此问题Android: Wrong item checked when filtering listview中讨论了此问题。总结该问题，当使用带有CursorAdapter和过滤器的列表视图时，在过滤后的列表中选择的项目将在删除过滤器后丢失其选择，而是选择未过滤列表中该位置的项目。
使用上面链接问题中的代码示例，我们应该在哪里放置代码来标记复选框。我相信它应该在CustomCursorAdapter的getView（）方法中，但我不确定。另外，我们如何访问包含自定义适配器类中所有selectedIds的HashSet，因为它将在保存列表的主活动中初始化和修改。
我实施ListView的活动
@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://stackoverflow.com/questions/1737009/how-to-make-a-nice-looking-listview-filter-on-android
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://stackoverflow.com/questions/2002607/android-how-to-text-filter-a-listview-based-on-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);
}
我的自定义光标适配器：
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;
}
}
答案 0 :(得分：1)
我做了什么解决了它：
cur = cursor。 c = simplecursoradapter内部游标。
我的MainActivity中的：
(members)
static ArrayList<Boolean> checkedStates = new ArrayList<Boolean>();
static HashSet<String> selectedIds = new HashSet<String>();
static HashSet<Integer> selectedLines = new HashSet<Integer>();
：
if (!selectedIds.contains(bookmarkID)) {
selectedIds.add(bookmarkID);
selectedLines.add(position);
} else {
selectedIds.remove(bookmarkID);
selectedLines.remove(position);
if (selectedIds.isEmpty()) {
//clear everything
selectedIds.clear();
checkedStates.clear();
selectedLines.clear();
//refill checkedStates to avoid force close bug - out of bounds
if (cur.moveToFirst()) {
while (!cur.isAfterLast()) {
MainActivity.checkedStates.add(false);
cur.moveToNext();
}
}
}
在我添加的SimpleCursorAdapter中（都在getView中）：
// fill the checkedStates array with amount of bookmarks (prevent OutOfBounds Force close)
if (c.moveToFirst()) {
while (!c.isAfterLast()) {
MainActivity.checkedStates.add(false);
c.moveToNext();
}
}
和
String bookmarkID = c.getString(0);
CheckedTextView markedItem = (CheckedTextView) row.findViewById(R.id.btitle);
if (MainActivity.selectedIds.contains(new String(bookmarkID))) {
markedItem.setChecked(true);
MainActivity.selectedLines.add(pos);
} else {
markedItem.setChecked(false);
MainActivity.selectedLines.remove(pos);
}
希望这会有所帮助......你当然需要根据自己的需要进行调整。
修改
下载的FB SDK，无法通过FB登录。你有一个错误，如果在设备上安装了FB应用程序，你就无法获得有效的access_token。删除了FB应用程序，并在getFriends()中获得了一个FC。通过用runOnUiThread(new Runnable...)包装其范围来解决它。
你得到的错误与糟糕的过滤，错误的复选框状态无关......你得到它，因为你在查询之前尝试访问游标（已经关闭）。 在适配器使用之前，您似乎正在关闭光标。通过添加：
验证它mDbHelper = new FriendsDbAdapter(context);
mDbHelper.open() ;
cursor = mDbHelper.fetchAllFriends();
到SelectFriendsAdapter中的getView范围。
添加后，它不会FC，你可以开始照顾你的过滤器。
确保光标未关闭，基本上如果您使用startManagingCursor()进行管理，则无需手动关闭它。
希望你能从这里拿走它！
答案 1 :(得分：0)
adapter.setFilterQueryProvider(new FilterQueryProvider() {
public Cursor runQuery(CharSequence constraint) {
return db.fetchdatabyfilter(constraint.toString(), "name");
}
});