Android, Autocomplettextview, force text to be from the entry list
The AutoCompleteTextView
has a method called setValidator()
that takes an instance of the interface AutoCompleteTextView.Validator
as parameter. AutoCompleteTextView.Validator
contains isValid()
with which you can check the value that has been entered, and you can "fix" this string by implementing fixText()
.
Seems this is the best you can get with AutoCompleteTextView
, as the documentation for AutoCompleteTextView.Validator
states the following:
"Since there is no foolproof way to prevent the user from leaving this View with an incorrect value in it, all we can do is try to fix it ourselves when this happens."
If your list of elements is not too long, you are probably better off using a Spinner.
****** Edit: ******
I wipped together a quick example of how you can use this, hope it helps!
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
>
<AutoCompleteTextView
android:id="@+id/input"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
/>
<EditText
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="Focus me to validate above text"/>
</LinearLayout>
-
public class AutoCompleteTextViewActivity extends Activity {
String[] validWords = new String[]{"", "snowboard", "bobsleigh", "slalom"};
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
AutoCompleteTextView view = (AutoCompleteTextView)findViewById(R.id.input);
view.setAdapter(new ArrayAdapter<String>(this, android.R.layout.simple_dropdown_item_1line, validWords));
view.setValidator(new Validator());
view.setOnFocusChangeListener(new FocusListener());
}
class Validator implements AutoCompleteTextView.Validator {
@Override
public boolean isValid(CharSequence text) {
Log.v("Test", "Checking if valid: "+ text);
Arrays.sort(validWords);
if (Arrays.binarySearch(validWords, text.toString()) > 0) {
return true;
}
return false;
}
@Override
public CharSequence fixText(CharSequence invalidText) {
Log.v("Test", "Returning fixed text");
/* I'm just returning an empty string here, so the field will be blanked,
* but you could put any kind of action here, like popping up a dialog?
*
* Whatever value you return here must be in the list of valid words.
*/
return "";
}
}
class FocusListener implements View.OnFocusChangeListener {
@Override
public void onFocusChange(View v, boolean hasFocus) {
Log.v("Test", "Focus changed");
if (v.getId() == R.id.input && !hasFocus) {
Log.v("Test", "Performing validation");
((AutoCompleteTextView)v).performValidation();
}
}
}
}