I am new to Android development. I am trying to populate a spinner by using the SimpleAdapter. But spinner's list is showing blank element. When I click any element, its text is shown properly in Toast. Please tell me what is the problem in my code below.
public void onCreate(Bundle savedInstanceState) {
private List<Map<String, String>> data = new ArrayList<Map<String, String>>();
String[] from = new String[] { "colorsData" };
int[] to = new int[] { R.id.spinner };
String[] colors = getResources().getStringArray(R.array.colorsData);
for (int i = 0; i < colors.length; i++) {
data.add(addData(colors[i]));
}
Spinner spinner = (Spinner) findViewById(R.id.spinner);
SimpleAdapter simpleAdapter = new SimpleAdapter(this, data, android.R.layout.simple_spinner_item, from, to);
simpleAdapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
spinner.setAdapter(simpleAdapter);
spinner.setOnItemSelectedListener(new OnItemSelectedListener() {
@Override
public void onItemSelected开发者_开发技巧(AdapterView<?> parent, View view,
int position, long id) {
Toast.makeText(
parent.getContext(),
"Selected Color:- "
+ parent.getItemAtPosition(position),
Toast.LENGTH_LONG).show();
}
});
}
private Map<String, String> addData(String colorName) {
Map<String, String> mapList = new HashMap<String, String>();
mapList.put("colorsData", colorName);
return mapList;
}
I'm about 95% sure that your to
array should be declared as:
int[] to = new int[] { android.R.id.text1 };
Give that a try.
EDIT (based on comments below):
It seems there was a bug in older versions of AndroidOS which caused that IllegalStateException. (I didn't see the exception in 2.2, but I did see it in 1.5 in the emulator.) The bug can be worked around by adding a ViewBinder to the SimpleAdapter. ViewBinder isn't hard to implement; here's an example:
SimpleAdapter.ViewBinder viewBinder = new SimpleAdapter.ViewBinder() {
public boolean setViewValue(View view, Object data,
String textRepresentation) {
// We configured the SimpleAdapter to create TextViews (see
// the 'to' array), so this cast should be safe:
TextView textView = (TextView) view;
textView.setText(textRepresentation);
return true;
}
};
simpleAdapter.setViewBinder(viewBinder);
I blogged about this here.
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