我试图得到一个类似Mac OS X的"语音泡泡"效果，当你右键点击 docker 上的某个东西时.以下是我现在拥有的:
我需要得到下半部分的"三角形"部分.有没有办法画出这样的东西，然后在周围画一个边界？这将是一个iPhone应用程序.
提前谢谢！
EDIT: Many thanks to Brad Larson, here's what it looks like now:
我试图得到一个类似Mac OS X的"语音泡泡"效果，当你右键点击 docker 上的某个东西时.以下是我现在拥有的:
我需要得到下半部分的"三角形"部分.有没有办法画出这样的东西，然后在周围画一个边界？这将是一个iPhone应用程序.
提前谢谢！
EDIT: Many thanks to Brad Larson, here's what it looks like now:
我以前确实画过这个形状(底部有一个三角形的圆角矩形).我使用的Quartz绘图代码如下:
CGRect currentFrame = self.bounds;
CGContextSetLineJoin(context, kCGLineJoinRound);
CGContextSetLineWidth(context, strokeWidth);
CGContextSetStrokeColorWithColor(context, [MyPopupLayer popupBorderColor]);
CGContextSetFillColorWithColor(context, [MyPopupLayer popupBackgroundColor]);
// Draw and fill the bubble
CGContextBeginPath(context);
CGContextMoveToPoint(context, borderRadius + strokeWidth + 0.5f, strokeWidth + HEIGHTOFPOPUPTRIANGLE + 0.5f);
CGContextAddLineToPoint(context, round(currentFrame.size.width / 2.0f - WIDTHOFPOPUPTRIANGLE / 2.0f) + 0.5f, HEIGHTOFPOPUPTRIANGLE + strokeWidth + 0.5f);
CGContextAddLineToPoint(context, round(currentFrame.size.width / 2.0f) + 0.5f, strokeWidth + 0.5f);
CGContextAddLineToPoint(context, round(currentFrame.size.width / 2.0f + WIDTHOFPOPUPTRIANGLE / 2.0f) + 0.5f, HEIGHTOFPOPUPTRIANGLE + strokeWidth + 0.5f);
CGContextAddArcToPoint(context, currentFrame.size.width - strokeWidth - 0.5f, strokeWidth + HEIGHTOFPOPUPTRIANGLE + 0.5f, currentFrame.size.width - strokeWidth - 0.5f, currentFrame.size.height - strokeWidth - 0.5f, borderRadius - strokeWidth);
CGContextAddArcToPoint(context, currentFrame.size.width - strokeWidth - 0.5f, currentFrame.size.height - strokeWidth - 0.5f, round(currentFrame.size.width / 2.0f + WIDTHOFPOPUPTRIANGLE / 2.0f) - strokeWidth + 0.5f, currentFrame.size.height - strokeWidth - 0.5f, borderRadius - strokeWidth);
CGContextAddArcToPoint(context, strokeWidth + 0.5f, currentFrame.size.height - strokeWidth - 0.5f, strokeWidth + 0.5f, HEIGHTOFPOPUPTRIANGLE + strokeWidth + 0.5f, borderRadius - strokeWidth);
CGContextAddArcToPoint(context, strokeWidth + 0.5f, strokeWidth + HEIGHTOFPOPUPTRIANGLE + 0.5f, currentFrame.size.width - strokeWidth - 0.5f, HEIGHTOFPOPUPTRIANGLE + strokeWidth + 0.5f, borderRadius - strokeWidth);
CGContextClosePath(context);
CGContextDrawPath(context, kCGPathFillStroke);
// Draw a clipping path for the fill
CGContextBeginPath(context);
CGContextMoveToPoint(context, borderRadius + strokeWidth + 0.5f, round((currentFrame.size.height + HEIGHTOFPOPUPTRIANGLE) * 0.50f) + 0.5f);
CGContextAddArcToPoint(context, currentFrame.size.width - strokeWidth - 0.5f, round((currentFrame.size.height + HEIGHTOFPOPUPTRIANGLE) * 0.50f) + 0.5f, currentFrame.size.width - strokeWidth - 0.5f, currentFrame.size.height - strokeWidth - 0.5f, borderRadius - strokeWidth);
CGContextAddArcToPoint(context, currentFrame.size.width - strokeWidth - 0.5f, currentFrame.size.height - strokeWidth - 0.5f, round(currentFrame.size.width / 2.0f + WIDTHOFPOPUPTRIANGLE / 2.0f) - strokeWidth + 0.5f, currentFrame.size.height - strokeWidth - 0.5f, borderRadius - strokeWidth);
CGContextAddArcToPoint(context, strokeWidth + 0.5f, currentFrame.size.height - strokeWidth - 0.5f, strokeWidth + 0.5f, HEIGHTOFPOPUPTRIANGLE + strokeWidth + 0.5f, borderRadius - strokeWidth);
CGContextAddArcToPoint(context, strokeWidth + 0.5f, round((currentFrame.size.height + HEIGHTOFPOPUPTRIANGLE) * 0.50f) + 0.5f, currentFrame.size.width - strokeWidth - 0.5f, round((currentFrame.size.height + HEIGHTOFPOPUPTRIANGLE) * 0.50f) + 0.5f, borderRadius - strokeWidth);
CGContextClosePath(context);
CGContextClip(context);
如果不打算使用比简单 colored颜色 更复杂的渐变或其他填充，可以省略末端的剪裁路径.