This problem is discussed in this question Android: Wrong item checked when filtering listview. To summarize the problem, when using a listview with a CursorAdapter and a filter, items selected on a filtered list lose their selection after the filter is removed and instead, items at that position in the unfiltered list get selected.
Using the code sample in the linked question above, where should we put the code to mark the checkboxes. I believe it should be in the getView() method of the CustomCursorAdapter, but I am not sure. Also, how do we access the HashSet holding all the selectedIds in the custom adapter class, because it will be initialized and modified in the main activity holding the list.
My activity implementing the ListView
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.selectfriends);
Log.v(TAG, "onCreate called") ;
selectedIds = new ArrayList<String>() ;
selectedLines = new ArrayList<Integer>() ;
mDbHelper = new FriendsDbAdapter(this);
mDbHelper.open() ;
Log.v(TAG, "database opened") ;
Cursor c = mDbHelper.fetchAllFriends();
startManagingCursor(c);
Log.v(TAG, "fetchAllFriends Over") ;
String[] from = new String[] {mDbHelper.KEY_NAME};
int[] to = new int[] { R.id.text1 };
final ListView listView = getListView();
Log.d(TAG, "Got listView");
// Now initialize the adapter and set it to display using our row
adapter =
new FriendsSimpleCursorAdapter(this, R.layout.selectfriendsrow, c, from, to);
Log.d(TAG, "we have got an adapter");
// Initialize the filter-text box
//Code adapted from https://mcmap.net/q/150299/-how-to-dynamically-update-a-listview-on-android-closed
filterText = (EditText) findViewById(R.id.filtertext) ;
filterText.addTextChangedListener(filterTextWatcher) ;
/* Set the FilterQueryProvider, to run queries for choices
* that match the specified input.
* Code adapted from https://mcmap.net/q/507493/-how-to-text-filter-an-android-listview-backed-by-a-simplecursoradapter
*/
adapter.setFilterQueryProvider(new FilterQueryProvider() {
public Cursor runQuery(CharSequence constraint) {
// Search for friends whose names begin with the specified letters.
Log.v(TAG, "runQuery Constraint = " + constraint) ;
String selection = mDbHelper.KEY_NAME + " LIKE '%"+constraint+"%'";
mDbHelper.open();
Cursor c = mDbHelper.fetchFriendsWithSelection(
(constraint != null ? constraint.toString() : null));
return c;
}
});
setListAdapter(adapter);
Log.d(TAG, "setListAdapter worked") ;
listView.setItemsCanFocus(false);
listView.setChoiceMode(ListView.CHOICE_MODE_MULTIPLE);
// listView.setOnItemClickListener(mListener);
Button btn;
btn = (Button)findViewById(R.id.buttondone);
mDbHelper.close();
}
@Override
protected void onListItemClick(ListView parent, View v, int position, long id) {
String item = (String) getListAdapter().getItem(position);
Toast.makeText(this, item + " selected", Toast.LENGTH_LONG).show();
//gets the Bookmark ID of selected position
Cursor cursor = (Cursor)parent.getItemAtPosition(position);
String bookmarkID = cursor.getString(0);
Log.d(TAG, "mListener -> bookmarkID = " + bookmarkID);
Log.d(TAG, "mListener -> position = " + position);
// 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);
}
}
private TextWatcher filterTextWatcher = new TextWatcher() {
public void afterTextChanged(Editable s) {
}
public void beforeTextChanged(CharSequence s, int start, int count, int after) {
}
public void onTextChanged(CharSequence s, int start, int before, int count) {
Log.v(TAG, "onTextChanged called. s = " + s);
adapter.getFilter().filter(s);
}
};
@Override
protected void onDestroy() {
super.onDestroy();
filterText.removeTextChangedListener(filterTextWatcher);
}
My Custom Cursor Adapter:
public class FriendsSimpleCursorAdapter extends SimpleCursorAdapter implements Filterable {
private static final String TAG = "FriendsSimpleCursorAdapter";
private final Context context ;
private final String[] values ;
private final int layout ;
private final Cursor cursor ;
static class ViewHolder {
public CheckedTextView checkedText ;
}
public FriendsSimpleCursorAdapter(Context context, int layout, Cursor c,
String[] from, int[] to) {
super(context, layout, c, from, to);
this.context = context ;
this.values = from ;
this.layout = layout ;
this.cursor = c ;
Log.d(TAG, "At the end of the constructor") ;
}
@Override
public View getView(int position, View convertView, ViewGroup parent) {
Log.d(TAG, "At the start of rowView. position = " + position) ;
View rowView = convertView ;
if(rowView == null) {
Log.d(TAG, "rowView = null");
try {
LayoutInflater inflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
rowView = inflater.inflate(layout, parent, false);
Log.d(TAG, "rowView inflated. rowView = " + rowView);
ViewHolder viewHolder = new ViewHolder() ;
viewHolder.checkedText = (CheckedTextView) rowView.findViewById(R.id.text1) ;
rowView.setTag(viewHolder);
}
catch (Exception e) {
Log.e(TAG, "exception = " + e);
}
}
ViewHolder holder = (ViewHolder) rowView.getTag();
int nameCol = cursor.getColumnIndex(FriendsDbAdapter.KEY_NAME) ;
String name = cursor.getString(nameCol);
holder.checkedText.setText(name);
Log.d(TAG, "At the end of rowView");
return rowView;
}
}