Question

我想让我的用户表中的所有用户名都显示在我的微调器中以供选择，但不是显示我列表中的所有用户名，而是只显示一个来自我数据库的第一个用户..我怎样才能获得所有用户名？

   String q = "SELECT * FROM " + User.TABLE;
    Cursor cursor = dbHelper.getReadableDatabase().rawQuery(q, null);
    String[] ComRep = new String[0];
    if (cursor.moveToFirst()) {
        String rep = cursor.getString(cursor.getColumnIndex(User.KEY_username));

        do {

            ComRep = new String[]{rep};
        } while (cursor.moveToNext());

    }
    cursor.close();

    Comrep = (Spinner) findViewById(R.id.spincomrep);
    ArrayAdapter<CharSequence> adapterrep = new ArrayAdapter<CharSequence>(this, R.layout.spinner_item, ComRep);
    adapterrep.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
    Comrep.setAdapter(adapterrep);
    Comrep.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {
        @Override
        public void onItemSelected(AdapterView<?> parent, View view, int position, long id) {
            Comrep.setSelection(position);
        }

        @Override
        public void onNothingSelected(AdapterView<?> parent) {

        }
    });

提前感谢..

Answer 1

您实际上并未在数组中累积任何值。每次循环时都会创建一个新数组。

ArrayList<String> values = new ArrayList<String>();
while (cursor.moveToNext()) {
    String rep = cursor.getString(cursor.getColumnIndex(User.KEY_username));
    values.add(rep);
}
cursor.close();

ArrayAdapter<CharSequence> adapterrep = new ArrayAdapter<CharSequence>(this, R.layout.spinner_item, values.toArray(new String[values.size]));

你应该看看CursorAdapter。您可以直接从光标创建适配器，这样就不需要对循环进行编码。

如何从数据库到spinner获取数据列表

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