5

我需要一些帮助来填补我的道路。例如，我不知道该放在哪里CGContextFillPath(path);。我对绘图（和 iOS 开发）还很陌生，现在我真的尝试了将近两个小时。但我到了不得不放弃的地步……希望你能对我的问题有所了解。我收到以下错误：invalid context 

-(CGMutablePathRef) drawHexagon:(CGPoint)origin
    {
        //create mutable path
        CGMutablePathRef path = CGPathCreateMutable();

        CGPathMoveToPoint(path, nil, origin.x, origin.y);

        CGPoint newloc = CGPointMake(origin.x - 20, origin.y + 42);
        CGPathMoveToPoint(path, NULL, newloc.x, newloc.y);
        CGPathAddLineToPoint(path, NULL, newloc.x + 16,newloc.y + 38);
        CGPathAddLineToPoint(path, NULL, newloc.x + 49, newloc.y + 0);
        CGPathAddLineToPoint(path, NULL, newloc.x + 23,  newloc.y - 39);
        CGPathAddLineToPoint(path, NULL, newloc.x - 25,newloc.y - 40);
        CGPathAddLineToPoint(path, NULL, newloc.x -43, newloc.y + 0);
        CGPathCloseSubpath(path);
        CGContextAddPath(context, path);
        context = UIGraphicsGetCurrentContext();
        CGContextSaveGState(context);
        CGContextSetLineWidth(context, 2.0);
        CGContextSetStrokeColorWithColor(context, [UIColor blueColor].CGColor);
        CGContextAddPath(context, path);
        CGContextStrokePath(context);
        CGContextSetFillColorWithColor(context, [UIColor redColor].CGColor);
        CGContextFillPath(path);



           return path;   

    }

    -(id) init
    {
        // always call "super" init
        // Apple recommends to re-assign "self" with the "super" return value
        if( (self=[super init])) {

           clickedHexagonsUpToNow = [[NSMutableArray alloc]init ];
            CGSize screenSize = [CCDirector sharedDirector].winSize;

            background = [CCSprite spriteWithFile:@"background.png"];
            background.anchorPoint= ccp(0,0);
            [self addChild:background z:-1 tag:0];

            hex1TouchArea = [self drawHexagon:ccp(82,120)];
            hex2TouchArea = [self drawHexagon:ccp(50,157)];
            hex3TouchArea = [self drawHexagon:ccp(220 ,196)];
            hex4TouchArea = [self drawHexagon:ccp(280,153)];
            hex5TouchArea = [self drawHexagon:ccp(84,118)];
            hex6TouchArea = [self drawHexagon:ccp(82,120)];
            hex7TouchArea = [self drawHexagon:ccp(82,120)];
            hex8TouchArea = [self drawHexagon:ccp(82,120)];
            hex9TouchArea = [self drawHexagon:ccp(82,120)];


             self.isTouchEnabled = YES;

            }
    return self;
}
4

2 回答 2

9

它应该以 CGContext 作为参数，而不是 CGPath。

CGContextFillPath(context);

但是，对 CGContextStrokePath 的调用清除了当前路径，因此 CGContextFillPath 将什么也不做。要在同一路径上描边和填充，您应该使用CGContextDrawPath：

    ...
    CGContextSetStrokeColorWithColor(context, [UIColor blueColor].CGColor);
    CGContextAddPath(context, path);
//  CGContextStrokePath(context);
    CGContextSetFillColorWithColor(context, [UIColor redColor].CGColor);
//  CGContextFillPath(path);
    CGContextDrawPath(context, kCGPathFillStroke);

（并且还应用@Luiz关于获取上下文的更改。）

于 2011-11-29T15:13:24.657 回答
1

您需要在添加路径之前获取上下文：

context = UIGraphicsGetCurrentContext();    
CGContextAddPath(context, path);

此外，要填充路径，您需要传递上下文引用，而不是路径本身：

CGContextFillPath(context);
于 2011-11-29T15:17:57.813 回答