Android: long click on the child views of a ExpandableListView?

Question

ExpandableListView has a setOnChildClickListener method, but lacks of setOnChildLongClickListener method.

When I added setOnLongClickListener() on child view in getChildView(), whole sublist became completely unclickable (despite of parentView.setOnChildClickListener() present and working before).

How can I enable long clicks on child views?

Answer 1

I managed to get long clicks working on an ExpandableListView child item, using the following:

getExpandableListView().setOnItemLongClickListener(new OnItemLongClickListener() {
    @Override
    public boolean onItemLongClick(AdapterView<?> parent, View view, int position, long id) {
        if (ExpandableListView.getPackedPositionType(id) == ExpandableListView.PACKED_POSITION_TYPE_CHILD) {
            int groupPosition = ExpandableListView.getPackedPositionGroup(id);
            int childPosition = ExpandableListView.getPackedPositionChild(id);

            // You now have everything that you would as if this was an OnChildClickListener() 
            // Add your logic here.

            // Return true as we are handling the event.
            return true;
        }

        return false;
    }
});

It took ages to figure out that the id argument in onItemLongClick was the packedPosition argument required by getPackedPosition* methods, certainly not clear from the documentation.

Note: For this solution to work you need to override the getGroupId and getChildId() methods in your adapter

   @Override
   public long getGroupId(int groupPosition) {
      return groupPosition;
   }

   @Override
   public long getChildId(int groupPosition, int childPosition) {
      return childPosition;
   }

Answer 2

I found an answer on Steve Oliver's blog here: http://steveoliverc.wordpress.com/2009/10/16/context-menus-for-expandable-lists/

You should use onCreateContextMenu() instead of looking for setOnChildLongClickListener(). Here is Steve's info:

An expandable list supports context menus in pretty much the same way that a standard list does: add a listener for the context menu (when the user has long-pressed on a list item). Unlike a standard list view, however, you probably want to know whether the user has selected a group (expandable item) or a child (sub-item) list item.

Furthermore, you might not want to do anything if the user tries to bring up a context menu on a group item. There might be cases where you would want to do something to all of the children under a group, but in my Librarium application, I wanted to ignore group items and present the context menu only for children.

First, you need to know when the context menu is going to be created so that you can identify whether the user pressed on a group or a child. If they pressed on a group, then cancel the context menu. This also gives us a chance to get the text of the child item, so that we can put it into the header of the context menu.

public void onCreateContextMenu(ContextMenu menu, View v,
                                ContextMenuInfo menuInfo)             
{
  super.onCreateContextMenu(menu, v, menuInfo);

  ExpandableListView.ExpandableListContextMenuInfo info =
    (ExpandableListView.ExpandableListContextMenuInfo) menuInfo;

  int type =
    ExpandableListView.getPackedPositionType(info.packedPosition);

  int group =
    ExpandableListView.getPackedPositionGroup(info.packedPosition);

  int child =
    ExpandableListView.getPackedPositionChild(info.packedPosition);

  // Only create a context menu for child items
  if (type == ExpandableListView.PACKED_POSITION_TYPE_CHILD) 
  {
    // Array created earlier when we built the expandable list
    String page =mListStringArray[group][child];

    menu.setHeaderTitle(page);
    menu.add(0, MENU_READ, 0, “Read page”);
    menu.add(0, MENU_EDIT, 0, “Edit page”);
    menu.add(0, MENU_FAVORITE, 0, “Add page to favorites”);
    menu.add(0, MENU_EXPORT, 0, “Export page to file”);
    menu.add(0, MENU_DELETE, 1, “Delete page”);
  }
}

Secondly, create the Context Menu:

public boolean onContextItemSelected(MenuItem menuItem) 
{
  ExpandableListContextMenuInfo info = 
    (ExpandableListContextMenuInfo) menuItem.getMenuInfo();

  int groupPos = 0, childPos = 0;

  int type = ExpandableListView.getPackedPositionType(info.packedPosition);
  if (type == ExpandableListView.PACKED_POSITION_TYPE_CHILD) 
  {
    groupPos = ExpandableListView.getPackedPositionGroup(info.packedPosition);
    childPos = ExpandableListView.getPackedPositionChild(info.packedPosition);
  }

  // Pull values from the array we built when we created the list
  String author = mListStringArray[groupPos][0];
  String page = mListStringArray[groupPos][childPos * 3 + 1];
  rowId = Integer.parseInt(mListStringArray[groupPos][childPos * 3 + 3]);

  switch (menuItem.getItemId()) 
  {
    case MENU_READ:
      readNote(rowId);
      return true;

    case MENU_EDIT:
      editNote(rowId);
      return true;

    // etc..

    default:
      return super.onContextItemSelected(menuItem);
  }
}

That’s it. Now users can long-press on an item in an expandable list, and get the context menu if it’s a child item.

Answer 3

I know this answer may be no need, but I have similar situation and non of these answer solve my problem. So I post mine in case someone may need it. Hope all you guys don't mind.

@Override
                public boolean onItemLongClick(AdapterView<?> parent, View childView, int flatPos, long id) {
                     if (ExpandableListView.getPackedPositionType(id) == ExpandableListView.PACKED_POSITION_TYPE_CHILD) {
                            final ExpandableListAdapter adapter = ((ExpandableListView) parent).getExpandableListAdapter();
                            long packedPos = ((ExpandableListView) parent).getExpandableListPosition(flatPos);
                            int groupPosition = ExpandableListView.getPackedPositionGroup(packedPos);
                            int childPosition = ExpandableListView.getPackedPositionChild(packedPos);

                        // do whatever you want with groupPos and childPos here - I used these to get my object from list adapter.
                    return false;
                }

Edit This solution for Listview was long time ago. I highly recommend to move to RecyclerView now.

Answer 4

I was searching for this answer, but non here gave correct results.

Marked answer from tomash suggest completely different way. Answer from Nicholas is partially correct, but using 'id' is incorrect.

Correct, working, answer is: convert position parameter to packedPosition and THEN! using this new packedPosition value to obtain group and child ID's. Check code below

    getExpandableListView().setOnItemLongClickListener(new AdapterView.OnItemLongClickListener() {

        @Override
        public boolean onItemLongClick(AdapterView<?> parent, View view, int position, long id) {
            long packedPosition = getExpandableListView().getExpandableListPosition(position);
            if (ExpandableListView.getPackedPositionType(packedPosition) == 
                    ExpandableListView.PACKED_POSITION_TYPE_CHILD) {
                // get item ID's
                int groupPosition = ExpandableListView.getPackedPositionGroup(packedPosition);
                int childPosition = ExpandableListView.getPackedPositionChild(packedPosition);

                // handle data 
                ...

                // return true as we are handling the event.
                return true;
            }
            return false;
        }
    });

EDIT: I now see that autobot has almost correct solution, except testing getPackedPositionType on id and not on packetPosition