I have a PreferenceActivity where I have a ListPreference with three options. In my MainActivity's xml-file (activity_main.xml) I set the visibility of the Button that is selected in this ListPreference to VISIBLE.
Everything works, except for one small issue. Only after I changed the ListPreference in the settings-screen for the second time, it changes in the main-screen.
To make it more clear:
MainActivity's activity_main.xml is showed with the last saved Preference button VISIBLE and the other two GONE.activity_main (using Esc as back) nothing has changed.main_layout, the button did change (to the setting I selected in step 2).So, my question: How do I "refresh" my main_layout after a visibility has changed by a changed preference? (How to show the changes to the activity_main right away when I go back to it.)
Should I add an @Override onResume() method in the MainActivity and call some kind of "refresh" there?
Thanks in advance for the responses.
Here is my code:
MainActivity.java:
public class MainActivity extends ActionBarActivity
{
...
// Public static MainActivity so we can use findViewById from MyPrefsActivity
public static MainActivity mActivity;
public static final String LIST_PREFERENCE = "prefCheckboxOption";
public static String currentValue;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
...
SharedPreferences preferences = PreferenceManager.getDefaultSharedPreferences(getApplicationContext());
currentValue = preferences.getString(LIST_PREFERENCE, "0");
setChosenPreference(Integer.valueOf(currentValue));
mActivity = this;
}
public void setChosenPreference(int chosen_value){
// First put all Visibilities on GONE
cbButton.setVisibility(View.GONE);
spinnerButton.setVisibility(View.GONE);
popupButton.setVisibility(View.GONE);
// Then turn the chosen on VISIBLE again
switch(chosen_value){
case 0: // Multi-Click CheckBox
default:
cbButton.setVisibility(View.VISIBLE);
break;
case 1: // Dropdown CheckBox
spinnerButton.setVisibility(View.VISIBLE);
break;
case 2: // Pop-up CheckBox
popupButton.setVisibility(View.VISIBLE);
break;
}
}
...
@Override
public boolean onOptionsItemSelected(MenuItem item) {
// Handle action bar item clicks here. The action bar will
// automatically handle clicks on the Home/Up button, so long
// as you specify a parent activity in AndroidManifest.xml.
int id = item.getItemId();
switch(id){
case R.id.action_settings:
startActivity(new Intent(this, MyPrefsActivity.class));
return true;
}
return false;
}
}
MyPrefsActivity.java:
public class MyPrefsActivity extends PreferenceActivity
{
private static int prefs = R.xml.settings;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
MyPreferenceFragment pf = new MyPreferenceFragment();
getFragmentManager().beginTransaction().replace(android.R.id.content, pf).commit();
}
public static class MyPreferenceFragment extends PreferenceFragment implements OnSharedPreferenceChangeListener
{
@Override
public void onCreate(Bundle savedInstanceState){
super.onCreate(savedInstanceState);
addPreferencesFromResource(MyPrefsActivity.prefs); // outer class
// private members seem to be visible for inner class, and
// making it static made things so much easier
SharedPreferences preferences = PreferenceManager.getDefaultSharedPreferences(getActivity().getApplicationContext());
preferences.registerOnSharedPreferenceChangeListener(this);
MainActivity.mActivity.setChosenPreference(Integer.valueOf(MainActivity.currentValue));
}
@Override
public void onSharedPreferenceChanged(SharedPreferences sharedPreferences, String key) {
if(key.equals(MainActivity.LIST_PREFERENCE)){
ListPreference listPreference = (ListPreference) findPreference(key); // LIST_PREFERENCE
if(listPreference != null){
listPreference.setOnPreferenceChangeListener(new Preference.OnPreferenceChangeListener() {
@Override
public boolean onPreferenceChange(Preference preference, Object newValue) {
MainActivity.currentValue = (String) newValue;
MainActivity.mActivity.setChosenPreference(Integer.valueOf(MainActivity.currentValue));
return false;
}
});
}
else
Log.e("MyPrefsActivity", "listPreference is null!");
}
else{
// Other settings
}
}
}
}
activity_main.xml:
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:id="@+id/main_layout"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:paddingBottom="@dimen/activity_vertical_margin"
android:paddingLeft="@dimen/activity_horizontal_margin"
android:paddingRight="@dimen/activity_horizontal_margin"
android:paddingTop="@dimen/activity_vertical_margin"
android:orientation="vertical"
tools:context="com.example.testproject.MainActivity$PlaceholderFragment" >
<ImageButton
android:id="@+id/ibtnCheckbox"
android:visibility="visible"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginBottom="15dp"
android:contentDescription="@string/checkbox_content_description"
android:src="@drawable/checkbox_unchecked"
android:background="@drawable/transparent_background" />
<ImageButton
android:id="@+id/ibtnSpinner"
android:visibility="gone"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginBottom="15dp"
android:contentDescription="@string/checkbox_content_description"
android:src="@drawable/checkbox_unchecked"
android:background="@drawable/transparent_background" />
<ImageButton
android:id="@+id/ibtnPopup"
android:visibility="gone"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginBottom="15dp"
android:contentDescription="@string/checkbox_content_description"
android:src="@drawable/checkbox_unchecked"
android:background="@drawable/transparent_background" />
</LinearLayout>
settings.xml:
<?xml version="1.0" encoding="utf-8"?>
<PreferenceScreen xmlns:android="http://schemas.android.com/apk/res/android" >
<PreferenceCategory android:title="@string/checkbox_options_title" >
<ListPreference
android:key="prefCheckboxOption"
android:title="@string/pref_checkbox_option"
android:summary="@string/checkbox_options_summary"
android:entries="@array/checkbox_options"
android:entryValues="@array/checkbox_option_values" />
</PreferenceCategory>
</PreferenceScreen>
arrays.xml:
<?xml version="1.0" encoding="utf-8"?>
<resources>
<string-array name="checkbox_options">
<item>CheckBox as Multi-Click</item>
<item>CheckBox as Dropdown</item>
<item>CheckBox as Pop-up</item>
</string-array>
<string-array name="checkbox_option_values">
<item>0</item>
<item>1</item>
<item>2</item>
</string-array>
</resources>
EDIT: As reference to others:
MainActivity.java is exactly the same, except for the added onResume() method as Sir SC posted.
and MyPrefsActivity.java has changed to a much shorter version:
public class MyPrefsActivity extends PreferenceActivity
{
private static int prefs = R.xml.settings;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
getFragmentManager().beginTransaction().replace(android.R.id.content, new MyPreferenceFragment()).commit();
}
public static class MyPreferenceFragment extends PreferenceFragment
{
@Override
public void onCreate(Bundle savedInstanceState){
super.onCreate(savedInstanceState);
addPreferencesFromResource(MyPrefsActivity.prefs); // outer class
// private members seem to be visible for inner class, and
// making it static made things so much easier
}
}
}
Create an onResume() function inside your MainActivity.
Set the changes inside your onResume() function, so when you press back from the other Activity, onResume of your MainActivity will be called and the settings you write inside it will be seen.
As I understand from your example it should be like this:
@Override
protected void onResume() {
SharedPreferences preferences = PreferenceManager.getDefaultSharedPreferences(getApplicationContext());
currentValue = preferences.getString(LIST_PREFERENCE, "0");
setChosenPreference(Integer.valueOf(currentValue));
super.onResume();
}