Trigger click and drag actions from item in RecyclerView

I have a vertically scrolling RecyclerView and I want to allow items on it to be clicked and reordered.

Each item in the RecyclerView has a "StatusIndicator" on the left hand side (inheriting from an AppCompatImageButton). I've added a GestureDetector to the StatusIndicator and this seems to work except that the vertical drag doesn't get sent to the StatusIndicator.

The behaviour I see is that if I attempt vertical scrolling on the StatusIndicator (intending to trigger a drag) neither the drag is triggered nor the RecyclerView is scrolled. If I continue the scrolling gesture but scroll horizontally suddenly I can drag the item.

I'm assuming the ACTION_DOWN event reaches the StatusIndicator's GestureDetector to trigger the drag but that the RecyclerView captures the following (predominantly vertical) ACTION_MOVE assuming it needs to handle them for it's vertical scroll. Once the gesture involves more horizontal than vertical movement RecyclerView::onInterceptTouchEvent no longer captures the event (confirmed in debug) and the ACTION_MOVEs are then sent to the StatusIndicator as intended.

What is the correct approach here?

The relevant bits of StatusIndicator.java:

class StatusIndicator extends AppCompatImageButton {
    class GestureTouch extends GestureDetector.SimpleOnGestureListener {
        @Override
        public boolean onDown(MotionEvent event) {
            return true;
        }

        @Override
        public boolean onSingleTapConfirmed(MotionEvent e) {
            if (mStatusIndicatorListener != null)
                mStatusIndicatorListener.incrementStatus();
            createDrawableState();
            return true;
        }

        @Override
        public boolean onScroll (MotionEvent e1,
                                 MotionEvent e2,
                                 float distanceX,
                                 float distanceY) {
            mStatusIndicatorListener.startDrag();
            return true;
        }
    }

    private StatusIndicatorListener mStatusIndicatorListener;
    private GestureDetector mTouchDetector;

    public StatusIndicator(Context context, AttributeSet attrs) {
        super(context, attrs);
        mTouchDetector = new GestureDetector(context,new GestureTouch());
    }

    @Override
    public boolean onTouchEvent(MotionEvent event) {
        mTouchDetector.onTouchEvent(event);
        return true;
    }

I believe what was happenning was that any ACTION_MOVE event was heading down the stack and being captured by the RecyclerView within its onInterceptTouchEvent method. Within this RecyclerView.LayoutManager.canScrollVertically() is used to determine that the RecyclerView should capture the event.

In the end I inherited from LinearLayoutManager and overrode canScrollVertically() so I could manually block it with a call to a new method. Then, within RecyclerView.onInterceptTouchEvent, I checked whether the incoming ACTION_DOWN event was over the StatusIndicator and, if so, forced RecyclerView.LayoutManater.canScrollVertically() to return false until the next ACTION_DOWN event.

This is a pretty hacky solution but appears robust. If anyone comes along with a "proper" solution I'd be keen to see it!

The new layout manager:

public class ListLayoutManager extends LinearLayoutManager {
    boolean mScrollBlocked;

    public ListLayoutManager(Context context) {
        super(context);
        mScrollBlocked = false;
    }

    @Override
    public boolean canScrollVertically() {
        return (!mScrollBlocked && super.canScrollVertically());
    }

    public void blockScrolling() {
        mScrollBlocked = true;
    }
    public void unblockScrolling() {
        mScrollBlocked = false;
    }
}

The extended RecyclerView with overridden onInterceptTouchEvent:

    ListLayoutManager mListLayoutManager;

    public ListRecyclerView(Context context) {
        super(context);
    }
    public ListRecyclerView(Context context, AttributeSet attrs) {
        super(context, attrs);
    }
    public ListRecyclerView(Context context, AttributeSet attrs, int defStyleAttr) {
        super(context, attrs, defStyleAttr);
    }

    // We override touch handling so the RecyclerView doesn't handle
    // anything which occurs over the StatusIndicator.
    @Override
    public boolean onInterceptTouchEvent(MotionEvent e) {
        if (e.getActionMasked() == MotionEvent.ACTION_DOWN) {
            mListLayoutManager.unblockScrolling();

            View child = findChildViewUnder(e.getX(), e.getY());
            if (child != null) {
                StatusIndicator statusInd = child.findViewById(R.id.rowStatus);
                if ((statusInd != null) &&
                    (e.getX() <= statusInd.getWidth())) {
                    mListLayoutManager.blockScrolling();
                }
            }
        }
        return super.onInterceptTouchEvent(e);
    }

    public void setListLayoutManager(ListLayoutManager lm) {
        mListLayoutManager = lm;
        setLayoutManager(mListLayoutManager);
    }
}