お世話になります。
表題の通り、HorizontalScrollviewを継承したCustomViewを作成し、
xmlにCustomViewを配置したのですが、何故か横スクロールされずに困っております。

CustomView

public final class ScrollCustom extends HorizontalScrollView {


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

    @Override
    public int getMaxScrollAmount() {
        return super.getMaxScrollAmount();
    }

    @Override
    protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
        super.onMeasure(widthMeasureSpec, heightMeasureSpec);
    }

    @Override
    protected void onScrollChanged(int l, int t, int oldl, int oldt) {
        super.onScrollChanged(l, t, oldl, oldt);
    }

    @Override
    protected void onDraw(Canvas canvas) {
        super.onDraw(canvas);
    }

    @Override
    public boolean onInterceptTouchEvent(MotionEvent event)  {
        Log.v("Test", "RecycleTest" + " onInterceptTouchEvent");

        int x = (int) event.getX();
        int y = (int) event.getY();

        switch (event.getAction()) {
            case MotionEvent.ACTION_DOWN:
                TaskRecyclerAdapter.downWidth = x;
                TaskRecyclerAdapter.downHeight = y;

                screenX = x;
                screenY = y;
                Log.v("Test", "RecycleTest" + ", ACTION_DOWN " + x + " : " + y);
                break;

            case MotionEvent.ACTION_MOVE:
                TaskRecyclerAdapter.moveWidth = x;
                TaskRecyclerAdapter.moveHeight = y;
                Log.v("Test", "RecycleTest" + ", ACTION_MOVE " + x + " : " + y);
                break;

            case MotionEvent.ACTION_UP:
                TaskRecyclerAdapter.upWidth = x;
                TaskRecyclerAdapter.upHeight = y;
                Log.v("Test", "RecycleTest" + ", ACTION_UP " + x + " : " + y);
                break;
        }
        return false;
    }

    @Override
    public boolean onTouchEvent(MotionEvent event)  {
        Log.v("Test", "RecycleTest" + " onTouchEvent");
        return false;
    }
}

xml

 <number_8.co.jp.constructiontaskapp.view.ScrollCustom
    android:id="@+id/kanban_scroll"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    app:layout_behavior="@string/appbar_scrolling_view_behavior"
    >
    <android.support.v7.widget.RecyclerView
        android:id="@+id/kanban_recyclerview"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:layout_marginEnd="10dp"
        android:layout_marginStart="10dp"
        android:paddingTop="10dp"
        app:layout_behavior="@string/appbar_scrolling_view_behavior"
        />
</number_8.co.jp.constructiontaskapp.view.ScrollCustom>

初心者ですのでおかしな点はあると思いますが
ご教示の程よろしくお願いします。