[Pair hearing devices] Add "Saved devices" to show bonded but not connected hearing devices

* BaseHearingDevicePreferenceController will also be used in "Hearing devices", so extract to parent class first.

Bug: 237625815
Test: make RunSettingsRoboTests ROBOTEST_FILTER="(SavedHearingDeviceUpdaterTest|BaseBluetoothDevicePreferenceControllerTest|BluetoothDeviceUpdaterTest|AvailableMediaBluetoothDeviceUpdaterTest|ConnectedBluetoothDeviceUpdaterTest|SavedBluetoothDeviceUpdaterTest)"
Change-Id: I8a492866f48e3a664b9ff78bce5a4f082c0dc465

src/com/android/settings/accessibility/AccessibilityHearingAidsFragment.java

@@ -19,6 +19,7 @@ package com.android.settings.accessibility;
 import static android.os.UserManager.DISALLOW_CONFIG_BLUETOOTH;
 
 import android.content.ComponentName;
+import android.content.Context;
 import android.os.Bundle;
 import android.view.LayoutInflater;
 import android.view.View;
@@ -44,6 +45,12 @@ public class AccessibilityHearingAidsFragment extends AccessibilityShortcutPrefe
         super(DISALLOW_CONFIG_BLUETOOTH);
     }
 
+    @Override
+    public void onAttach(Context context) {
+        super.onAttach(context);
+        use(SavedHearingDevicePreferenceController.class).init(this);
+    }
+
     @Override
     public void onCreate(Bundle savedInstanceState) {
         mFeatureName = getContext().getString(R.string.accessibility_hearingaid_title);

src/com/android/settings/accessibility/BaseBluetoothDevicePreferenceController.java

@@ -0,0 +1,73 @@
+/*
+ * Copyright (C) 2023 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.settings.accessibility;
+
+import android.content.Context;
+import android.content.pm.PackageManager;
+
+import androidx.preference.Preference;
+import androidx.preference.PreferenceCategory;
+import androidx.preference.PreferenceScreen;
+
+import com.android.settings.connecteddevice.DevicePreferenceCallback;
+import com.android.settings.core.BasePreferenceController;
+
+/**
+ * Abstract base class for bluetooth preference controller to handle UI logic, e.g. availability
+ * status, preference added, and preference removed.
+ */
+public abstract class BaseBluetoothDevicePreferenceController extends BasePreferenceController
+        implements DevicePreferenceCallback {
+
+    private PreferenceCategory mPreferenceCategory;
+
+    public BaseBluetoothDevicePreferenceController(Context context,
+            String preferenceKey) {
+        super(context, preferenceKey);
+    }
+
+    @Override
+    public int getAvailabilityStatus() {
+        return (mContext.getPackageManager().hasSystemFeature(PackageManager.FEATURE_BLUETOOTH))
+                ? AVAILABLE
+                : CONDITIONALLY_UNAVAILABLE;
+    }
+
+    @Override
+    public void displayPreference(PreferenceScreen screen) {
+        super.displayPreference(screen);
+
+        mPreferenceCategory = screen.findPreference(getPreferenceKey());
+        mPreferenceCategory.setVisible(false);
+    }
+
+    @Override
+    public void onDeviceAdded(Preference preference) {
+        if (mPreferenceCategory.getPreferenceCount() == 0) {
+            mPreferenceCategory.setVisible(true);
+        }
+        mPreferenceCategory.addPreference(preference);
+    }
+
+    @Override
+    public void onDeviceRemoved(Preference preference) {
+        mPreferenceCategory.removePreference(preference);
+        if (mPreferenceCategory.getPreferenceCount() == 0) {
+            mPreferenceCategory.setVisible(false);
+        }
+    }
+}

src/com/android/settings/accessibility/SavedHearingDevicePreferenceController.java

@@ -0,0 +1,89 @@
+/*
+ * Copyright (C) 2023 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.settings.accessibility;
+
+import android.content.Context;
+
+import androidx.preference.Preference;
+import androidx.preference.PreferenceScreen;
+
+import com.android.settings.bluetooth.BluetoothDeviceUpdater;
+import com.android.settings.connecteddevice.DevicePreferenceCallback;
+import com.android.settings.dashboard.DashboardFragment;
+import com.android.settingslib.core.lifecycle.LifecycleObserver;
+import com.android.settingslib.core.lifecycle.events.OnResume;
+import com.android.settingslib.core.lifecycle.events.OnStart;
+import com.android.settingslib.core.lifecycle.events.OnStop;
+
+/**
+ * Controller to update the {@link androidx.preference.PreferenceCategory} for all
+ * saved ((bonded but not connected)) hearing devices, including ASHA and HAP profile.
+ * Parent class {@link BaseBluetoothDevicePreferenceController} will use
+ * {@link DevicePreferenceCallback} to add/remove {@link Preference}.
+ */
+public class SavedHearingDevicePreferenceController extends
+        BaseBluetoothDevicePreferenceController implements LifecycleObserver, OnStart, OnResume,
+        OnStop {
+
+    private BluetoothDeviceUpdater mSavedHearingDeviceUpdater;
+
+    public SavedHearingDevicePreferenceController(Context context,
+            String preferenceKey) {
+        super(context, preferenceKey);
+    }
+
+    /**
+     * Initializes objects in this controller. Need to call this before onStart().
+     *
+     * <p>Should not call this more than 1 time.
+     *
+     * @param fragment The {@link DashboardFragment} uses the controller.
+     */
+    public void init(DashboardFragment fragment) {
+        if (mSavedHearingDeviceUpdater != null) {
+            throw new IllegalStateException("Should not call init() more than 1 time.");
+        }
+        mSavedHearingDeviceUpdater = new SavedHearingDeviceUpdater(fragment.getContext(), this,
+                fragment.getMetricsCategory());
+    }
+
+    @Override
+    public void onStart() {
+        mSavedHearingDeviceUpdater.registerCallback();
+    }
+
+    @Override
+    public void onResume() {
+        mSavedHearingDeviceUpdater.refreshPreference();
+    }
+
+    @Override
+    public void onStop() {
+        mSavedHearingDeviceUpdater.unregisterCallback();
+    }
+
+    @Override
+    public void displayPreference(PreferenceScreen screen) {
+        super.displayPreference(screen);
+
+        if (isAvailable()) {
+            final Context context = screen.getContext();
+            mSavedHearingDeviceUpdater.setPrefContext(context);
+            mSavedHearingDeviceUpdater.forceUpdate();
+        }
+    }
+}

src/com/android/settings/accessibility/SavedHearingDeviceUpdater.java

@@ -0,0 +1,53 @@
+/*
+ * Copyright (C) 2023 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.settings.accessibility;
+
+import android.bluetooth.BluetoothDevice;
+import android.content.Context;
+
+import com.android.settings.bluetooth.SavedBluetoothDeviceUpdater;
+import com.android.settings.connecteddevice.DevicePreferenceCallback;
+import com.android.settingslib.bluetooth.CachedBluetoothDevice;
+
+/**
+ * Maintains and updates saved (bonded but not connected) hearing devices, including ASHA and HAP
+ * profile.
+ */
+public class SavedHearingDeviceUpdater extends SavedBluetoothDeviceUpdater {
+
+    private static final String PREF_KEY = "saved_hearing_device";
+
+    public SavedHearingDeviceUpdater(Context context,
+            DevicePreferenceCallback devicePreferenceCallback, int metricsCategory) {
+        super(context, devicePreferenceCallback, /* showConnectedDevice= */ false, metricsCategory);
+    }
+
+    @Override
+    public boolean isFilterMatched(CachedBluetoothDevice cachedDevice) {
+        final BluetoothDevice device = cachedDevice.getDevice();
+        final boolean isSavedHearingAidDevice = cachedDevice.isHearingAidDevice()
+                && device.getBondState() == BluetoothDevice.BOND_BONDED
+                && !device.isConnected();
+
+        return isSavedHearingAidDevice && isDeviceInCachedDevicesList(cachedDevice);
+    }
+
+    @Override
+    protected String getPreferenceKey() {
+        return PREF_KEY;
+    }
+}