Question

我正在尝试使用游标编写搜索查询。它总是将游标返回为空。该查询应该返回我正在搜索的文本的项目列表（String [] selectionArgs = {inputText};）。其中inputText是我正在搜索的搜索词。

        Uri uri = ContactsContract.CommonDataKinds.Phone.CONTENT_URI;
        String[] projection    = new String[] {ContactsContract.Contacts._ID, ContactsContract.CommonDataKinds.Phone.DISPLAY_NAME,
                ContactsContract.CommonDataKinds.Phone.NUMBER};
        String selection = ContactsContract.CommonDataKinds.Phone.DISPLAY_NAME + " = ? ";
        String[] selectionArgs = { inputText };

        // Expecting problem in the query.
        Cursor people = getContentResolver().query(uri, projection, selection, selectionArgs, null);

        int indexName = people.getColumnIndex(StructuredName.DISPLAY_NAME);
        int indexNumber = people.getColumnIndex(ContactsContract.CommonDataKinds.Phone.NUMBER);
        int idIdx = people.getColumnIndexOrThrow(PhoneLookup._ID);

        if(!people.moveToFirst())
        {
            Log.w("No Cursor.., ","No cursor.., Cursor is empty..");
        }

        do {
            String id = people.getString(idIdx);
            String name   = people.getString(indexName);
            String number = people.getString(indexNumber);
            // Do work...
        } while (people.moveToNext());

        return people;

它返回以下错误。

W/No Cursor.., ( 1303): No cursor.., Cursor is empty..

W/Filter  ( 1303): An exception occured during performFiltering()!
W/Filter  ( 1303): android.database.CursorIndexOutOfBoundsException: Index 0 requested, with a size of 0
W/Filter  ( 1303):      at android.database.AbstractCursor.checkPosition(AbstractCursor.java:580)
W/Filter  ( 1303):      at android.database.AbstractWindowedCursor.checkPosition(AbstractWindowedCursor.java:214)
W/Filter  ( 1303):      at android.database.AbstractWindowedCursor.getString(AbstractWindowedCursor.java:41)
W/Filter  ( 1303):      at android.database.CursorWrapper.getString(CursorWrapper.java:135)
W/Filter  ( 1303):      at rebornlabs.sms2india.sms.app.ContactActivity.getSearchedContacts(ContactActivity.java:179)
W/Filter  ( 1303):      at rebornlabs.sms2india.sms.app.ContactActivity$3.runQuery(ContactActivity.java:102)
W/Filter  ( 1303):      at android.widget.CursorAdapter.runQueryOnBackgroundThread(CursorAdapter.java:309)
W/Filter  ( 1303):      at android.widget.CursorFilter.performFiltering(CursorFilter.java:49)
W/Filter  ( 1303):      at android.widget.Filter$RequestHandler.handleMessage(Filter.java:234)
W/Filter  ( 1303):      at android.os.Handler.dispatchMessage(Handler.java:99)
W/Filter  ( 1303):      at android.os.Looper.loop(Looper.java:123)
W/Filter  ( 1303):      at android.os.HandlerThread.run(HandlerThread.java:60)

我期待查询中出现一些问题..不知道我错过了什么。

Cursor people = getContentResolver().query(uri, projection, selection, selectionArgs, null);

Answer 1

如果你想根据部分结果进行搜索（如搜索“他”将给出结果“Hello”，“He-man”，“Heavy”，“Te He he”等等，你应该使用LIKE代替a =？陈述

离。

String[] projection = new String[] {
   ContactsContract.Contacts._ID, 
   ContactsContract.CommonDataKinds.Phone.DISPLAY_NAME,
   ContactsContract.CommonDataKinds.Phone.NUMBER 
};
String selection = ContactsContract.CommonDataKinds.Phone.DISPLAY_NAME + " like '%" + inputText + "%'";

Cursor people = getContentResolver().query(uri, projection, selection, null, null);

类似的语句不能与selectionArgs一起使用，这就是我为它们传递null的原因..

此外，您需要更改代码流。如果您的光标不包含条目，您仍在尝试从光标中检索值。尝试这样的事情..

while(people.moveToNext()) {
        String id = people.getString(idIdx);
        String name   = people.getString(indexName);
        String number = people.getString(indexNumber);
        // Do work...
    }

您可以删除if (!people.moveToFirst())语句，因为它除了打印日志语句之外什么都不做。 while语句将执行相同的检查，并仅将数据分配给列表（如果存在）

实现搜索查询时，Cursor始终返回为空

1 个答案: