Can't get PreferenceFragmentCompat to work
I am trying to create an Activity that extends AppCompatActivity and has two fragments inside of it (one below another - just by using a LinearLayout). I would like the first fragment to extend the PreferenceFragmentCompat class from the support-v7 library.
I followed Google's short example regarding PreferenceFragmentCompat as shown at https://developer.android.com/reference/android/support/v7/preference/PreferenceFragmentCompat.html.
Here is my current code:
GroupDetailsActivity.java
public class GroupDetailsActivity extends AppCompatActivity {
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_group_details);
GroupDetailsPrefFragment prefFragment = GroupDetailsPrefFragment.newInstance();
GroupDetailsMembersFragment membersFragment = GroupDetailsMembersFragment.newInstance();
FragmentManager fm = getSupportFragmentManager();
fm.beginTransaction()
.add(R.id.flPrefFragment, prefFragment, GroupDetailsPrefFragment.TAG)
.add(R.id.flMembersFragment, membersFragment, GroupDetailsMembersFragment.TAG)
.commit();
}
}
GroupDetailsPrefFragment .java - The problematic fragment
public class GroupDetailsPrefFragment extends PreferenceFragmentCompat {
public static final String TAG = "GroupDetailsPrefFragment";
@Override
public void onCreatePreferences(Bundle bundle, String s) {
setPreferencesFromResource(R.xml.group_details_preferences, s);
}
public static GroupDetailsPrefFragment newInstance() {
GroupDetailsPrefFragment fragment = new GroupDetailsPrefFragment();
return fragment;
}
}
GroupDetailsMembersFragment.java - Completely empty for now..
public class GroupDetailsMembersFragment extends Fragment {
public static final String TAG = "GroupDetailsMembersFragment";
public static GroupDetailsMembersFragment newInstance() {
GroupDetailsMembersFragment fragment = new GroupDetailsMembersFragment();
return fragment;
}
}
activity_group_details.xml - Activity's layout
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="match_parent"
android:layout_height="match_parent">
<FrameLayout
android:id="@+id/flPrefFragment"
android:layout_width="match_parent"
android:layout_height="wrap_content"/>
<FrameLayout
android:id="@+id/flMembersFragment"
android:layout_width="match_parent"
android:layout_height="wrap_content"/>
</LinearLayout>
group_details_preferences.xml - The preference XML file
<?xml version="1.0" encoding="utf-8"?>
<PreferenceScreen xmlns:android="http://schemas.android.com/apk/res/android">
<Preference
android:title="@string/remove_me"
android:key="@string/pref_key_settings_remove_me"/>
<Preference
android:title="@string/delete_group"
android:key="@string/pref_key_settings_delete_group"/>
</PreferenceScreen>
Trying to compile and run the code above lead me into a few errors, the first one was regarding a preference theme that was not set. I have quickly scanned the internet and found you need to add the following line into your Activity's theme : <item name="preferenceTheme">@style/PreferenceThemeOverlay.v14.Material</item>
To do so, I was needed to add the support-v14 library to gradle!
Trying to run the code again, lead me to another error, which is the reason I am posting this, and so far I didn't find any way to solve this issue. Here is the crash log :
java.lang.RuntimeException: Unable to start activity ComponentInfo{com.cochat.android/com.cochat.android.ui.groups.details.GroupDetailsActivity}: java.lang.RuntimeException: Content has view with id attribute 'android.R.id.list_container' that is not a ViewGroup class
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2305)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2363)
at android.app.ActivityThread.access$900(ActivityThread.java:161)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1265)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:157)
at android.app.ActivityThread.main(ActivityThread.java:5356)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:515)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1265)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1081)
at dalvik.system.NativeStart.main(Native Method)
Caused by: java.lang.RuntimeException: Content has view with id attribute 'android.R.id.list_container' that is not a ViewGroup class
at android.support.v7.preference.PreferenceFragmentCompat.onCreateView(PreferenceFragmentCompat.java:269)
at android.support.v4.app.Fragment.performCreateView(Fragment.java:2184)
at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:1298)
at android.support.v4.app.FragmentManagerImpl.moveFragmentsToInvisible(FragmentManager.java:2323)
at android.support.v4.app.FragmentManagerImpl.executeOpsTogether(FragmentManager.java:2136)
at android.support.v4.app.FragmentManagerImpl.optimizeAndExecuteOps(FragmentManager.java:2092)
at android.support.v4.app.FragmentManagerImpl.execPendingActions(FragmentManager.java:1998)
at android.support.v4.app.FragmentController.execPendingActions(FragmentController.java:388)
at android.support.v4.app.FragmentActivity.onStart(FragmentActivity.java:607)
at android.support.v7.app.AppCompatActivity.onStart(AppCompatActivity.java:181)
at android.app.Instrumentation.callActivityOnStart(Instrumentation.java:1189)
at android.app.Activity.performStart(Activity.java:5441)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2278)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2363)
at android.app.ActivityThread.access$900(ActivityThread.java:161)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1265)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:157)
at android.app.ActivityThread.main(ActivityThread.java:5356)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:515)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1265)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1081)
at dalvik.system.NativeStart.main(Native Method)
Been stuck on this for a while now, tried looking up different posts on stackoverflow or other websites, seen some solutions, but for some reason none of them managed to solve my problem.
Edit:
My gradle file contains the following:
compileSdkVersion 25
buildToolsVersion '25.0.2'
...
compile 'com.android.support:preference-v7:25.1.0'
compile 'com.android.support:preference-v14:25.1.0'
Update Jan 02 '17
I've been looking into the source code of PreferenceFragmentCompat and seen it is trying to load the following layout: R.layout.preference_list_fragment.
In the onCreateView() method of the class, it is inflating the layout, and trying to look for the id android.R.id.list_container.
The problem is that there is no such id within the layout.
Here is a code snippet from the PreferenceFragmentCompat:
final View view = themedInflater.inflate(mLayoutResId, container, false);
final View rawListContainer = view.findViewById(AndroidResources.ANDROID_R_LIST_CONTAINER);
if (!(rawListContainer instanceof ViewGroup)) {
throw new RuntimeException("Content has view with id attribute "
+ "'android.R.id.list_container' that is not a ViewGroup class");
}
While
private int mLayoutResId = R.layout.preference_list_fragment;
Still looking for a solution, thanks!
Answer
I got past this using the following bugfix: https://github.com/Gericop/Android-Support-Preference-V7-Fix
Simple 3 step process is to update the app's build.gradle,
Remove:
compile 'com.android.support:preference-v7:25.0.1'
compile 'com.android.support:preference-v14:25.0.1'
Add
compile 'com.takisoft.fix:preference-v7:25.0.1.0'
Then update your app's theme for preferences to use PreferenceFixTheme
(You're already using PreferenceFragmentCompat so good to go).
UPDATE:
On further investigation, with api 25.1.0, AppCompat worked fine once I realized the very strict restrictions on the style for Preferences.
I found this resource very helpful in getting everything set up nicely: