Clearing CGPath path after drawing is done

问题

I've written a program for drawing in iOS in touchesMoved() method.

CGContextAddPath(UIGraphicsGetCurrentContext(), path);
CGPathMoveToPoint(path, NULL, lastPoint.x, lastPoint.y);
CGPathAddLineToPoint(path, NULL, lastPoint.x, lastPoint.y);
CGContextDrawPath(UIGraphicsGetCurrentContext(), kCGPathStroke);

How can i clear the path drawn and restore the original view?

回答1:

Perhaps you can put an invisible view above your view of drawing and add the path traced by the user only when u are sure that the user will not undo. If the user wants the undo action, don't add the path to the context. Thats my logic. I am not sure how it can be implemted. Hope this helps.

来源：https://stackoverflow.com/questions/9094772/clearing-cgpath-path-after-drawing-is-done