ListView - Drag and Drop.java

package com.h6ah4i.android.example.dragdrop;

import android.app.Activity;
import android.graphics.Canvas;
import android.graphics.Point;
import android.os.Bundle;
import android.view.DragEvent;
import android.view.LayoutInflater;
import android.view.MotionEvent;
import android.view.View;
import android.view.View.DragShadowBuilder;
import android.view.View.OnDragListener;
import android.view.View.OnTouchListener;
import android.view.ViewGroup;
import android.view.WindowManager;
import android.widget.AdapterView;
import android.widget.BaseAdapter;
import android.widget.ListView;
import android.widget.TextView;

import java.util.ArrayList;
import java.util.List;

public class MainActivity extends Activity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN, WindowManager.LayoutParams.FLAG_FULLSCREEN);

        setContentView(R.layout.activity_main);

        ListView lv = (ListView) findViewById(android.R.id.list);

        List<String> items = new ArrayList<>();
        for (int i = 0; i < 20; i++) {
            items.add(Integer.toString(i));
        }

        lv.setAdapter(new MyAdapter(items));

        lv.setOnItemLongClickListener(new AdapterView.OnItemLongClickListener() {
            @Override
            public boolean onItemLongClick(AdapterView<?> parent, View view, int position, long id) {
                //
                // start dragging
                //
                MyAdapter.ViewHolder vh = (MyAdapter.ViewHolder) view.getTag();

                final int touchedX = (int) (vh.lastTouchedX + 0.5f);
                final int touchedY = (int) (vh.lastTouchedY + 0.5f);

                view.startDrag(null, new DragShadowBuilder(view) {
                    @Override
                    public void onProvideShadowMetrics(Point shadowSize, Point shadowTouchPoint) {
                        super.onProvideShadowMetrics(shadowSize, shadowTouchPoint);
                        shadowTouchPoint.x = touchedX;
                        shadowTouchPoint.y = touchedY;
                    }

                    @Override
                    public void onDrawShadow(Canvas canvas) {
                        super.onDrawShadow(canvas);
                    }
                }, view, 0);

                view.setVisibility(View.INVISIBLE);

                return true;
            }
        });

        lv.setOnDragListener(new OnDragListener() {
            @Override
            public boolean onDrag(View v, DragEvent event) {
                if (event.getAction() == DragEvent.ACTION_DROP) {
                    //
                    // finish dragging
                    //
                    View view = (View) event.getLocalState();
                    view.setVisibility(View.VISIBLE);
                }
                return true;
            }
        });
    }

    static class MyAdapter extends BaseAdapter implements OnTouchListener {
        private List<String> mItems;

        private static class ViewHolder {
            public TextView text;
            public float lastTouchedX;
            public float lastTouchedY;

            public ViewHolder(View v) {
                text = (TextView) v;
            }
        }

        MyAdapter(List<String> items) {
            mItems = items;
        }

        @Override
        public long getItemId(int position) {
            return position;
        }

        @Override
        public View getView(int position, View convertView, ViewGroup parent) {
            View view;
            ViewHolder vh;

            if (convertView == null) {
                view = LayoutInflater.from(parent.getContext()).inflate(android.R.layout.simple_list_item_1, parent, false);
                view.setOnTouchListener(this);
                vh = new ViewHolder(view);
                view.setTag(vh);
            } else {
                view = convertView;
                vh = (ViewHolder) view.getTag();
            }

            vh.text.setText(mItems.get(position));

            return view;
        }

        @Override
        public int getItemViewType(int position) {
            return 0;
        }

        @Override
        public int getCount() {
            return mItems.size();
        }

        @Override
        public Object getItem(int position) {
            return mItems.get(position);
        }

        @Override
        public boolean onTouch(View v, MotionEvent event) {
            ViewHolder vh = (ViewHolder) v.getTag();

            vh.lastTouchedX = event.getX();
            vh.lastTouchedY = event.getY();

            return false;
        }
    }
}

unfortunately drop is not working