ProfileList: Extract service management into a base class

It will be shared with other fragments.

Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>

app/src/main/java/com/wireguard/android/ProfileActivityFragment.java

@@ -0,0 +1,37 @@
+package com.wireguard.android;
+
+import android.app.Fragment;
+import android.content.Context;
+
+/**
+ * Base class for fragments that are part of a ProfileActivity.
+ */
+
+public class ProfileActivityFragment extends Fragment implements ServiceConnectionListener {
+    private ProfileActivity activity;
+    protected ProfileServiceInterface service;
+
+    @Override
+    public void onAttach(Context context) {
+        super.onAttach(context);
+        activity = (ProfileActivity) context;
+        activity.addServiceConnectionListener(this);
+        service = activity.getService();
+    }
+
+    @Override
+    public void onDetach() {
+        super.onDetach();
+        activity.removeServiceConnectionListener(this);
+    }
+
+    @Override
+    public void onServiceConnected(ProfileServiceInterface service) {
+        this.service = service;
+    }
+
+    @Override
+    public void onServiceDisconnected() {
+        service = null;
+    }
+}

app/src/main/java/com/wireguard/android/ProfileListFragment.java

@@ -1,7 +1,5 @@
 package com.wireguard.android;
 
-import android.app.Fragment;
-import android.content.Context;
 import android.os.Bundle;
 import android.view.LayoutInflater;
 import android.view.View;
@@ -16,18 +14,8 @@ import com.wireguard.config.Profile;
  * Fragment containing the list of available WireGuard profiles. Must be part of a ProfileActivity.
  */
 
-public class ProfileListFragment extends Fragment implements ServiceConnectionListener {
+public class ProfileListFragment extends ProfileActivityFragment {
-    private ProfileActivity activity;
     private ProfileListFragmentBinding binding;
-    private ProfileServiceInterface service;
-
-    @Override
-    public void onAttach(Context context) {
-        super.onAttach(context);
-        activity = (ProfileActivity) context;
-        activity.addServiceConnectionListener(this);
-        service = activity.getService();
-    }
 
     @Override
     public View onCreateView(LayoutInflater inflater, ViewGroup parent, Bundle savedInstanceState) {
@@ -57,20 +45,9 @@ public class ProfileListFragment extends Fragment implements ServiceConnectionLi
         return binding.getRoot();
     }
 
-    @Override
-    public void onDetach() {
-        super.onDetach();
-        activity.removeServiceConnectionListener(this);
-    }
-
     @Override
     public void onServiceConnected(ProfileServiceInterface service) {
-        this.service = service;
+        super.onServiceConnected(service);
         binding.setProfiles(service.getProfiles());
     }
-
-    @Override
-    public void onServiceDisconnected() {
-        service = null;
-    }
 }