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copied!<p>use this code, it's allows operation drug and drop in ListView:</p> <pre><code>public class DraggableListView extends ListView { private static final String LOG_TAG = "tasks365"; private static final int END_OF_LIST_POSITION = -2; private DropListener mDropListener; private int draggingItemHoverPosition; private int dragStartPosition; // where was the dragged item originally private int mUpperBound; // scroll the view when dragging point is moving out of this bound private int mLowerBound; // scroll the view when dragging point is moving out of this bound private int touchSlop; private Dragging dragging; private GestureDetector longPressDetector; public DraggableListView(Context context, AttributeSet attrs) { this(context, attrs, android.R.attr.listViewStyle); } public DraggableListView(final Context context, AttributeSet attrs, int defStyle) { super(context, attrs, defStyle); touchSlop = ViewConfiguration.get(context).getScaledTouchSlop(); longPressDetector = new GestureDetector(getContext(), new SimpleOnGestureListener() { @Override public void onLongPress(final MotionEvent e) { int x = (int) e.getX(); final int y = (int) e.getY(); int itemnum = pointToPosition(x, y); if (itemnum == AdapterView.INVALID_POSITION) { return; } if (dragging != null) { dragging.stop(); dragging = null; } final View item = getChildAt(itemnum - getFirstVisiblePosition()); item.setPressed(false); dragging = new Dragging(getContext()); dragging.start(y, ((int) e.getRawY()) - y, item); draggingItemHoverPosition = itemnum; dragStartPosition = draggingItemHoverPosition; int height = getHeight(); mUpperBound = Math.min(y - touchSlop, height / 3); mLowerBound = Math.max(y + touchSlop, height * 2 / 3); } }); setOnItemLongClickListener(new OnItemLongClickListener() { @SuppressWarnings("unused") public boolean onItemLongClick(AdapterView<?> paramAdapterView, View paramView, int paramInt, long paramLong) { // Return true to let AbsListView reset touch mode // Without this handler, the pressed item will keep highlight. return true; } }); } /* pointToPosition() doesn't consider invisible views, but we need to, so implement a slightly different version. */ private int myPointToPosition(int x, int y) { if (y < 0) { return getFirstVisiblePosition(); } Rect frame = new Rect(); final int count = getChildCount(); for (int i = 0; i < count; i++) { final View child = getChildAt(i); child.getHitRect(frame); if (frame.contains(x, y)) { return getFirstVisiblePosition() + i; } } if ((x >= frame.left) && (x < frame.right) && (y >= frame.bottom)) { return END_OF_LIST_POSITION; } return INVALID_POSITION; } @Override public boolean onTouchEvent(MotionEvent ev) { if (longPressDetector.onTouchEvent(ev)) { return true; } if ((dragging == null) || (mDropListener == null)) { // it is not dragging, or there is no drop listener return super.onTouchEvent(ev); } int action = ev.getAction(); switch (ev.getAction()) { case MotionEvent.ACTION_UP: case MotionEvent.ACTION_CANCEL: dragging.stop(); dragging = null; if (mDropListener != null) { if (draggingItemHoverPosition == END_OF_LIST_POSITION) { mDropListener.drop(dragStartPosition, getCount() - 1); } else if (draggingItemHoverPosition != INVALID_POSITION) { mDropListener.drop(dragStartPosition, draggingItemHoverPosition); } } resetViews(); break; case MotionEvent.ACTION_DOWN: case MotionEvent.ACTION_MOVE: int x = (int) ev.getX(); int y = (int) ev.getY(); dragging.drag(x, y); int position = dragging.calculateHoverPosition(); if (position != INVALID_POSITION) { if ((action == MotionEvent.ACTION_DOWN) || (position != draggingItemHoverPosition)) { draggingItemHoverPosition = position; doExpansion(); } scrollList(y); } break; } return true; } private void doExpansion() { int expanItemViewIndex = draggingItemHoverPosition - getFirstVisiblePosition(); if (draggingItemHoverPosition >= dragStartPosition) { expanItemViewIndex++; } // Log.v(LOG_TAG, "Dragging item hovers over position " + draggingItemHoverPosition + ", expand item at index " // + expanItemViewIndex); View draggingItemOriginalView = getChildAt(dragStartPosition - getFirstVisiblePosition()); for (int i = 0;; i++) { View itemView = getChildAt(i); if (itemView == null) { break; } ViewGroup.LayoutParams params = itemView.getLayoutParams(); int height = LayoutParams.WRAP_CONTENT; if (itemView.equals(draggingItemOriginalView)) { height = 1; } else if (i == expanItemViewIndex) { height = itemView.getHeight() + dragging.getDraggingItemHeight(); } params.height = height; itemView.setLayoutParams(params); } } /** * Reset view to original height. */ private void resetViews() { for (int i = 0;; i++) { View v = getChildAt(i); if (v == null) { layoutChildren(); // force children to be recreated where needed v = getChildAt(i); if (v == null) { break; } } ViewGroup.LayoutParams params = v.getLayoutParams(); params.height = LayoutParams.WRAP_CONTENT; v.setLayoutParams(params); } } private void resetScrollBounds(int y) { int height = getHeight(); if (y >= height / 3) { mUpperBound = height / 3; } if (y <= height * 2 / 3) { mLowerBound = height * 2 / 3; } } private void scrollList(int y) { resetScrollBounds(y); int height = getHeight(); int speed = 0; if (y > mLowerBound) { // scroll the list up a bit speed = y > (height + mLowerBound) / 2 ? 16 : 4; } else if (y < mUpperBound) { // scroll the list down a bit speed = y < mUpperBound / 2 ? -16 : -4; } if (speed != 0) { int ref = pointToPosition(0, height / 2); if (ref == AdapterView.INVALID_POSITION) { //we hit a divider or an invisible view, check somewhere else ref = pointToPosition(0, height / 2 + getDividerHeight() + 64); } View v = getChildAt(ref - getFirstVisiblePosition()); if (v != null) { int pos = v.getTop(); setSelectionFromTop(ref, pos - speed); } } } public void setDropListener(DropListener l) { mDropListener = l; } public interface DropListener { void drop(int from, int to); } class Dragging { private Context context; private WindowManager windowManager; private WindowManager.LayoutParams mWindowParams; private ImageView mDragView; private Bitmap mDragBitmap; private int coordOffset; private int mDragPoint; // at what offset inside the item did the user grab it private int draggingItemHeight; private int x; private int y; private int lastY; public Dragging(Context context) { this.context = context; windowManager = (WindowManager) context.getSystemService("window"); } /** * @param y * @param offset - the difference in y axis between screen coordinates and coordinates in this view * @param view - which view is dragged */ public void start(int y, int offset, View view) { this.y = y; lastY = y; this.coordOffset = offset; mDragPoint = y - view.getTop(); draggingItemHeight = view.getHeight(); mDragView = new ImageView(context); mDragView.setBackgroundResource(android.R.drawable.alert_light_frame); // 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 view.setDrawingCacheEnabled(true); mDragBitmap = Bitmap.createBitmap(view.getDrawingCache()); mDragView.setImageBitmap(mDragBitmap); mWindowParams = new WindowManager.LayoutParams(); mWindowParams.gravity = Gravity.TOP; mWindowParams.x = 0; mWindowParams.y = y - mDragPoint + coordOffset; 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; mWindowParams.format = PixelFormat.TRANSLUCENT; mWindowParams.windowAnimations = 0; windowManager.addView(mDragView, mWindowParams); } public void drag(int x, int y) { lastY = this.y; this.x = x; this.y = y; mWindowParams.y = y - mDragPoint + coordOffset; windowManager.updateViewLayout(mDragView, mWindowParams); } public void stop() { if (mDragView != null) { windowManager.removeView(mDragView); mDragView.setImageDrawable(null); mDragView = null; } if (mDragBitmap != null) { mDragBitmap.recycle(); mDragBitmap = null; } } public int getDraggingItemHeight() { return draggingItemHeight; } public int calculateHoverPosition() { int adjustedY = (int) (y - mDragPoint + (Math.signum(y - lastY) + 2) * draggingItemHeight / 2); // Log.v(LOG_TAG, "calculateHoverPosition(): lastY=" + lastY + ", y=" + y + ", adjustedY=" + adjustedY); int pos = myPointToPosition(0, adjustedY); if (pos >= 0) { if (pos >= dragStartPosition) { pos -= 1; } } return pos; } } } </code></pre>

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