获取CGContext绘制的Arc中的触摸点

时间:2012-05-04 08:01:03

标签: iphone objective-c cgcontext

我使用下面的代码绘制了很多弧:

CGContextAddArc(context,
                        e.x,
                        e.y,
                        Distance/2,
                        M_PI+angle1,
                        angle1,
                        aClock); 
        CGContextStrokePath(context)

现在我希望当我触摸任何拱形时,我想要检测哪个弧被触摸

我该怎么做?

1 个答案:

答案 0 :(得分:0)

你可以这样做:

1.将你的弧线加到一条路上,

_path = CGPathCreateMutable();
CGPathAddArc(_path, NULL, e.x, e.y, Distance/2, M_PI + angle1, angle1, aClock);
CGContextAddPath(context, _path);
CGContextStrokePath(context);

2.rewrite touchesBegan:withEvent:

-(void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event
{
    NSSet *allTouches = [event allTouches];
    UITouch *touch = [allTouches anyObject];
    CGPoint point = [touch locationInView:[touch view]];

    if (CGPathContainsPoint(_path, NULL, point, NO)) {
        NSLog(@"point:(%f, %f), Touch arc.", point.x, point.y);
    }
    else {
        NSLog(@"point:(%f, %f), Touch other.", point.x, point.y);
    }
}

你会看到“触控弧”。触摸弧时记录。