Using a simple EditTextPreference in my preferences activity:
<EditTextPreference
android:key="SomeKey"
android:title="@string/some_title"
android:summary="..."
android:numeric="integer"
android:maxLength="2"
/>
Is there a way that this configuration value would be saved as integer? Seems now it just allows to enter numbers, but the value is still saved as string:
Calling:
SharedPreferences preferences = PreferenceManager.getDefaultSharedPreferences(this);
int value = preferences.getInt("SomeKey", -1);
throws me java.lang.ClassCastException: java.lang.String , and:
SharedPreferences preferences = PreferenceManager.getDefaultSharedPreferences(this);
String value = preferences.getString("SomeKey", "-1");
retrieves the value successfully.
How to make PreferenceActivity to save value as integer by default?
Source: Tips4all
You could extend EditTextPreference:
ReplyDeletepublic class IntEditTextPreference extends EditTextPreference {
public IntEditTextPreference(Context context) {
super(context);
}
public IntEditTextPreference(Context context, AttributeSet attrs) {
super(context, attrs);
}
public IntEditTextPreference(Context context, AttributeSet attrs, int defStyle) {
super(context, attrs, defStyle);
}
@Override
protected String getPersistedString(String defaultReturnValue) {
return String.valueOf(getPersistedInt(-1));
}
@Override
protected boolean persistString(String value) {
return persistInt(Integer.valueOf(value));
}
}
It would be better to overwrite onSetInitialValue() and setText() methods, but then you would have to copy some code from a base class. Above solution is simplier, but it's quite tricky - "string" methods do something with ints. Try to not extend this class further ;-)
You could use it from XML by:
<package.name.IntEditTextPreference
android:key="SomeKey"
android:title="@string/some_title"
android:summary="..."
android:numeric="integer"
android:maxLength="2"
/>
Tested, works :-)
Even if you set android:numeric="integer" it'll be text preference - as its name suggest. You could easily convert string value to int using Integer.valueOf(). Also you could overwrite PreferenceActivity to do conversion automatically on exit.
ReplyDeleteI think the best solution is to write simple method to get this value from preferences. Something like:
public static int getSomePref(Context context) {
SharedPreferences prefs =
PreferenceManager.getDefaultSharedPreferences(context);
String value = prefs.getString("SomeKey", null);
return value == null ? -1 : Integer.valueOf(value);
}
Then you could very easily use it from your code.