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);
}
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
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);
}
其他回答
为了让应用程序记住最后选择的微调值,你可以使用下面的代码:
Below code reads the spinner value and sets the spinner position accordingly. public class MainActivity extends Activity { @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); int spinnerPosition; Spinner spinner1 = (Spinner) findViewById(R.id.spinner1); ArrayAdapter<CharSequence> adapter1 = ArrayAdapter.createFromResource( this, R.array.ccy_array, android.R.layout.simple_spinner_dropdown_item); adapter1.setDropDownViewResource(android.R.layout.simple_list_item_activated_1); // Apply the adapter to the spinner spinner1.setAdapter(adapter1); // changes to remember last spinner position spinnerPosition = 0; String strpos1 = prfs.getString("SPINNER1_VALUE", ""); if (strpos1 != null || !strpos1.equals(null) || !strpos1.equals("")) { strpos1 = prfs.getString("SPINNER1_VALUE", ""); spinnerPosition = adapter1.getPosition(strpos1); spinner1.setSelection(spinnerPosition); spinnerPosition = 0; } And put below code where you know latest spinner values are present, or somewhere else as required. This piece of code basically writes the spinner value in SharedPreferences. Spinner spinner1 = (Spinner) findViewById(R.id.spinner1); String spinlong1 = spinner1.getSelectedItem().toString(); SharedPreferences prfs = getSharedPreferences("WHATEVER", Context.MODE_PRIVATE); SharedPreferences.Editor editor = prfs.edit(); editor.putString("SPINNER1_VALUE", spinlong1); editor.commit();
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
}
你必须传递你的自定义适配器的位置,如REPEAT[position]。它能正常工作。
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);
}
}
}
因为我需要一些东西,这也适用于本地化,我想出了以下两种方法:
private int getArrayPositionForValue(final int arrayResId, final String value) {
final Resources english = Utils.getLocalizedResources(this, new Locale("en"));
final List<String> arrayValues = Arrays.asList(english.getStringArray(arrayResId));
for (int position = 0; position < arrayValues.size(); position++) {
if (arrayValues.get(position).equalsIgnoreCase(value)) {
return position;
}
}
Log.w(TAG, "getArrayPosition() --> return 0 (fallback); No index found for value = " + value);
return 0;
}
如您所见,我还遇到了arrays.xml和我要比较的值之间的大小写敏感性的额外复杂性。 如果你没有这个,上面的方法可以简化为:
返回arrayValues.indexOf(价值);
静态助手方法
public static Resources getLocalizedResources(Context context, Locale desiredLocale) {
Configuration conf = context.getResources().getConfiguration();
conf = new Configuration(conf);
conf.setLocale(desiredLocale);
Context localizedContext = context.createConfigurationContext(conf);
return localizedContext.getResources();
}