Drag and Drop is useful in canvas or drawing application.Here is full description,just follow it.
- Modify the code in activity_main.xml file.
activity_main.xml
<?xml version="1.0" encoding="utf-8"?>
<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:id="@+id/LinearLayout01"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:gravity="center" >
<Button
android:id="@+id/btn"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Drag Me" >
</Button>
</FrameLayout>
- Add below code in MainActivity.java file.
MainActivity.java
public class Home extends Activity implements OnTouchListener {
private final static int START_DRAGGING = 0;
private final static int STOP_DRAGGING = 1;
private Button btn;
private FrameLayout layout;
private int status;
private LayoutParams params;
private ImageView image;
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
layout = (FrameLayout) findViewById(R.id.LinearLayout01);
// layout.setOnTouchListener(this);
btn = (Button) findViewById(R.id.btn);
btn.setDrawingCacheEnabled(true);
btn.setOnTouchListener(this);
params = new LayoutParams(LayoutParams.WRAP_CONTENT,
LayoutParams.WRAP_CONTENT);
}
@Override
public boolean onTouch(View view, MotionEvent me)
{
if (me.getAction() == MotionEvent.ACTION_DOWN) {
status = START_DRAGGING;
image = new ImageView(this);
image.setImageBitmap(btn.getDrawingCache());
layout.addView(image, params);
}
if (me.getAction() == MotionEvent.ACTION_UP) {
status = STOP_DRAGGING;
Log.i("Drag", "Stopped Dragging");
} else if (me.getAction() == MotionEvent.ACTION_MOVE) {
if (status == START_DRAGGING) {
System.out.println("Dragging");
image.setPadding((int) me.getRawX(), (int) me.getRawY(), 0, 0);
image.invalidate();
}
}
return false;
}
}
- Done ! Now Run the Project.Try to drag button.
