[path addLinetoPoint:pointBeforeBottomCurve];
[path addQuadCurvetoPoint:pointAfterBottomCurve controlPoint:bottomrightCorner];


[path addLinetoPoint:pointBeforeArrow];
[path addLinetoPoint:arrowPoint];
[path addLinetoPoint:startPoint];

    

解决方法

        您可以使用

Quartz

进行此操作。您将需要子类

UIButton

并实现其

drawRect:

方法。您将必须定义路径并用渐变填充。 您还必须实现

hitTest:withEvent:

，因为它涉及非矩形形状。     ,        这为我解决了绘画上的困难

    float radius = 10.0;
UIBezierPath *path = [UIBezierPath bezierPath];

CGPoint startPoint = CGPointMake(rect.size.width/5.0,0);
CGPoint pointBeforeTopCurve = CGPointMake(rect.size.width - radius,0);
CGPoint topRightCorner = CGPointMake(rect.size.width,0.0);
CGPoint pointAfterTopCurve = CGPointMake(rect.size.width,radius);

CGPoint pointBeforeBottomCurve = CGPointMake(rect.size.width,rect.size.height-radius);
CGPoint bottomRightCorner = CGPointMake(rect.size.width,rect.size.height);
CGPoint pointAfterBottomCurve = CGPointMake(rect.size.width - radius,rect.size.height);

CGPoint pointBeforeArrow = CGPointMake(rect.size.width/5.0,rect.size.height);
CGPoint arrowPoint = CGPointMake(0.0,rect.size.height/2.0);


[path moveToPoint:pointBeforeTopCurve];
[path addQuadCurveToPoint:pointAfterTopCurve controlPoint:topRightCorner];

[path addLineToPoint:pointBeforeBottomCurve];
[path addQuadCurveToPoint:pointAfterBottomCurve controlPoint:bottomRightCorner];


[path addLineToPoint:pointBeforeArrow];
[path addLineToPoint:arrowPoint];
[path addLineToPoint:startPoint];


[path fill];