java - 实现自己的 Android CursorAdapter 用于搜索建议 - 未知异常

Question

我已经实现了自己的光标适配器来手动处理建议，这样我就可以摆脱android文档提出的过度杀伤方法。 基本上我所做的就是在操作栏搜索 View 膨胀后将其 setOnQueryTextListener 。每次用户输入新的搜索文本时，我都会查询返回游标的 Sqlite 数据库。最后，我使用检索到的游标创建自己的游标适配器，并使用 setSuggestionsAdapter 方法将其设置为 searchview。 这里的问题是，我收到许多未知的异常，具体取决于每次配置更改时更新光标的方式。我稍后再解释，首先是一些代码:

************************ 我自己的光标适配器类 ****************** ******

公共(public)类 BusStopCursorAdapter 扩展 CursorAdapter {

public BusStopCursorAdapter(Context context, Cursor cursor) {
    super(context, cursor, false);

}

@Override
public void bindView(View view, Context context, Cursor cursor) {

    //set address
    ((TextView)view.findViewById(R.id.address)).setText(cursor.getString(1));
    //set line
    ((TextView)view.findViewById(R.id.line)).setText(cursor.getString(2));

}

@Override
public View newView(Context context, Cursor cursor, ViewGroup parent) {

    LayoutInflater inflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);

    View view = inflater.inflate(R.layout.suggestions_layout, parent, false);

    //set address
    ((TextView)view.findViewById(R.id.address)).setText(cursor.getString(1));
    //set line
    ((TextView)view.findViewById(R.id.line)).setText(cursor.getString(2));


    return view;

}
}

************************ 监听器添加到 searchView ****************** *

        // Associate searchView listeners
        searchView.setOnQueryTextListener(new SearchView.OnQueryTextListener() {

        @Override
        public boolean onQueryTextSubmit(String query) {

            return false;
        }

        @Override
        public boolean onQueryTextChange(String newText) {
            System.out.println("QUERY STRING: "+newText);
            Cursor cursor = queryData(newText);
            searchView.setSuggestionsAdapter(new BusStopCursorAdapter(getBaseContext(), cursor));

            return true;
        }
    });

在这种情况下，我更新光标所做的就是大幅添加一个全新的适配器。起初一切都很顺利，但是当配置发生更改时，我收到以下日志:

03-10 15:20:11.762    1927-1927/com.nikkis.vallabus I/System.out﹕ QUERY STRING: ad
03-10 15:20:13.012    1927-1927/com.nikkis.vallabus I/System.out﹕ QUERY STRING: ado
03-10 15:20:13.992    1927-1927/com.nikkis.vallabus I/System.out﹕ QUERY STRING: adol
03-10 15:20:15.602    1927-1927/com.nikkis.vallabus I/System.out﹕ QUERY STRING:
03-10 15:20:15.602    1927-1927/com.nikkis.vallabus I/System.out﹕ QUERY STRING: adol
03-10 15:20:15.662    1927-1927/com.nikkis.vallabus W/IInputConnectionWrapper﹕ showStatusIcon on inactive InputConnection
03-10 15:20:15.672    1927-1927/com.nikkis.vallabus W/IInputConnectionWrapper﹕ getExtractedText on inactive InputConnection
03-10 15:20:15.722    1927-1927/com.nikkis.vallabus W/IInputConnectionWrapper﹕ getTextBeforeCursor on inactive InputConnection
03-10 15:20:15.812    1927-1927/com.nikkis.vallabus W/IInputConnectionWrapper﹕ getTextBeforeCursor on inactive InputConnection
03-10 15:20:15.882    1927-1927/com.nikkis.vallabus W/IInputConnectionWrapper﹕ getExtractedText on inactive InputConnection
03-10 15:20:18.402    1927-1927/com.nikkis.vallabus I/System.out﹕ QUERY STRING:
03-10 15:20:18.402    1927-1927/com.nikkis.vallabus I/System.out﹕ QUERY STRING: adol
03-10 15:20:18.492    1927-1927/com.nikkis.vallabus W/IInputConnectionWrapper﹕ showStatusIcon on inactive InputConnection
03-10 15:20:18.492    1927-1927/com.nikkis.vallabus W/IInputConnectionWrapper﹕ getExtractedText on inactive InputConnection
03-10 15:20:18.522    1927-1927/com.nikkis.vallabus W/IInputConnectionWrapper﹕ getTextBeforeCursor on inactive InputConnection
03-10 15:20:18.552    1927-1927/com.nikkis.vallabus W/IInputConnectionWrapper﹕ getTextBeforeCursor on inactive InputConnection
03-10 15:20:18.592    1927-1927/com.nikkis.vallabus W/IInputConnectionWrapper﹕ getExtractedText on inactive InputConnection

该应用程序似乎运行良好。唯一无法解释的问题(可能与这些异常有关)是，在配置更改后，有时会出现建议，有时则不会。就像它无法执行查询或其他操作一样。

例如，如果我使用这个替代监听器实现，它只更新游标(因为它应该是最干净的方式)而不是重新创建整个适配器，那么事情会变得更糟:我收到未知的 SQL 错误(该错误不应该出现，因为sql 查询工作完美)，某种游标列访问错误(在显示建议时不应该出现)，并且应用程序最终崩溃。

**************************** 另类监听器******************** **************

        @Override
        public boolean onQueryTextChange(String newText) {
            System.out.println("QUERY STRING: "+newText);
            Cursor cursor = queryData(newText);
         /*   if (newText !="")
            searchView.setSuggestionsAdapter(new BusStopCursorAdapter(getBaseContext(), cursor));*/

            if (searchView.getSuggestionsAdapter() == null) {
                searchView.setSuggestionsAdapter(new BusStopCursorAdapter(getBaseContext(), cursor));
            } else {
                searchView.getSuggestionsAdapter().changeCursor(cursor);
            }

            return true;
        }

******************************** 崩溃日志**************** ******************

03-10 15:58:46.762    3767-3767/com.nikkis.vallabus  W/IInputConnectionWrapper﹕ getTextBeforeCursor on inactive InputConnection
03-10 15:58:46.792    3767-3767/com.nikkis.vallabus W/IInputConnectionWrapper﹕ getExtractedText on inactive InputConnection
03-10 15:58:48.612    3767-3767/com.nikkis.vallabus I/System.out﹕ QUERY STRING:
03-10 15:58:48.622    3767-3767/com.nikkis.vallabus I/System.out﹕ QUERY STRING: adol
03-10 15:58:48.632    3767-4304/com.nikkis.vallabus W/Filter﹕ An exception occured during performFiltering()!
java.lang.IllegalStateException: attempt to re-open an already-closed object: SQLiteQuery: SELECT stop.stopID AS _id, stop.address, stop_line.line FROM stop_line, stop WHERE stop.stopID = stop_line.stop AND stop.address LIKE '%%';
        at android.database.sqlite.SQLiteClosable.acquireReference(SQLiteClosable.java:55)
        at android.database.sqlite.SQLiteQuery.fillWindow(SQLiteQuery.java:58)
        at android.database.sqlite.SQLiteCursor.fillWindow(SQLiteCursor.java:143)
        at android.database.sqlite.SQLiteCursor.getCount(SQLiteCursor.java:133)
        at android.widget.CursorFilter.performFiltering(CursorFilter.java:53)
        at android.widget.Filter$RequestHandler.handleMessage(Filter.java:234)
        at android.os.Handler.dispatchMessage(Handler.java:99)
        at android.os.Looper.loop(Looper.java:213)
        at android.os.HandlerThread.run(HandlerThread.java:60)
03-10 15:58:48.652    3767-3767/com.nikkis.vallabus W/IInputConnectionWrapper﹕ showStatusIcon on inactive InputConnection
03-10 15:58:48.652    3767-3767/com.nikkis.vallabus W/IInputConnectionWrapper﹕ getExtractedText on inactive InputConnection
03-10 15:58:48.652    3767-4304/com.nikkis.vallabus E/CursorWindow﹕ Failed to read row 0, column 0 from a CursorWindow which has 1 rows, 0 columns.
03-10 15:58:48.702    3767-3767/com.nikkis.vallabus W/IInputConnectionWrapper﹕ getTextBeforeCursor on inactive InputConnection
03-10 15:58:48.792    3767-3767/com.nikkis.vallabus W/IInputConnectionWrapper﹕ getTextBeforeCursor on inactive InputConnection
03-10 15:58:48.832    3767-3767/com.nikkis.vallabus W/IInputConnectionWrapper﹕ getExtractedText on inactive InputConnection

我希望得到一些帮助，因为在花费数小时的搜索后我完全陷入困境。提前致谢。

Answer 1

你把这个搞得太复杂了:不需要setOnQueryTextListener，只需调用:

myCursorAdapter.setFilterQueryProvider(this);
searchView.setSuggestionsAdapter(myCursorAdapter);

在onCreateOptionsMenu中，您将需要您的Activity来实现FilterQueryProvider，其中在其runQuery中返回您的Cursor有建议