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我有一个图像 .PNG（例如只有黑色轮廓的动物图像），我想通过触摸 iPad 屏幕来填充渐变。

我从这里遵循 Apple 的指南

http://developer.apple.com/library/ios/#documentation/2DDrawing/Conceptual/DrawingPrintingiOS/BezierPaths/BezierPaths.html

遵循 Apple 的指南：

- (BOOL)containsPoint:(CGPoint)point onPath:(UIBezierPath *)path inFillArea:  
   (BOOL)inFill {

NSLog(@"contains point Path %@", path);
NSLog(@"Touch point %f %f", point.x, point.y );

CGContextRef context = UIGraphicsGetCurrentContext();
CGPathRef cgPath = path.CGPath;
BOOL    isHit = NO;
// Determine the drawing mode to use. Default to detecting hits on the stroked     
  portion of the path.
CGPathDrawingMode mode = kCGPathStroke;

if (inFill) { // Look for hits in the fill area of the path instead.
    if (path.usesEvenOddFillRule)
        mode = kCGPathEOFill;
    else
        mode = kCGPathFill;
}

 // Save the graphics state so that the path can be removed later.

CGContextSaveGState(context);

 CGContextAddPath(context, cgPath);

// Do the hit detection.
isHit = CGContextPathContainsPoint(context, point, mode);

CGContextRestoreGState(context);

return isHit; }

我只想知道如何在我的应用程序中使用此方法。

告诉我这样做的步骤是什么？

我是新手，请帮助我....

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0 回答 0