我有一个更新视图,在那里我需要预先选择存储在数据库中的值为一个微调器。

我有这样的想法,但适配器没有indexOf方法,所以我被卡住了。

void setSpinner(String value)
{
    int pos = getSpinnerField().getAdapter().indexOf(value);
    getSpinnerField().setSelection(pos);
}

当前回答

如果将XML数组设置为XML布局中的旋转器,则可以做到这一点

final Spinner hr = v.findViewById(R.id.chr);
final String[] hrs = getResources().getStringArray(R.array.hours);
if(myvalue!=null){
   for (int x = 0;x< hrs.length;x++){
      if(myvalue.equals(hrs[x])){
         hr.setSelection(x);
      }
   }
}

其他回答

YourAdapter yourAdapter =
            new YourAdapter (getActivity(),
                    R.layout.list_view_item,arrData);

    yourAdapter .setDropDownViewResource(R.layout.list_view_item);
    mySpinner.setAdapter(yourAdapter );


    String strCompare = "Indonesia";

    for (int i = 0; i < arrData.length ; i++){
        if(arrData[i].getCode().equalsIgnoreCase(strCompare)){
                int spinnerPosition = yourAdapter.getPosition(arrData[i]);
                mySpinner.setSelection(spinnerPosition);
        }
    }

基于值设置微调器的一个简单方法是

mySpinner.setSelection(getIndex(mySpinner, myValue));

 //private method of your class
 private int getIndex(Spinner spinner, String myString){
     for (int i=0;i<spinner.getCount();i++){
         if (spinner.getItemAtPosition(i).toString().equalsIgnoreCase(myString)){
             return i;
         }
     }

     return 0;
 } 

复杂代码的方法已经有了,这只是简单得多。

我在Spinners中保留了一个单独的数组列表。这样我就可以在数组列表上执行indexOf,然后使用该值在Spinner中设置选择。

假设你的Spinner名为mSpinner,它包含一个选项:"some value"。

要查找并比较“some value”在Spinner中的位置,请使用以下命令:

String compareValue = "some value";
ArrayAdapter<CharSequence> adapter = ArrayAdapter.createFromResource(this, R.array.select_state, android.R.layout.simple_spinner_item);
adapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
mSpinner.setAdapter(adapter);
if (compareValue != null) {
    int spinnerPosition = adapter.getPosition(compareValue);
    mSpinner.setSelection(spinnerPosition);
}

I had the same issue when trying to select the correct item in a spinner populated using a cursorLoader. I retrieved the id of the item I wanted to select first from table 1 and then used a CursorLoader to populate the spinner. In the onLoadFinished I cycled through the cursor populating the spinner's adapter until I found the item that matched the id I already had. Then assigned the row number of the cursor to the spinner's selected position. It would be nice to have a similar function to pass in the id of the value you wish to select in the spinner when populating details on a form containing saved spinner results.

@Override
public void onLoadFinished(Loader<Cursor> loader, Cursor cursor) {  
  adapter.swapCursor(cursor);

  cursor.moveToFirst();

 int row_count = 0;

 int spinner_row = 0;

  while (spinner_row < 0 || row_count < cursor.getCount()){ // loop until end of cursor or the 
                                                             // ID is found 

    int cursorItemID = bCursor.getInt(cursor.getColumnIndexOrThrow(someTable.COLUMN_ID));

    if (knownID==cursorItemID){
    spinner_row  = row_count;  //set the spinner row value to the same value as the cursor row 

    }
cursor.moveToNext();

row_count++;

  }

}

spinner.setSelection(spinner_row ); //set the selected item in the spinner

}