I found the solution on my own. I used a small work-around of all this nested PreferenceScreen's. I simply made a separation to different xml-preference files, created an additional Fragment which extends PreferenceFragment and there I show an appropriate nested preference screen.
Maybe somebody would found this useful.
Github sources link.
Some code examples below:
main_preferences.xml
<?xml version="1.0" encoding="utf-8"?>
<PreferenceScreen xmlns:android="http://schemas.android.com/apk/res/android" >
<PreferenceCategory android:title="Main category" >
<EditTextPreference
android:defaultValue="defaultValue"
android:key="key_global_setting"
android:title="Global title" />
</PreferenceCategory>
<PreferenceCategory android:title="Nested screens" >
<Preference
android:key="NESTED_KEY1"
android:persistent="false"
android:title="Nested screen #1" />
<Preference
android:key="NESTED_KEY2"
android:persistent="false"
android:title="Nested screen #2" />
</PreferenceCategory>
</PreferenceScreen>
nested_screen1_preferences.xml
<?xml version="1.0" encoding="utf-8"?>
<PreferenceScreen xmlns:android="http://schemas.android.com/apk/res/android"
android:title="Nested screen #1" >
<CheckBoxPreference
android:defaultValue="false"
android:key="nested_screen_1_1"
android:title="Nested screen 1.1 check box" />
<CheckBoxPreference
android:defaultValue="true"
android:key="nested_screen_1_2"
android:title="Nested screen 1.2 check box" />
</PreferenceScreen>
nested_screen2_preferences.xml
<?xml version="1.0" encoding="utf-8"?>
<PreferenceScreen xmlns:android="http://schemas.android.com/apk/res/android"
android:title="Nested screen #2">
<CheckBoxPreference
android:defaultValue="true"
android:key="nested_screen2"
android:title="Nested screen 2 check box" />
</PreferenceScreen>
SettingsActivity.java
public class SettingsActivity extends ActionBarActivity implements MyPreferenceFragment.Callback {
private static final String TAG_NESTED = "TAG_NESTED";
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_settings);
Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
if (toolbar != null) {
setSupportActionBar(toolbar);
getSupportActionBar().setDisplayHomeAsUpEnabled(true);
}
if (savedInstanceState == null) {
getFragmentManager().beginTransaction()
.add(R.id.contentSettings, new MyPreferenceFragment())
.commit();
}
}
@Override
public void onBackPressed() {
// this if statement is necessary to navigate through nested and main fragments
if (getFragmentManager().getBackStackEntryCount() == 0) {
super.onBackPressed();
} else {
getFragmentManager().popBackStack();
}
}
@Override
public void onNestedPreferenceSelected(int key) {
getFragmentManager().beginTransaction().replace(R.id.contentSettings, NestedPreferenceFragment.newInstance(key), TAG_NESTED).addToBackStack(TAG_NESTED).commit();
}
}
MyPreferenceFragment.java
// The main preference fragment class
public class MyPreferenceFragment extends PreferenceFragment implements Preference.OnPreferenceClickListener {
private Callback mCallback;
private static final String KEY_1 = "NESTED_KEY1";
private static final String KEY_2 = "NESTED_KEY2";
@Override
public void onAttach(Activity activity) {
super.onAttach(activity);
if (activity instanceof Callback) {
mCallback = (Callback) activity;
} else {
throw new IllegalStateException("Owner must implement Callback interface");
}
}
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
// Load the preferences from an XML resource
addPreferencesFromResource(R.xml.main_preferences);
// add listeners for non-default actions
Preference preference = findPreference(KEY_1);
preference.setOnPreferenceClickListener(this);
preference = findPreference(KEY_2);
preference.setOnPreferenceClickListener(this);
}
@Override
public boolean onPreferenceClick(Preference preference) {
// here you should use the same keys as you used in the xml-file
if (preference.getKey().equals(KEY_1)) {
mCallback.onNestedPreferenceSelected(NestedPreferenceFragment.NESTED_SCREEN_1_KEY);
}
if (preference.getKey().equals(KEY_2)) {
mCallback.onNestedPreferenceSelected(NestedPreferenceFragment.NESTED_SCREEN_2_KEY);
}
return false;
}
public interface Callback {
public void onNestedPreferenceSelected(int key);
}
}
NestedPreferencesFragment.java
public class NestedPreferenceFragment extends PreferenceFragment {
public static final int NESTED_SCREEN_1_KEY = 1;
public static final int NESTED_SCREEN_2_KEY = 2;
private static final String TAG_KEY = "NESTED_KEY";
public static NestedPreferenceFragment newInstance(int key) {
NestedPreferenceFragment fragment = new NestedPreferenceFragment();
// supply arguments to bundle.
Bundle args = new Bundle();
args.putInt(TAG_KEY, key);
fragment.setArguments(args);
return fragment;
}
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
checkPreferenceResource();
}
private void checkPreferenceResource() {
int key = getArguments().getInt(TAG_KEY);
// Load the preferences from an XML resource
switch (key) {
case NESTED_SCREEN_1_KEY:
addPreferencesFromResource(R.xml.nested_screen1_preferences);
break;
case NESTED_SCREEN_2_KEY:
addPreferencesFromResource(R.xml.nested_screen2_preferences);
break;
default:
break;
}
}
}
