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我有一个自定义 CursorAdapter，它从我的数据库中填充任务的 ListView。每个 ListView 项都有一个复选框和一个按钮。按下复选框时，数据库会更新以将任务设置为已完成。问题是当退出 ListActivity 并返回到 Task 列表时，什么都没有更新，并且复选框不会保留它们的状态。

我已经包含了我认为问题所在的 CursorAdapter。这可能与视图的回收有关吗？任何帮助将非常感激。

public class ScheduleListAdapter extends CursorAdapter implements 
OnClickListener, OnCheckedChangeListener
{
private final static String TAG         = "FS: ScheduleList";

private LayoutInflater      inflater    = null;
private ListView            listView    = null;

private DataManager         db          = null;
private ContentValues       values      = null;

private boolean             isCompleted = false;

public ScheduleListAdapter(Context context, Cursor c, ListView listView, DataManager db)
{
    super(context, c);

    this.listView = listView;
    this.db = db;

    // Cache the inflater, avoids asking for a new one each time
    inflater = LayoutInflater.from(context);
}

/** Determines which button is clicked **/
@Override
public void onClick(View v)
{
    final int position = listView.getPositionForView(v);

    if (position != ListView.INVALID_POSITION)
    {
        Logger.e(TAG, "Button clicked at position: " + position);
    }
}

/** Determines which star is checked **/
@Override
public void onCheckedChanged(CompoundButton buttonView, boolean isChecked)
{
    final int newValue;
    final int position = listView.getPositionForView(buttonView);

    if (position != ListView.INVALID_POSITION)
    {
        buttonView.setChecked(isChecked);

        if (isChecked)
        {
            newValue = 1;
        }
        else
        {
            newValue = 0;
        }

        values = new ContentValues();
        values.put(ScheduleTable.KEY_COMPLETED, newValue);
        db.update(ScheduleTable.TABLE_NAME, values, position);

        // refresh(db.rawQueryGetAll(ScheduleTable.TABLE_NAME));
    }
}

/** Makes a new view to hold the data pointed to by cursor. **/
@Override
public View newView(Context context, Cursor cursor, ViewGroup parent)
{
    // Create and inflate the listView item view here
    View view = inflater.inflate(R.layout.schedule_list_item, parent, false);

    ViewHolder holder = new ViewHolder();

    holder.cbxCheck = (CheckBox) view.findViewById(R.id.cbx_completed);
    holder.txvText1 = (TextView) view.findViewById(R.id.txv_taskListTitle);
    holder.txvText2 = (TextView) view.findViewById(R.id.txv_taskListSubTitle1);
    holder.txvText3 = (TextView) view.findViewById(R.id.txv_taskListSubTitle2);
    holder.btnButton = (Button) view.findViewById(R.id.btn_Edit);
    holder.btnButton.setOnClickListener(this);
    holder.cbxCheck.setOnCheckedChangeListener(this);

    view.setTag(holder);

    return view;
}

/** Bind an existing view to the data pointed to by cursor **/
@Override
public void bindView(View view, Context context, Cursor cursor)
{
    // Populate list from the cursor here
    ViewHolder holder = (ViewHolder) view.getTag();

    // Bind the data efficiently with the holder
    holder.txvText1.setText(cursor.getString(cursor.getColumnIndex(ScheduleTable.KEY_TITLE)));
    holder.txvText2.setText(cursor.getString(cursor.getColumnIndex(ScheduleTable.KEY_DESC)));
    holder.txvText3.setText(cursor.getString(cursor.getColumnIndex(ScheduleTable.KEY_DATE)));
    isCompleted = Utils.intToBool(cursor.getInt(cursor.getColumnIndex(ScheduleTable.KEY_COMPLETED)));

    holder.cbxCheck.setOnCheckedChangeListener(null);
    holder.cbxCheck.setChecked(isCompleted);
    holder.cbxCheck.setOnCheckedChangeListener(this);

    Logger.e(TAG, cursor.getString(cursor.getColumnIndex(ScheduleTable.KEY_TITLE)) + " at position is completed: " + isCompleted);
}

/** Updates the listView when data changes **/
public void refresh(Cursor newCursor)
{
    changeCursor(newCursor);
    notifyDataSetChanged();
}

private static class ViewHolder
{
    TextView    txvText1;
    TextView    txvText2;
    TextView    txvText3;
    CheckBox    cbxCheck;
    Button      btnButton;
}

}
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