这篇文章介绍UIBezierPath的详细的使用, 以及一些细节!
创建一个XTBezierPath继承于UIView的类 使用drawRect 完成图形的绘制
在drawRect方法完成绘制 使用 moveToPoint, addLineToPoint两个方法绘制一个任意多边形 其中w, h 代表自定义View的宽, 高 代码如下:
// 初始化一个UIBezierPath对象. UIBezierPath *bPath = [UIBezierPath bezierPath]; // 线宽. bPath.lineWidth = 10; // 拐点处理. bPath.lineCapStyle = kCGLineCapRound; // 终点处理. bPath.lineJoinStyle = kCGLineCapRound; // 添加线上的点. [bPath moveToPoint:CGPointMake(w / 2, 0.0)]; [bPath addLineToPoint:CGPointMake(w, h / 2)]; [bPath addLineToPoint:CGPointMake(w / 2, h)]; [bPath addLineToPoint:CGPointMake(0.0, h / 2)]; [bPath closePath]; // 填充内部颜色. // 绘制线. [bPath stroke];
任意多边形
绘制一个矩形, 直接使用bezierPathWithRect这个方法
// 创建矩形. UIBezierPath *bPath = [UIBezierPath bezierPathWithRect:CGRectMake(30, 30, w - 60, h - 60)]; bPath.lineWidth = 10; [bPath stroke];
矩形
绘制内切曲线, 直接使用这个方法bezierPathWithOvalInRect
// 这个方法, 是做一个内切曲线. // 圆形就是宽高相等. UIBezierPath *bPath = [UIBezierPath bezierPathWithOvalInRect:CGRectMake(5, 5, w - 10, h - 100)]; bPath.lineWidth = 10; [bPath stroke];
内切曲线
绘制一条弧线, bezierPathWithArcCenter这个方法
UIBezierPath *bPath = [UIBezierPath bezierPathWithArcCenter:CGPointMake(150, 150) radius:130 startAngle:0 endAngle:M_PI_2 clockwise:YES]; bPath.lineWidth = 10; [bPath stroke];
弧线
绘制二次贝塞尔曲线,moveToPoint, addQuadCurveToPoint这两个搭配使用
原理图
// 二次贝塞尔曲线的支持. UIBezierPath *bPath = [UIBezierPath bezierPath]; // 开始的点. [bPath moveToPoint:CGPointMake(0, h)]; // 终止点, 控制点. [bPath addQuadCurveToPoint:CGPointMake(w, h) controlPoint:CGPointMake(0, 0)]; [bPath fill];
贝塞尔曲线
绘制三次贝塞尔曲线, moveToPoint, addCurveToPoint
原理图
// 三次贝塞尔曲线 UIBezierPath *bPath = [UIBezierPath bezierPath]; [bPath moveToPoint:CGPointMake(0, h / 2)]; [bPath addCurveToPoint:CGPointMake(w, h / 2) controlPoint1:CGPointMake(w / 2, 0) controlPoint2:CGPointMake(w / 2, h)]; bPath.lineWidth = 10; [bPath stroke];
贝塞尔曲线
UIBezierPath类只是CGPathRef数据类型和path绘图属性的一个封装, 我们可以用来直接修改底层的path, 通过CGMutablePathRef, 1. 完全的使用Core Graphics函数去修改path
#if 0 CGMutablePathRef cgPath = CGPathCreateMutable(); CGPathAddEllipseInRect(cgPath, NULL, CGRectMake(0, 0, 300, 300)); CGPathAddEllipseInRect(cgPath, NULL, CGRectMake(50, 50, 200, 200)); // Now create the UIBezierPath object UIBezierPath* bPath = [UIBezierPath bezierPath]; bPath.CGPath = cgPath; bPath.usesEvenOddFillRule = YES; bPath.lineWidth = 5; // After assigning it to the UIBezierPath object, you can release // your CGPathRef data type safely. [bPath stroke]; CGPathRelease(cgPath); #endif // 2.搭配使用 UIBezierPath类拥有自己底层的CGPathRef data type, 所以需要使用一个副本来修改, 之后再赋值 #if 1 UIBezierPath *bPath = [UIBezierPath bezierPathWithOvalInRect:CGRectMake(0, 0, 300, 300)]; // Get the CGPathRef and create a mutable version. CGPathRef cgPath = bPath.CGPath; CGMutablePathRef mutablePath = CGPathCreateMutableCopy(cgPath); // Modify the path and assign it back to the UIBezierPath object CGPathAddEllipseInRect(mutablePath, NULL, CGRectMake(50, 50, 200, 200)); bPath.CGPath = mutablePath; // Release both the mutable copy of the path. bPath.lineWidth = 5; [[UIColor purpleColor] set]; [bPath stroke]; CGPathRelease(mutablePath); #endif
效果图
绘制一个圆, 同时画一个边框
// Create an oval shape to draw. UIBezierPath *bPath = [UIBezierPath bezierPathWithOvalInRect: CGRectMake(0, 0, 200, 200)]; // Set the render colors [[UIColor lightGrayColor] setStroke]; [[UIColor greenColor] setFill]; CGContextRef aRef = UIGraphicsGetCurrentContext(); // If you have content to draw after the shape, // save the current state before changing the transform //CGContextSaveGState(aRef); // Adjust the view's origin temporarily. The oval is // now drawn relative to the new origin point. CGContextTranslateCTM(aRef, 50, 50); // Adjust the drawing options as needed. bPath.lineWidth = 5; // Fill the path before stroking it so that the fill // color does not obscure the stroked line. [bPath fill]; [bPath stroke];
效果图
总结 : UIBezierPath 使用这个就可以完成多种演示的图形了.