Scrolling a HorizontalScrollView by clicking buttons on its sides

Question

I am using a HorizontalScrollView within a Fragment. When I scroll this view instead of scrolling the items within HorizontalScrollView

Answer 1

If you add the following line of code to your existing handler, your view will scroll right with every button click:

rightBtn.setOnClickListener(new View.OnClickListener() {

    @Override
    public void onClick(View v) {
        hsv.scrollTo((int)hsv.getScrollX() + 10, (int)hsv.getScrollY());
    }
});

If you'd like it to scroll more smoothly you can use an onTouchListener instead:

rightBtn.setOnTouchListener(new View.OnTouchListener() {

    private Handler mHandler;
    private long mInitialDelay = 300;
    private long mRepeatDelay = 100;

    @Override
    public boolean onTouch(View v, MotionEvent event) {
        switch (event.getAction()) {
            case MotionEvent.ACTION_DOWN:
                if (mHandler != null)
                    return true;
                mHandler = new Handler();
                mHandler.postDelayed(mAction, mInitialDelay);
                break;
            case MotionEvent.ACTION_UP:
                if (mHandler == null)
                    return true;
                mHandler.removeCallbacks(mAction);
                mHandler = null;
                break;
        }
        return false;
    }

    Runnable mAction = new Runnable() {
        @Override
        public void run() {
            hsv.scrollTo((int) hsv.getScrollX() + 10, (int) hsv.getScrollY());
            mHandler.postDelayed(mAction, mRepeatDelay);
        }
    };
});

Vary the delays to your liking to get the smoothness and responsiveness you want.