Example of DragEvent

Create new project named "DragEvent"

main.xml

<?xml version="1.0" encoding="utf-8"?>
<GridLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:columnCount="2"
    android:columnWidth="300dp"
    android:orientation="vertical"
    android:rowCount="2"
    android:stretchMode="columnWidth" >

    <LinearLayout
        android:id="@+id/topleft"
        android:layout_width="160dp"
        android:layout_height="200dp"
        android:layout_column="0"
        android:layout_row="0"
        android:background="@drawable/shape" >

        <ImageView
            android:id="@+id/myimage1"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_column="0"
            android:layout_row="0"
            android:src="@drawable/ic_launcher" />
    </LinearLayout>

    <LinearLayout
        android:id="@+id/topright"
        android:layout_width="160dp"
        android:layout_height="200dp"
        android:layout_column="1"
        android:layout_row="0"
        android:background="@drawable/shape" >

        <ImageView
            android:id="@+id/myimage2"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_column="0"
            android:layout_row="0"
            android:src="@drawable/ic_launcher" />
    </LinearLayout>

    <LinearLayout
        android:id="@+id/bottomleft"
        android:layout_width="160dp"
        android:layout_height="200dp"
        android:layout_column="0"
        android:layout_row="1"
        android:background="@drawable/shape" >

        <ImageView
            android:id="@+id/myimage3"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:src="@drawable/ic_launcher" />
    </LinearLayout>

    <LinearLayout
        android:id="@+id/bottomright"
        android:layout_width="160dp"
        android:layout_height="200dp"
        android:layout_column="1"
        android:layout_row="1"
        android:background="@drawable/shape" >

        <ImageView
            android:id="@+id/myimage4"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_column="0"
            android:layout_row="0"
            android:src="@drawable/ic_launcher" />
    </LinearLayout> 

</GridLayout> 

MainActivity.java

public class MainActivity extends Activity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        findViewById(R.id.myimage1).setOnTouchListener(new MyTouchListener());
        findViewById(R.id.myimage2).setOnTouchListener(new MyTouchListener());
        findViewById(R.id.myimage3).setOnTouchListener(new MyTouchListener());
        findViewById(R.id.myimage4).setOnTouchListener(new MyTouchListener());
        findViewById(R.id.topleft).setOnDragListener(new MyDragListener());
        findViewById(R.id.topright).setOnDragListener(new MyDragListener());
        findViewById(R.id.bottomleft).setOnDragListener(new MyDragListener());
        findViewById(R.id.bottomright).setOnDragListener(new MyDragListener());

      }

      private final class MyTouchListener implements OnTouchListener {
        public boolean onTouch(View view, MotionEvent motionEvent) {
          if (motionEvent.getAction() == MotionEvent.ACTION_DOWN) {
            ClipData data = ClipData.newPlainText("", "");
            DragShadowBuilder shadowBuilder = new View.DragShadowBuilder(view);
            view.startDrag(data, shadowBuilder, view, 0);
            view.setVisibility(View.INVISIBLE);
            return true;
          } else {
            return false;
          }
        }
      }

      class MyDragListener implements OnDragListener {
        Drawable enterShape = getResources().getDrawable(R.drawable.shape_droptarget);
        Drawable normalShape = getResources().getDrawable(R.drawable.shape);

        @Override
        public boolean onDrag(View v, DragEvent event) {
          int action = event.getAction();
          switch (event.getAction()) {
          case DragEvent.ACTION_DRAG_STARTED:
            // do nothing
            break;
          case DragEvent.ACTION_DRAG_ENTERED:
            v.setBackgroundDrawable(enterShape);
            break;
          case DragEvent.ACTION_DRAG_EXITED:
            v.setBackgroundDrawable(normalShape);
            break;
          case DragEvent.ACTION_DROP:
            // Dropped, reassign View to ViewGroup
            View view = (View) event.getLocalState();
            ViewGroup owner = (ViewGroup) view.getParent();
            owner.removeView(view);
            LinearLayout container = (LinearLayout) v;
            container.addView(view);
            view.setVisibility(View.VISIBLE);
            break;
          case DragEvent.ACTION_DRAG_ENDED:
            v.setBackgroundDrawable(normalShape);
           
            default:
            break;
          }
          return true;
        }
      }
    }