ios CGContextRef填充颜色
我想画一条弧并填充它。第一张图片就是它的样子。我想得到第二幅画的效果ios CGContextRef填充颜色,ios,objective-c,iphone,Ios,Objective C,Iphone,我想画一条弧并填充它。第一张图片就是它的样子。我想得到第二幅画的效果 - (id)initWithFrame:(CGRect)frame { if (self = [super initWithFrame:frame]) { // 必须清空背景色,不然绘制出来的区域之外有黑色背景 [self setBackgroundColor:[UIColor clearColor]]; [self setUserInteractionEnabled:NO]; }
- (id)initWithFrame:(CGRect)frame {
if (self = [super initWithFrame:frame]) {
// 必须清空背景色,不然绘制出来的区域之外有黑色背景
[self setBackgroundColor:[UIColor clearColor]];
[self setUserInteractionEnabled:NO];
}
return self;
}
- (void)drawRect:(CGRect)rect {
float x = rect.origin.x;
float y = rect.origin.y;
float w = rect.size.width;
float h = rect.size.height;
CGContextRef context = UIGraphicsGetCurrentContext();
UIColor *fullColor = [UIColor whiteColor];
CGContextSetFillColorWithColor(context, fullColor.CGColor);
CGContextSetRGBStrokeColor(context,1,1,1,1);
CGContextMoveToPoint(context,0,h - 22);//圆弧的起始点
CGContextAddQuadCurveToPoint(context, w / 2, h, w, h - 22);
CGContextMoveToPoint(context,0,h - 22);//圆弧的起始点
CGContextAddLineToPoint(context, 0, h);
CGContextAddLineToPoint(context, w, h);
CGContextAddLineToPoint(context, w, h - 22);
CGContextStrokePath(context);
CGContextDrawPath(context, kCGPathFillStroke);
}
我找到了一个解决方案。CGContextStrokePath()
清除当前路径。这也适用于CGContextDrawPath()
,cgContextOfillPath()
,以及CGContextFillPath()
因此,当调用CGContextDrawPath(context,kCGPathFillStroke)时代码>时,上下文中的当前路径刚刚被清除,是空路径,未绘制任何内容
删除行CGContextStrokePath(上下文)上面的代码>应该可以解决您的问题
- (void)drawRect:(CGRect)rect {
float x = rect.origin.x;
float y = rect.origin.y;
float w = rect.size.width;
float h = rect.size.height;
CGContextRef context = UIGraphicsGetCurrentContext();
CGContextSetFillColorWithColor(context, [UIColor whiteColor].CGColor);
CGContextFillRect(context, CGRectMake(0, h - 22, kScreenWidth , 22));
CGContextSetFillColorWithColor(context, [UIColor clearColor].CGColor);
// This method
CGContextSetBlendMode(context, kCGBlendModeClear);
CGContextMoveToPoint(context,0,h - 22);
CGContextAddQuadCurveToPoint(context, w / 2, h + 14, w, h - 22);
CGContextDrawPath(context, kCGPathFill);
// This method
CGContextSetBlendMode(context, kCGBlendModeNormal);
}