Convert to using the ObservableTreeMap and its adapter

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

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

@@ -67,6 +67,33 @@ public final class BindingAdapters {
         }
     }
 
+    @BindingAdapter({"items", "layout"})
+    public static <K extends Comparable<K>, V> void sortedMapBinding(final ListView view,
+                                         final ObservableSortedMap<K, V> oldMap,
+                                         final int oldLayoutId,
+                                         final ObservableSortedMap<K, V> newMap,
+                                         final int newLayoutId) {
+        // Remove any existing binding when there is no new map.
+        if (newMap == null) {
+            view.setAdapter(null);
+            return;
+        }
+        // The ListAdapter interface is not generic, so this cannot be checked.
+        @SuppressWarnings("unchecked")
+        ObservableMapAdapter<K, V> adapter = (ObservableMapAdapter<K, V>) view.getAdapter();
+        // If the layout changes, any existing adapter must be replaced.
+        if (newLayoutId != oldLayoutId)
+            adapter = null;
+        // Add a new binding if there was none, or if it must be replaced due to a layout change.
+        if (adapter == null) {
+            adapter = new ObservableMapAdapter<>(view.getContext(), newLayoutId, newMap);
+            view.setAdapter(adapter);
+        } else if (newMap != oldMap) {
+            // Changing the list only requires modifying the existing adapter.
+            adapter.setMap(newMap);
+        }
+    }
+
     @BindingAdapter({"android:textStyle"})
     public static void textStyleBinding(final TextView view, final Typeface typeface) {
         view.setTypeface(typeface);

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

@@ -78,7 +78,10 @@ public class ConfigListFragment extends BaseConfigFragment {
 
     private void setConfigChecked(final Config config) {
         if (config != null) {
-            final int position = VpnService.getInstance().getConfigs().indexOfKey(config.getName());
+            @SuppressWarnings("unchecked")
+            final ObservableMapAdapter<String, Config> adapter =
+                    (ObservableMapAdapter<String, Config>) listView.getAdapter();
+            final int position = adapter.getItemPosition(config.getName());
             if (position >= 0)
                 listView.setItemChecked(position, true);
         } else {

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

@@ -41,7 +41,7 @@ public class VpnService extends Service
     }
 
     private final IBinder binder = new Binder();
-    private final ObservableArrayMap<String, Config> configurations = new ObservableArrayMap<>();
+    private final ObservableTreeMap<String, Config> configurations = new ObservableTreeMap<>();
     private final Set<String> enabledConfigs = new HashSet<>();
     private SharedPreferences preferences;
     private Config primaryConfig;
@@ -103,7 +103,7 @@ public class VpnService extends Service
      *
      * @return The set of known configurations.
      */
-    public ObservableArrayMap<String, Config> getConfigs() {
+    public ObservableSortedMap<String, Config> getConfigs() {
         return configurations;
     }
 

app/src/main/res/layout/config_list_fragment.xml

@@ -7,7 +7,7 @@
         <!--suppress AndroidDomInspection -->
         <variable
             name="configs"
-            type="android.databinding.ObservableArrayMap&lt;String, com.wireguard.config.Config&gt;" />
+            type="com.wireguard.android.ObservableSortedMap&lt;String, com.wireguard.config.Config&gt;" />
     </data>
 
     <ListView