Horizontal Scroll View inside ViewPager

Question

I have horizontal scrolling pages as in the android market (ViewPager).

My problem is that i want to have a Horizontal Scrolling View in them with some images?Is that possible??

As now,i m getting a little scroll in my view and then the whole page is scrolling.

Thanks for your time!

Answer 1

You need to extend the HorizontalScrollView and intercept touch events. What worked for me was the following sample:

public class MyScrollView extends HorizontalScrollView {

    public MyScrollView(Context p_context, AttributeSet p_attrs)
    {
        super(p_context, p_attrs);
    }

    @Override
    public boolean onInterceptTouchEvent(MotionEvent p_event)
    {
        return true;
    }

    @Override
    public boolean onTouchEvent(MotionEvent p_event)
    {
        if (p_event.getAction() == MotionEvent.ACTION_MOVE && getParent() != null)
        {
            getParent().requestDisallowInterceptTouchEvent(true);
        }

        return super.onTouchEvent(p_event);
    }
}

Then, instead of using the HorizontalScrollView in your layout XML, you need to use this custom view.

What helped me get to this solution is this post

Answer 2

I've reworked a solution and finally found a very simple way to implement it the same way it's been done on GMail: the HorizontalScrollView will scroll until it reaches one of its edges. Then on next scrolling, the whole page will scroll.

All it required was overriding the HorizontalScrollView to check scroll direction vs edges and also make sure content can actually scroll.

@Override
public boolean onTouchEvent(MotionEvent ev) 
{
    if (no_scrolling)
        return false;

    //  Standard behavior
    //
    return super.onTouchEvent(ev);
}

boolean no_scrolling = false;
float old_x, old_y;
@Override
public boolean onInterceptTouchEvent(MotionEvent ev)
{
    int action = ev.getActionMasked();
    Log.d(at_data.TAG, "HSV scroll intercept: " + String.format("0x%08x", action));

    if (action == MotionEvent.ACTION_DOWN)
    {
        old_x = ev.getX();
        old_y = ev.getY();
        no_scrolling = false;

    }
    else if (action == MotionEvent.ACTION_MOVE)
    {
        float dx = ev.getX() - old_x;
        float dy = ev.getY() - old_y;

        if (Math.abs(dx) > Math.abs(dy) && dx != 0)
        {
            View hsvChild = getChildAt(0);
            int childW = hsvChild.getWidth();
            int W = getWidth();

            Log.d(at_data.TAG, "HSV " + childW + " > " + W + " ? dx = " + dx + " dy = " + dy);
            if (childW > W)
            {
                int scrollx = getScrollX();
                if ( (dx < 0 && scrollx + W >= childW) || (dx > 0 && scrollx <= 0))
                {
                    Log.d(at_data.TAG, "HSV Wider: on edge already");
                    no_scrolling = true;
                    return false;
                }
                else
                {
                    Log.d(at_data.TAG, "HSV Wider: can scroll");
                    no_scrolling = false;
                }
            }
            else
            {
                Log.d(at_data.TAG, "HSV cannot scroll in desired direction");
                no_scrolling = true;
            }
        }
    }

    //  Standard behavior
    //
    return super.onInterceptTouchEvent(ev);
}