Android: How to get the area size of a drawn path?

问题

My problem is to measure the surface area of a path.
I generate a random Path and draw it on a canvas. After touching on this closen path, i want to get the area size of this drawn path.

How can i get the real area size of this path?

The pathes (shapes) looks like this here:
link to the image

回答1:

I found a solution. I generate a Region from the path and use a RegionIterator to get Rects inside the Region. With this Rects i can calculate the whole area of the path.

private void calculateArea(Region region) {

        RegionIterator regionIterator = new RegionIterator(region);

        int size = 0; // amount of Rects
        float area = 0; // units of area

        Rect tmpRect= new Rect(); 

        while (regionIterator.next(tmpRect)) {
            size++;
            area += tmpRect.width() * tmpRect.height();
        }

        log.d("Rect amount=" + size);
        log.d("Area Size / units of area=" + area);
}

来源：https://stackoverflow.com/questions/17236451/android-how-to-get-the-area-size-of-a-drawn-path