// destroy drag view
private void stopDrag(int itemIndex) {
if (mDragView != null) {
if (mDragNDropListener != null) mDragNDropListener.onStopDrag(getChildAt(itemIndex));
mDragView.setVisibility(GONE);
WindowManager wm = (WindowManager) getContext().getSystemService(Context.WINDOW_SERVICE);
wm.removeView(mDragView);
mDragView.setImageDrawable(null);
mDragView = null;
}
}
// move the drag view
private void drag(int x, int y) {
if (mDragView != null) {
WindowManager.LayoutParams layoutParams =
(WindowManager.LayoutParams) mDragView.getLayoutParams();
layoutParams.x = x;
layoutParams.y = y - mDragPointOffset;
WindowManager mWindowManager =
(WindowManager) getContext().getSystemService(Context.WINDOW_SERVICE);
mWindowManager.updateViewLayout(mDragView, layoutParams);
if (mDragNDropListener != null)
mDragNDropListener.onDrag(x, y, null); // change null to "this" when ready to use
}
}
@Override
public boolean onTouchEvent(MotionEvent ev) {
if (ev.getActionIndex() != 0) {
return super.onTouchEvent(ev);
}
final int action = ev.getAction();
final int x = (int) ev.getX(0);
final int y = (int) ev.getY(0);
if (action == MotionEvent.ACTION_DOWN
&& x > getWidth() - 80) { // drag on the right part of the item only
mDragMode = true;
}
if (!mDragMode) {
return super.onTouchEvent(ev);
}
switch (action) {
case MotionEvent.ACTION_DOWN:
mStartPosition = pointToPosition(x, y);
if (mStartPosition != INVALID_POSITION) {
int mItemPosition = mStartPosition - getFirstVisiblePosition();
mDragPointOffset = y - getChildAt(mItemPosition).getTop();
mDragPointOffset -= ((int) ev.getRawY()) - y;
startDrag(mItemPosition, y);
drag(0, y); // replace 0 with x if desired
}
break;
case MotionEvent.ACTION_MOVE:
drag(0, y); // replace 0 with x if desired
break;
case MotionEvent.ACTION_CANCEL:
case MotionEvent.ACTION_UP:
default:
mDragMode = false;
int endPosition = pointToPosition(x, y);
stopDrag(mStartPosition - getFirstVisiblePosition());
if (mDragNDropListener != null
&& mStartPosition != INVALID_POSITION
&& endPosition != INVALID_POSITION)
mDragNDropListener.onDrop(mStartPosition, endPosition);
break;
}
return ev.getPointerCount() <= 1 || super.onTouchEvent(ev);
}
// enable the drag view for dragging
private void startDrag(int itemIndex, int y) {
stopDrag(itemIndex);
View item = getChildAt(itemIndex);
if (item == null) return;
if (mDragNDropListener != null) mDragNDropListener.onStartDrag(item);
WindowManager.LayoutParams mWindowParams = new WindowManager.LayoutParams();
mWindowParams.gravity = Gravity.TOP;
mWindowParams.x = 0;
mWindowParams.y = y - mDragPointOffset;
mWindowParams.height = WindowManager.LayoutParams.WRAP_CONTENT;
mWindowParams.width = WindowManager.LayoutParams.WRAP_CONTENT;
mWindowParams.flags =
WindowManager.LayoutParams.FLAG_NOT_FOCUSABLE
| WindowManager.LayoutParams.FLAG_NOT_TOUCHABLE
| WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON
| WindowManager.LayoutParams.FLAG_LAYOUT_IN_SCREEN
| WindowManager.LayoutParams.FLAG_LAYOUT_NO_LIMITS;
mWindowParams.format = PixelFormat.TRANSLUCENT;
mWindowParams.windowAnimations = 0;
Context context = getContext();
// Create a copy of the drawing cache so that it does not get recycled
// by the framework when the list tries to clean up memory
ImageView v = new ImageView(context);
item.setDrawingCacheEnabled(true);
Bitmap bitmap = Bitmap.createBitmap(item.getDrawingCache());
item.setDrawingCacheEnabled(false);
v.setBackgroundResource(android.R.color.holo_blue_dark);
v.setImageBitmap(bitmap);
WindowManager mWindowManager = (WindowManager) context.getSystemService(Context.WINDOW_SERVICE);
mWindowManager.addView(v, mWindowParams);
mDragView = v;
}
