Yassine El Malyh Yassine El Malyh - 10 months ago 61
Android Question

android divide image into sub images ,recognizing

I want to divide the image into sub images and when I click on a part of the image will give me the name of the region, for example, this is my question how to recognize a region from the image, or how to divide the image into sub-images and use it in imageViews

And thank you in advance

Answer Source

In my opinion @fractalwrench's idea is quite good for your case. Basic steps are listed below.

  • Subclass Android ImageView. For example, MultiRegionImageView.
  • Override its onTouchEvent method. (This method gets called whenever user touches the view)
  • User touches the image and thereby onTouchEvent is called and provides the exact touch point (x, y).

  • Declare another method or interface which determines at which region a given point is. For example, getRegionByPoint(int x, int y)

  • If you would like to highlight that region boundaries, you could use paths. First off, you should define paths and save them into a raw file (XML, for example), then using region ID, fetch its path and finally draw that path over the main image.

  • For drawing a path over the main image, you should also override onDraw method of ImageView class and use canvas.drawPath();

public class MultiRegionImageView extends ImageView {
    RegionProvider mRegionProvider;
    int mId = -1;
    private Paint mPaint;

    public MultiRegionImageView(Context context) {

    public boolean onTouchEvent(MotionEvent event) {
        mId = mRegionProvider.getRegionIdByPoint(event.getX(), event.getY());
        return super.onTouchEvent(event);

    protected void onDraw(Canvas canvas) {
        if(mId != -1) {
            canvas.drawPath(mRegionProvider.getRegionBoundaryPath(mId), mPaint);

    public interface RegionProvider{
        int getRegionIdByPoint(float x, float y);
        Path getRegionBoundaryPath(int id);