Question

我的问题是：我在我的Android应用程序上使用微调器。但是，我根本看不到微调器上显示的默认值。我可以选择元素，但我看不到微调器上的任何文本。看起来这个值是隐藏的并且没有显示任何内容，只有旋转器本身和下拉箭头。

mDbHelper = new DbAdapter(this);
    mDbHelper.open();
    cursor = mDbHelper.fetchAllBusinessCards();
    startManagingCursor(cursor);
    contactSpinner = (Spinner) findViewById(R.id.contactSpinner);

    contactSpinner.setOnItemSelectedListener(new MyOnItemSelectedListener());
    fillData();


}
public class MyOnItemSelectedListener implements OnItemSelectedListener {

    public void onItemSelected(AdapterView<?> parent,
        View view, int pos, long id) {
      Toast.makeText(parent.getContext(), "The planet is " +
          parent.getItemAtPosition(pos).toString(), Toast.LENGTH_LONG).show();
    }

    public void onNothingSelected(AdapterView parent) {
      // Do nothing.
    }
}

private void fillData() {



/*Create an array to specify the fields we want to display in the list (only the 'colourName' column in this case) */

String[] from = new String[]{DbAdapter.getKeyTitle() }; 
/* and an array of the fields we want to bind those fields to (in this case just the textView 'tvDBViewRow' from our new db_view_row.xml layout above) */
int[] to = new int[]{R.id.tvDBViewRow};

/* Now create a simple cursor adapter.. */ 
SimpleCursorAdapter colourAdapter =
new SimpleCursorAdapter(this,R.layout.db_view_row, cursor, from, to);

/* and assign it to our Spinner widget */ 
contactSpinner.setAdapter(colourAdapter);
//contactSpinner.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
contactSpinner.setSelection(0);

}

@Override
protected void onDestroy() {
    super.onDestroy();
    if (mDbHelper != null) {
        mDbHelper.close();
    }
}

}

Answer 1

您可以调用spinner.setSelection来设置当前的状态任何你想要的旋转器。这肯定有效

spinner.setSelection(0);

但你也必须打电话 setDropDownViewResource（）

让我们说

adapter.setDropDownViewResource(
android.R.layout.simple_spinner_dropdown_item);

如何在微调器上看到一个值？

1 个答案: