安卓系统。过滤列表视图时检查错误的项目[英] Android: Wrong item checked when filtering listview

问题描述

I'm suffering from the same issue as this question: Wrong item checked when filtering ListView in android

As suggested in the above question, I have an Hashset holding all the selectedIds, but I can't figure out how to use it when the cursor is repopulating the checked items.

My issue is only cosmetic - for example:

• "Facebook" is located at the 5th position in the unfiltered list.
• User searched for "face", only "Facebook" appears in the 1st position in the filtered list.
• User checks "Facebook" as selected and goes back to the unfiltered list.
• The checked item is the 1st item in the list and not "Facebook" (positioned 5th).

Note: Except this issue, everything else works great. For example, "delete" will delete the right items because I use the selectedIds to do it (even if the checked items are wrong).

Single click on a list item:

OnItemClickListener mOnItemClickListener = new OnItemClickListener() {
            @Override
            public void onItemClick(AdapterView<?> parent, View v, int position, long id) {

                //gets the Bookmark ID of selected position
                    Cursor cursor = (Cursor)parent.getItemAtPosition(position);
                    String bookmarkID = cursor.getString(0);

                    boolean currentlyChecked = checkedStates.get(position);
                    checkedStates.set(position, !currentlyChecked);

                    if (!selectedIds.contains(bookmarkID)) {

                        selectedIds.add(bookmarkID);
                        selectedLines.add(position);

                    } else {

                        selectedIds.remove(bookmarkID);
                        selectedLines.remove(position);


                        }

            }
        };

Inside the Cursor: - this is where the problem lies.

This repopulates the checked items - the problem is it does it by position (pos) and what was the right position of the item in the filtered list, is not its position in the unfiltered list - resulting in a wrongly marked item.

CheckedTextView markedItem = (CheckedTextView) row.findViewById(R.id.btitle);
markedItem.setChecked(checkedStates.get(pos));

Would appreciate any help!

推荐答案

Solved the issue. As suggested in the question I added to mine, when you populate the checkboxes, the other List/Hashset should determine whether to mark item as checked or not.

Using my code:

//first you will need to get the current item ID
String bookmarkID = cursor.getString(0);

//Then, check if the current ID is in the selectedIds hash/list
//If true - mark current item view as checked, else - uncheck.
        CheckedTextView markedItem = (CheckedTextView) row.findViewById(R.id.btitle);
        if (selectedIds.contains(new String(bookmarkID))) {
            markedItem.setChecked(true);

        } else {
            markedItem.setChecked(false);
}

Really hope this will help anyone! :)

其他推荐答案

Could it be simply that you ListView does not know the data set changed? Call notifyDatSetChanged() on your adapter to let it know.

my_adapter.notifyDataSetChanged();

This will force a redraw of the list, with the updated data.

其他推荐答案

This is my solution:

• To selecte an item in list view after filtering, at the beginning, I got wrong item because I used this:

  ItemData item = listItems.get(position);
  

The correct way should be like this:

    ItemData item = (ItemData) parent.getItemAtPosition(position);

• To delete an item after filtered, I have tried this:

  for(int i=0;i<listItems.size();i++){
      if(listItems.get(i).getItemID() == item.getItemID()){
          listItems.remove(i);
          myAdapter.notifyDataSetChanged();
     }
  }
  

But that didn't worked because my custom adapter. In my custom adapter, to use filter, I have two listItems:

    ArrayList<ItemData> listItemsToShow = new ArrayList< ItemData >();
    ArrayList< ItemData > listItemsBackup = new ArrayList< ItemData >();

So to delete an item, I added new method in my custom adapter:

    public void deleteItem(String itemID) {
    for (int i = 0; i < listItemsToShow.size(); i++) {
        if (listItemsToShow.get(i).getId().equals(itemID)) {
            listItemsToShow.remove(i);
            break;
        }
    }

    for (int i = 0; i < listItemsBackup.size(); i++) {
        if (listItemsBackup.get(i).getId().equals(itemID)) {
            listItemsBackup.remove(i);
            break;
        }
    }

Finally to delete an item in list view:

    subjectBaseAdapter.deleteItem(subject.getId());
    subjectBaseAdapter.notifyDataSetChanged();

Hope this help