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android - Fill the complete canvas but keep the bound fill area as it is like circle, rectangle

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Hello friends,

I creating paint application, I have problem in that. If I draw the rectangle without fill and or another like bound area and change the background color then rectangle fill area also change means whole canvas color will be filled with the new background color. How to keep the background or fill the canvas area which was not bound, here is the image

this is the initial image

enter image description here

after change the background color getting this result

enter image description here

but how to getting like this way

enter image description here

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final Point p1 = new Point();
                p1.x=(int) x; //x co-ordinate where the user touches on the screen
                p1.y=(int) y; //y co-ordinate where the user touches on the screen  
 new TheTask(yourbitmap, p1, sourceColor,targetColor).execute();// use asyntask for efficiency

 class TheTask extends AsyncTask<Void, Integer, Void> {

    Bitmap bmp;
    Point pt;
    int replacementColor,targetColor;
    ProgressDialog pd;
 public TheTask(Bitmap bm,Point p, int sc, int tc)
 {
this.bmp=bm;
this.pt=p;
this.replacementColor=tc;
this.targetColor=sc;
pd= new ProgressDialog(context);
pd.setMessage("Filling....");
    }
    @Override
    protected void onPreExecute() {
            pd.show();

    }

    @Override
    protected void onProgressUpdate(Integer... values) {

    }

    @Override
    protected Void doInBackground(Void... params) {
        FloodFill f= new FloodFill();
        f.floodFill(bmp,pt,targetColor,replacementColor);
        return null;
    }

    @Override
    protected void onPostExecute(Void result) { 
pd.dismiss();
invalidate();
    }

Finally use a FloodFill algorithm to fill a closed area

    public class FloodFill {
public void floodFill(Bitmap  image, Point node, int targetColor,
        int replacementColor) {
    int width = image.getWidth();
    int height = image.getHeight();
    int target = targetColor;
    int replacement = replacementColor;
    if (target != replacement) {
        Queue<Point> queue = new LinkedList<Point>();
        do {
            int x = node.x;
            int y = node.y;
            while (x > 0 && image.getPixel(x - 1, y) == target) {
                x--;
            }
            boolean spanUp = false;
            boolean spanDown = false;
            while (x < width && image.getPixel(x, y) == target) {
                image.setPixel(x, y, replacement);
                if (!spanUp && y > 0 && image.getPixel(x, y - 1) == target) {
                    queue.add(new Point(x, y - 1));
                    spanUp = true;
                } else if (spanUp && y > 0
                        && image.getPixel(x, y - 1) != target) {
                    spanUp = false;
                }
                if (!spanDown && y < height - 1
                        && image.getPixel(x, y + 1) == target) {
                    queue.add(new Point(x, y + 1));
                    spanDown = true;
                } else if (spanDown && y < height - 1
                        && image.getPixel(x, y + 1) != target) {
                    spanDown = false;
                }
                x++;
            }
        } while ((node = queue.poll()) != null);
    }
}
}

enter image description here


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