Android seekbar solution

I found that the problem with Ravi's solution is that touching and moving outside of the current thumb position would still result in a jump.

The class below resolves that issue and replaces the jump-on-touch with a small increment, the same as one would get with arrow keys.


import android.content.Context;
import android.graphics.Rect;
import android.util.AttributeSet;
import android.view.KeyEvent;
import android.view.MotionEvent;
import android.widget.SeekBar;

/**
 * A NoSkipSeekBar is an extension of {@link SeekBar} that prevents jumps in position
 * by touching outside the current thumb position. Such touches are replaced by
 * an increment or decrement the same as would be achieved using a DPAD's Left or
 * Right arrow keys.
 */
public class NoSkipSeekBar extends SeekBar {

    public NoSkipSeekBar(Context context) {
        super(context);
    }

    public NoSkipSeekBar(Context context, AttributeSet attrs) {
        super(context, attrs);
    }

    public NoSkipSeekBar(Context context, AttributeSet attrs, int defStyle) {
        super(context, attrs, defStyle);
    }

    private boolean isDragging;

    private boolean isWithinThumb(MotionEvent event) {
        return getThumb().getBounds().contains((int)event.getX(), (int)event.getY());
    }

    private void increment(int direction) {
        if (direction != 0) {
            final KeyEvent key = new KeyEvent(KeyEvent.ACTION_DOWN, 
                    direction < 0 ? KeyEvent.KEYCODE_DPAD_LEFT : KeyEvent.KEYCODE_DPAD_RIGHT);
            onKeyDown(key.getKeyCode(), key);
        }
    }

    @Override
    public boolean onTouchEvent(MotionEvent event) {
        if (!isEnabled() || getThumb() == null) return super.onTouchEvent(event);

        switch (event.getAction()) {
        case MotionEvent.ACTION_DOWN:
            if (isWithinThumb(event)) {
                isDragging = true;
                return super.onTouchEvent(event);
            } else {
                return true;
            }

        case MotionEvent.ACTION_UP:
            isDragging = false;
            if (isWithinThumb(event)) {
                return super.onTouchEvent(event);
            } else {
                final Rect r = getThumb().getBounds();
                increment((int)event.getX() - (r.left + r.right) / 2);
                return true;
            }

        case MotionEvent.ACTION_MOVE:
            if (!isDragging) return true;
            break;

        case MotionEvent.ACTION_CANCEL:
            isDragging = false;
            break;
        }

        return super.onTouchEvent(event);
    }
}

Override the OnTouchListener for the seekbar and only process the movement on the thumb when the MotionEvent is a move event.

event.getAction() == MotionEvent.ACTION_MOVE

Update : 1

Something like this will work but the catch is that even if the user moves the thumb 2 units the seekbar moves. And you should really not stop this behavior as it would mess the the seekbar.

seekBar.setOnTouchListener(new OnTouchListener() {

            @Override
            public boolean onTouch(View v, MotionEvent event) {
                if(event.getAction() == MotionEvent.ACTION_MOVE){
                    Log.d(TAG, "Moved , process data, Moved to :" + seekBar.getProgress());
                    seekBar.setProgress(seekBar.getProgress());
                    return false;
                }
                Log.d(TAG, "Touched , Progress :" + seekBar.getProgress());
                return true;
            }
        });