ProfileActivity: Refactor into clean layers of functionality

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

11 files changed, 281 insertions, 138 deletions

diff --git a/app/src/main/java/com/wireguard/android/PlaceholderFragment.java b/app/src/main/java/com/wireguard/android/PlaceholderFragment.java
deleted file mode 100644
index 8c15e757..00000000
--- a/app/src/main/java/com/wireguard/android/PlaceholderFragment.java
+++ /dev/null
@@ -1,18 +0,0 @@
-package com.wireguard.android;
-
-import android.app.Fragment;
-import android.os.Bundle;
-import android.view.LayoutInflater;
-import android.view.View;
-import android.view.ViewGroup;
-
-/**
- * Fragment containing a simple placeholder message.
- */
-
-public class PlaceholderFragment extends Fragment {
-    @Override
-    public View onCreateView(LayoutInflater inflater, ViewGroup parent, Bundle savedInstanceState) {
-        return inflater.inflate(R.layout.placeholder_fragment, parent, false);
-    }
-}
diff --git a/app/src/main/java/com/wireguard/android/ProfileActivity.java b/app/src/main/java/com/wireguard/android/ProfileActivity.java
index 040feb23..722f1dca 100644
--- a/app/src/main/java/com/wireguard/android/ProfileActivity.java
+++ b/app/src/main/java/com/wireguard/android/ProfileActivity.java
@@ -1,54 +1,53 @@
 package com.wireguard.android;
 
-import android.app.Activity;
+import android.app.Fragment;
+import android.app.FragmentManager;
 import android.app.FragmentTransaction;
-import android.content.ComponentName;
-import android.content.Context;
-import android.content.Intent;
-import android.content.ServiceConnection;
+import android.content.res.Configuration;
 import android.os.Bundle;
-import android.os.IBinder;
 import android.view.Menu;
 import android.view.MenuItem;
 
-import com.wireguard.config.Profile;
-
-import java.util.ArrayList;
-import java.util.List;
-
 /**
  * Activity that allows creating/viewing/editing/deleting WireGuard profiles.
  */
 
-public class ProfileActivity extends Activity {
-    private final ServiceConnection connection = new ProfileServiceConnection();
+public class ProfileActivity extends ServiceClientActivity<ProfileServiceInterface> {
+    public static final String KEY_PROFILE_NAME = "profile_name";
+
+    // FIXME: These must match the constants in profile_list_activity.xml
+    private static final String TAG_DETAIL = "detail";
+    private static final String TAG_LIST = "list";
+
+    private String currentProfile;
     private boolean isSplitLayout;
-    private final List<ServiceConnectionListener> listeners = new ArrayList<>();
-    private ProfileServiceInterface service;
 
-    public void addServiceConnectionListener(ServiceConnectionListener listener) {
-        listeners.add(listener);
+    public ProfileActivity() {
+        super(ProfileService.class);
     }
 
-    public ProfileServiceInterface getService() {
-        return service;
+    @Override
+    public void onBackPressed() {
+        if (!isSplitLayout && currentProfile != null) {
+            onProfileSelected(null);
+        } else {
+            super.onBackPressed();
+        }
     }
 
     @Override
     protected void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
-        // This layout consists only of containers for fragments.
+        // Restore the saved profile if there is one; otherwise grab it from the intent.
+        if (savedInstanceState != null)
+            currentProfile = savedInstanceState.getString(KEY_PROFILE_NAME);
+        else
+            currentProfile = getIntent().getStringExtra(KEY_PROFILE_NAME);
+        // Set up the base layout and fill it with fragments.
         setContentView(R.layout.profile_activity);
-        isSplitLayout = findViewById(R.id.detail_fragment_container) != null;
-        // Fill the layout with the initial set of fragments.
-        final FragmentTransaction transaction = getFragmentManager().beginTransaction();
-        transaction.add(R.id.list_fragment_container, new ProfileListFragment());
-        if (isSplitLayout)
-            transaction.add(R.id.detail_fragment_container, new PlaceholderFragment());
-        transaction.commit();
-        // Ensure the long-running service is started. This only needs to happen once.
-        final Intent intent = new Intent(this, ProfileService.class);
-        startService(intent);
+        final int orientation = getResources().getConfiguration().orientation;
+        isSplitLayout = orientation == Configuration.ORIENTATION_LANDSCAPE;
+        updateLayout(currentProfile);
     }
 
     @Override
@@ -57,50 +56,54 @@ public class ProfileActivity extends Activity {
         return true;
     }
 
-    public void onMenuSettings(MenuItem item) {
+    public void onMenuEdit(MenuItem item) {
 
     }
 
-    public void onProfileSelected(Profile profile) {
+    public void onMenuSave(MenuItem item) {
 
     }
 
-    @Override
-    public void onStart() {
-        super.onStart();
-        Intent intent = new Intent(this, ProfileService.class);
-        bindService(intent, connection, Context.BIND_AUTO_CREATE);
-    }
+    public void onMenuSettings(MenuItem item) {
 
-    @Override
-    public void onStop() {
-        super.onStop();
-        if (service != null) {
-            unbindService(connection);
-            for (ServiceConnectionListener listener : listeners)
-                listener.onServiceDisconnected();
-            service = null;
-        }
     }
 
-    public void removeServiceConnectionListener(ServiceConnectionListener listener) {
-        listeners.remove(listener);
+    public void onProfileSelected(String profile) {
+        updateLayout(profile);
+        currentProfile = profile;
     }
 
-    private class ProfileServiceConnection implements ServiceConnection {
-        @Override
-        public void onServiceConnected(ComponentName component, IBinder binder) {
-            service = (ProfileServiceInterface) binder;
-            for (ServiceConnectionListener listener : listeners)
-                listener.onServiceConnected(service);
-        }
+    @Override
+    public void onSaveInstanceState(Bundle outState) {
+        super.onSaveInstanceState(outState);
+        outState.putString(KEY_PROFILE_NAME, currentProfile);
+    }
 
-        @Override
-        public void onServiceDisconnected(ComponentName component) {
-            // This function is only called when the service crashes or goes away unexpectedly.
-            for (ServiceConnectionListener listener : listeners)
-                listener.onServiceDisconnected();
-            service = null;
+    private void updateLayout(String profile) {
+        final FragmentManager fm = getFragmentManager();
+        final Fragment detailFragment = fm.findFragmentByTag(TAG_DETAIL);
+        final Fragment listFragment = fm.findFragmentByTag(TAG_LIST);
+        final FragmentTransaction transaction = fm.beginTransaction();
+        if (profile != null) {
+            if (isSplitLayout) {
+                if (listFragment.isHidden())
+                    transaction.show(listFragment);
+            } else {
+                transaction.hide(listFragment);
+            }
+            if (detailFragment.isHidden())
+                transaction.show(detailFragment);
+        } else {
+            if (isSplitLayout) {
+                if (detailFragment.isHidden())
+                    transaction.show(detailFragment);
+            } else {
+                transaction.hide(detailFragment);
+            }
+            if (listFragment.isHidden())
+                transaction.show(listFragment);
         }
+        transaction.commit();
+        ((ProfileDetailFragment) detailFragment).setProfile(profile);
     }
 }
diff --git a/app/src/main/java/com/wireguard/android/ProfileActivityFragment.java b/app/src/main/java/com/wireguard/android/ProfileActivityFragment.java
deleted file mode 100644
index 9ec9f51d..00000000
--- a/app/src/main/java/com/wireguard/android/ProfileActivityFragment.java
+++ /dev/null
@@ -1,51 +0,0 @@
-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;
-    }
-
-    @Override
-    public void onDetach() {
-        super.onDetach();
-        activity = null;
-    }
-
-    @Override
-    public void onStart() {
-        super.onStart();
-        activity.addServiceConnectionListener(this);
-        // If the service is already connected, there will be no callback, so run the handler now.
-        final ProfileServiceInterface service = activity.getService();
-        if (service != null)
-            onServiceConnected(service);
-    }
-
-    @Override
-    public void onStop() {
-        super.onStop();
-        activity.removeServiceConnectionListener(this);
-    }
-
-    @Override
-    public void onServiceConnected(ProfileServiceInterface service) {
-        this.service = service;
-    }
-
-    @Override
-    public void onServiceDisconnected() {
-        service = null;
-    }
-}
diff --git a/app/src/main/java/com/wireguard/android/ProfileDetailFragment.java b/app/src/main/java/com/wireguard/android/ProfileDetailFragment.java
new file mode 100644
index 00000000..4af7fb25
--- /dev/null
+++ b/app/src/main/java/com/wireguard/android/ProfileDetailFragment.java
@@ -0,0 +1,56 @@
+package com.wireguard.android;
+
+import android.os.Bundle;
+import android.view.LayoutInflater;
+import android.view.Menu;
+import android.view.MenuInflater;
+import android.view.View;
+import android.view.ViewGroup;
+
+import com.wireguard.android.databinding.ProfileDetailFragmentBinding;
+
+/**
+ * Fragment for viewing and editing a WireGuard profile.
+ */
+
+public class ProfileDetailFragment extends ServiceClientFragment<ProfileServiceInterface> {
+    private ProfileDetailFragmentBinding binding;
+    private String name;
+
+    public ProfileDetailFragment() {
+        super();
+        setArguments(new Bundle());
+    }
+
+    @Override
+    public void onCreate(Bundle savedInstanceState) {
+        super.onCreate(savedInstanceState);
+        name = getArguments().getString(ProfileActivity.KEY_PROFILE_NAME);
+        setHasOptionsMenu(true);
+    }
+
+    @Override
+    public void onCreateOptionsMenu(Menu menu, MenuInflater inflater) {
+        inflater.inflate(R.menu.profile_detail, menu);
+    }
+
+    @Override
+    public View onCreateView(LayoutInflater inflater, ViewGroup parent, Bundle savedInstanceState) {
+        binding = ProfileDetailFragmentBinding.inflate(inflater, parent, false);
+        return binding.getRoot();
+    }
+
+    @Override
+    public void onServiceConnected(ProfileServiceInterface service) {
+        super.onServiceConnected(service);
+        binding.setProfile(service.getProfiles().get(name));
+    }
+
+    public void setProfile(String name) {
+        this.name = name;
+        getArguments().putString(ProfileActivity.KEY_PROFILE_NAME, name);
+        final ProfileServiceInterface service = getService();
+        if (binding != null && service != null)
+            binding.setProfile(service.getProfiles().get(name));
+    }
+}
diff --git a/app/src/main/java/com/wireguard/android/ProfileListFragment.java b/app/src/main/java/com/wireguard/android/ProfileListFragment.java
index be9b8d42..ed72b63b 100644
--- a/app/src/main/java/com/wireguard/android/ProfileListFragment.java
+++ b/app/src/main/java/com/wireguard/android/ProfileListFragment.java
@@ -11,10 +11,10 @@ import com.wireguard.android.databinding.ProfileListFragmentBinding;
 import com.wireguard.config.Profile;
 
 /**
- * Fragment containing the list of available WireGuard profiles. Must be part of a ProfileActivity.
+ * Fragment containing the list of available WireGuard profiles.
  */
 
-public class ProfileListFragment extends ProfileActivityFragment {
+public class ProfileListFragment extends ServiceClientFragment<ProfileServiceInterface> {
     private ProfileListFragmentBinding binding;
 
     @Override
@@ -25,7 +25,7 @@ public class ProfileListFragment extends ProfileActivityFragment {
             @Override
             public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
                 final Profile profile = (Profile) parent.getItemAtPosition(position);
-                ((ProfileActivity) getActivity()).onProfileSelected(profile);
+                ((ProfileActivity) getActivity()).onProfileSelected(profile.getName());
             }
         });
         listView.setOnItemLongClickListener(new AdapterView.OnItemLongClickListener() {
@@ -33,6 +33,7 @@ public class ProfileListFragment extends ProfileActivityFragment {
             public boolean onItemLongClick(AdapterView<?> parent, View view, int position,
                                            long id) {
                 final Profile profile = (Profile) parent.getItemAtPosition(position);
+                final ProfileServiceInterface service = getService();
                 if (profile == null || service == null)
                     return false;
                 if (profile.getIsConnected())
diff --git a/app/src/main/java/com/wireguard/android/ProfileService.java b/app/src/main/java/com/wireguard/android/ProfileService.java
index 96371d6c..1f40a0a1 100644
--- a/app/src/main/java/com/wireguard/android/ProfileService.java
+++ b/app/src/main/java/com/wireguard/android/ProfileService.java
@@ -38,6 +38,9 @@ public class ProfileService extends Service {
     @Override
     public void onCreate() {
         rootShell = new RootShell(this);
+        // Ensure the service sticks around after being unbound. This only needs to happen once.
+        final Intent intent = new Intent(this, ProfileService.class);
+        startService(intent);
         new ProfileLoader().execute(getFilesDir().listFiles(new FilenameFilter() {
             @Override
             public boolean accept(File dir, String name) {
diff --git a/app/src/main/java/com/wireguard/android/ProfileServiceInterface.java b/app/src/main/java/com/wireguard/android/ProfileServiceInterface.java
index 54b32595..65dc27a0 100644
--- a/app/src/main/java/com/wireguard/android/ProfileServiceInterface.java
+++ b/app/src/main/java/com/wireguard/android/ProfileServiceInterface.java
@@ -8,7 +8,7 @@ import com.wireguard.config.Profile;
  * Interface for the background connection service.
  */
 
-public interface ProfileServiceInterface {
+interface ProfileServiceInterface {
     /**
      * Attempt to set up and enable an interface for this profile. The profile's connection state
      * will be updated if connection is successful. If this profile is already connected, or it is
diff --git a/app/src/main/java/com/wireguard/android/ServiceClientActivity.java b/app/src/main/java/com/wireguard/android/ServiceClientActivity.java
new file mode 100644
index 00000000..263e012c
--- /dev/null
+++ b/app/src/main/java/com/wireguard/android/ServiceClientActivity.java
@@ -0,0 +1,75 @@
+package com.wireguard.android;
+
+import android.app.Activity;
+import android.content.ComponentName;
+import android.content.Context;
+import android.content.Intent;
+import android.content.ServiceConnection;
+import android.os.IBinder;
+
+import java.util.ArrayList;
+import java.util.List;
+
+/**
+ * Base class for activities that maintain a connection to a background service.
+ */
+
+abstract class ServiceClientActivity<T> extends Activity implements ServiceConnectionProvider<T> {
+    private final ServiceConnectionCallbacks callbacks = new ServiceConnectionCallbacks();
+    private final List<ServiceConnectionListener<T>> listeners = new ArrayList<>();
+    private T service;
+    private final Class<?> serviceClass;
+
+    protected ServiceClientActivity(Class<?> serviceClass) {
+        this.serviceClass = serviceClass;
+    }
+
+    @Override
+    public void addServiceConnectionListener(ServiceConnectionListener<T> listener) {
+        listeners.add(listener);
+    }
+
+    public T getService() {
+        return service;
+    }
+
+    @Override
+    public void onStart() {
+        super.onStart();
+        bindService(new Intent(this, serviceClass), callbacks, Context.BIND_AUTO_CREATE);
+    }
+
+    @Override
+    public void onStop() {
+        super.onStop();
+        if (service != null) {
+            service = null;
+            unbindService(callbacks);
+            for (ServiceConnectionListener listener : listeners)
+                listener.onServiceDisconnected();
+        }
+    }
+
+    @Override
+    public void removeServiceConnectionListener(ServiceConnectionListener<T> listener) {
+        listeners.remove(listener);
+    }
+
+    private class ServiceConnectionCallbacks implements ServiceConnection {
+        @Override
+        public void onServiceConnected(ComponentName component, IBinder binder) {
+            @SuppressWarnings("unchecked")
+            final T localBinder = (T) binder;
+            service = localBinder;
+            for (ServiceConnectionListener<T> listener : listeners)
+                listener.onServiceConnected(service);
+        }
+
+        @Override
+        public void onServiceDisconnected(ComponentName component) {
+            service = null;
+            for (ServiceConnectionListener<T> listener : listeners)
+                listener.onServiceDisconnected();
+        }
+    }
+}
diff --git a/app/src/main/java/com/wireguard/android/ServiceClientFragment.java b/app/src/main/java/com/wireguard/android/ServiceClientFragment.java
new file mode 100644
index 00000000..3b209438
--- /dev/null
+++ b/app/src/main/java/com/wireguard/android/ServiceClientFragment.java
@@ -0,0 +1,61 @@
+package com.wireguard.android;
+
+import android.app.Fragment;
+import android.content.Context;
+
+/**
+ * Base class for fragments in activities that maintain a connection to a background service.
+ */
+
+abstract class ServiceClientFragment<T> extends Fragment implements ServiceConnectionListener<T> {
+    private ServiceConnectionProvider<T> provider;
+    private T service;
+
+    protected T getService() {
+        return service;
+    }
+
+    @Override
+    public void onAttach(Context context) {
+        super.onAttach(context);
+        @SuppressWarnings("unchecked")
+        final ServiceConnectionProvider<T> localContext = (ServiceConnectionProvider<T>) context;
+        provider = localContext;
+    }
+
+    @Override
+    public void onDetach() {
+        super.onDetach();
+        provider = null;
+    }
+
+    @Override
+    public void onStart() {
+        super.onStart();
+        provider.addServiceConnectionListener(this);
+        // Run the handler if the connection state changed while we were not paying attention.
+        final T localService = provider.getService();
+        if (localService != service) {
+            if (localService != null)
+                onServiceConnected(localService);
+            else
+                onServiceDisconnected();
+        }
+    }
+
+    @Override
+    public void onStop() {
+        super.onStop();
+        provider.removeServiceConnectionListener(this);
+    }
+
+    @Override
+    public void onServiceConnected(T service) {
+        this.service = service;
+    }
+
+    @Override
+    public void onServiceDisconnected() {
+        service = null;
+    }
+}
diff --git a/app/src/main/java/com/wireguard/android/ServiceConnectionListener.java b/app/src/main/java/com/wireguard/android/ServiceConnectionListener.java
index 5f3c8d0a..c77fe931 100644
--- a/app/src/main/java/com/wireguard/android/ServiceConnectionListener.java
+++ b/app/src/main/java/com/wireguard/android/ServiceConnectionListener.java
@@ -1,11 +1,11 @@
 package com.wireguard.android;
 
 /**
- * Interface for fragments that need notification about connection changes to the ProfileService.
+ * Interface for fragments that need notification about service connection changes.
  */
 
-interface ServiceConnectionListener {
-    void onServiceConnected(ProfileServiceInterface service);
+interface ServiceConnectionListener<T> {
+    void onServiceConnected(T service);
 
     void onServiceDisconnected();
 }
diff --git a/app/src/main/java/com/wireguard/android/ServiceConnectionProvider.java b/app/src/main/java/com/wireguard/android/ServiceConnectionProvider.java
new file mode 100644
index 00000000..79a0efde
--- /dev/null
+++ b/app/src/main/java/com/wireguard/android/ServiceConnectionProvider.java
@@ -0,0 +1,13 @@
+package com.wireguard.android;
+
+/**
+ * Interface for activities that provide a connection to a service.
+ */
+
+interface ServiceConnectionProvider<T> {
+    void addServiceConnectionListener(ServiceConnectionListener<T> listener);
+
+    T getService();
+
+    void removeServiceConnectionListener(ServiceConnectionListener<T> listener);
+}