#setChecked in CheckedTextView in ListView not working

by William Ferguson » Sat, 14 Aug 2010 12:50:52 GMT


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 I have a ListView that just contains a CheckedTextView.
I have a very simple CursorAdapter that populates CheckedTextViews.
When I click on an item, I can see that I am responding to the correct
row, store the value in my model and the CheckedText gets checked.

However, when I scroll down and then back up again, while I see that
the model contains the correct value (in #bindView), calling
#setChecked on the CheckedTextView has no effect. Ie All items are
unchecked.

Its gotta be something simple, but I can't see it. Any ideas?



public final class SimpleAdapter extends CursorAdapter {

    private static final String TAG = "SimpleAdapter";

    private final LayoutInflater inflater;
    private final RowModel rowModel = new RowModel();

    public SimpleAdapter(Activity context, MyCursor cursor) {
        super(context, cursor, true);
        inflater = (LayoutInflater)
context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
    }

    @Override
    public View newView(Context context, Cursor cursor, ViewGroup
parent) {
        final CheckedTextView checkedText = (CheckedTextView)
inflater.inflate(android.R.layout.simple_list_item_multiple_choice,
parent, false);

        final MyCursor myCursor = (MyCursor) cursor;
        checkedText.setText(myCursor.getDescription());

        final Long rowId = rawContactsCursor.getRowId();
        checkedText.setChecked(rowModel.isSelected(rowId));
        Log.v(TAG, "rowId=" + rowId + " settingChecked=" +
rowModel.isSelected(rowId));

        checkedText.setTag(rowId);

        checkedText.setOnClickListener(new View.OnClickListener() {
            public void onClick(View view) { // Toggle whether the Row
is selected or not.
                final Long id = (Long) view.getTag();
                Log.v(TAG, "toggling rowId=" + rowId);
                final boolean checked = rowModel.toggleSelected(id);
                final CheckedTextView checkedTextView =
(CheckedTextView) view;
                checkedTextView.setChecked(checked);
            }
        });

        return checkedText;
    }

    @Override
    public void bindView(View view, Context context, Cursor cursor) {
        final CheckedTextView checkedText = (CheckedTextView) view;

        final MyCursor myCursor = (MyCursor) cursor;
        checkedText.setText(myCursor.getDescription());

        final Long rowId = rawContactsCursor.getRowId();
        checkedText.setChecked(rowModel.isSelected(rowId));
        Log.v(TAG, "rowId=" + rowId + " settingChecked=" +
rowModel.isSelected(rowId));

        checkedText.setTag(rowId);
    }
}

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#setChecked in CheckedTextView in ListView not working

by Paul Turchenko » Sat, 14 Aug 2010 21:15:28 GMT


 I believe the issue is that you're getting rowId from
rawContactsCursor (bindView method) which stays on the same record.
IMO you should get row id from cursor coming to you in bindView. This
way you'll get rowId for the record you are currently binding.
To be simple, you are binding to the wrong record.

On Aug 14, 7:50am, William Ferguson <william.ferguson...@gmail.com>



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#setChecked in CheckedTextView in ListView not working

by William Ferguson » Sun, 15 Aug 2010 14:29:28 GMT


 m, sorry, in attempting to simplify the example that I presented to
you I didn't manage a full text search and replace.
The text for #bindView should have read (and does in the running code)

@Override
public void bindView(View view, Context context, Cursor cursor) {
final CheckedTextView checkedText = (CheckedTextView) view;
final MyCursor myCursor = (MyCursor) cursor;

final Long rowId = myCursor.getRowId();

checkedText.setChecked(rowModel.isSelected(rowId));
checkedText.setText(myCursor.getDescription());
checkedText.setTag(rowId);

Log.v(TAG, "rowId=" + rowId + " settingChecked=" +
rowModel.isSelected(rowId));
}

On Aug 14, 11:15pm, Paul Turchenko <paul.turche...@gmail.com> wrote:

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#setChecked in CheckedTextView in ListView not working

by William Ferguson » Sun, 15 Aug 2010 15:26:20 GMT


 K, further info.

As could be seen from #newView, I was handling the onClick on the
CheckedTextView myself and this was because I was using a normal
Activity instead of a ListActivity.
When I switched to a ListActivity, implemented
ListActivity#onListItemClick and ditched the OnClickListener code
above I noticed 2 things.
1) The CheckedText started staying checked even after scrolling (ie it
starting to behave as expected).
2) Every time I toggle a list item, #bindView is being called once for
each visible item.

Its great that this has made it started working. But
a) I don't understand why it wasn't working before
b) 2 from above seems pretty wasteful. Why should #bindView be called
from all visible items just because one item has been checked/
unchecked?


On Aug 15, 4:29pm, William Ferguson <william.ferguson...@gmail.com>
wrote:

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#setChecked in CheckedTextView in ListView not working

by William Ferguson » Sun, 15 Aug 2010 19:15:22 GMT


 o those who may follow, if you have a list of CheckedTextView you
probably don't want the ListView to have any choice mode. Ie don't
set:
listView.setChoiceMode(ListView.CHOICE_MODE_MULTIPLE);

And then you will be able to handle the checked state in your
ListAdapter and wou will also not get #bindView fired a ridiculous
number of times.

On Aug 15, 5:26pm, William Ferguson <william.ferguson...@gmail.com>
wrote:

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#setChecked in CheckedTextView in ListView not working

by Romain Guy » Mon, 16 Aug 2010 04:22:40 GMT


 ctually you want to use CheckedTextView with choiceMode. That's what
CheckedTextView is for. However, you should not be calling setChecked
from bindView(), but let ListView handle it. The problem was that you
were doing ListView's job a second time. You don't need listeners
(click on onlistitem), calls to setChecked, etc.

On Sun, Aug 15, 2010 at 4:15 AM, William Ferguson
<william.ferguson...@gmail.com> wrote:
>



#setChecked in CheckedTextView in ListView not working

by William Ferguson » Mon, 16 Aug 2010 11:30:51 GMT


 K, there's a good chance I'm missing something but

1) I don't see anyway to configure choiceMode for a CHeckedTxtView
iether programatically or via the layout file.

2) I most definitely DO need to call #setChecked in #bindView because
otherwise the CheckedTextViews remain checked even even after the
cursor for the ListAdapter has been changed (which is possible in this
scenario via user choice). If you have a single cursor feeding your
ListAdapter you'll never notice it, but as soon as you switch between
different lists of data (and have some memory of user selection on
that data) you have to be able to set the checked value on the
CheckedTextView based upon the row and rowModel.


On Aug 16, 6:22am, Romain Guy <romain...@android.com> wrote:
> >



#setChecked in CheckedTextView in ListView not working

by Romain Guy » Mon, 16 Aug 2010 11:36:59 GMT


 gt; 1) I don't see anyway to configure choiceMode for a CHeckedTxtView

choiceMode is set on ListView, not on the CheckedTextView. For
instance:
http://d.android.com/reference/android/widget/ListView.html#setItemChecked(int,
boolean)


Use ListView's various choiceMode related methods to do this. You can

>> >



#setChecked in CheckedTextView in ListView not working

by William Ferguson » Mon, 16 Aug 2010 13:38:44 GMT


 K. We seem to be going in circles here.

If I set choiceMode on the ListView (which I was doing originally),
then you are correct in that I don'I need to setChecked on the CTV.
And in fact it just plain won't work as I said previously. There is an
Android issue that clued me into this.

However, it also means that whether an item is checked or not is held
within some internal mechanism of the ListView. This is fine (at least
you never notice that its not) as long as you never change the cursor
that is backing the CursorAdapter. If you do change the cursor using
CursorAdapater#changeCursor, then even though a new set of items get
displayed, they will be checked or not checked based upon what was
selected from the old cursor. The only way that I could see to get
ListView#choiceMode to work in this scenario would be (on change of
cursor) to call ListView#clearChoices and then iterate over all the
items in my cursor calling ListView#setItemChecked.

And since a cursor can be arbitrarily long this seemed like a really
daft way to do it. It was also a lot less clear and more code

But if I'm missing something, I'm all ears.


On Aug 16, 1:36pm, Romain Guy <romain...@android.com> wrote:
> >> >



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