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自定义控件时能保存onDraw中的canvas吗？

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自定义控件时能保存onDraw中的canvas吗？

我指的是将onDraw的参数canvas用类成员变量保存着，在onTouchEvent中直接使用这个canvas进行drawLine等等操作，有没有这种做法？


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by (71.8m points)

这样做应该只是不会崩溃而已吧, 实际输出会得不到你想要的结果. 因为你在人为的破坏View的draw机制.

如果需要重绘, 在View#onTouchEvent(...)时, 设置好draw需要的参数(非canvas), 然后再调用 View#invalidate(), 通知View重绘.


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