USI Stylus settings Fragment.

The USI stylus settings fragment shows specific preferences
for USI stylus devices only.

There is currently no way to access this fragment from the UI.

Bug: 251201006
DD: go/stylus-connected-devices-doc
Test: StylusUsiHeaderControllerTest
Change-Id: I18223abc8113dce977f57f930ba701da0a34cc18

res/xml/stylus_usi_details_fragment.xml

@@ -0,0 +1,33 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!--
+  ~ Copyright (C) 2022 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.
+  -->
+
+<PreferenceScreen
+    xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:settings="http://schemas.android.com/apk/res-auto"
+    android:title="@string/stylus_device_details_title">
+
+    <com.android.settingslib.widget.LayoutPreference
+        android:key="stylus_usi_header"
+        android:layout="@layout/settings_entity_header"
+        android:selectable="false"
+        settings:allowDividerBelow="true"
+        settings:searchable="false"/>
+
+    <PreferenceCategory
+        android:key="device_stylus"/>
+
+</PreferenceScreen>

src/com/android/settings/connecteddevice/stylus/StylusUsiDetailsFragment.java

@@ -0,0 +1,84 @@
+/*
+ * Copyright (C) 2022 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.connecteddevice.stylus;
+
+import android.app.settings.SettingsEnums;
+import android.content.Context;
+import android.hardware.input.InputManager;
+import android.view.InputDevice;
+
+import androidx.annotation.Nullable;
+import androidx.annotation.VisibleForTesting;
+
+import com.android.settings.R;
+import com.android.settings.dashboard.DashboardFragment;
+import com.android.settingslib.core.AbstractPreferenceController;
+import com.android.settingslib.core.lifecycle.Lifecycle;
+
+import java.util.ArrayList;
+import java.util.List;
+
+/** Controls the USI stylus details and provides updates to individual controllers. */
+public class StylusUsiDetailsFragment extends DashboardFragment {
+    private static final String TAG = StylusUsiDetailsFragment.class.getSimpleName();
+    private static final String KEY_DEVICE_INPUT_ID = "device_input_id";
+
+    @VisibleForTesting
+    @Nullable
+    InputDevice mInputDevice;
+
+    @Override
+    public void onAttach(Context context) {
+        super.onAttach(context);
+        int inputDeviceId = getArguments().getInt(KEY_DEVICE_INPUT_ID);
+        InputManager im = context.getSystemService(InputManager.class);
+        mInputDevice = im.getInputDevice(inputDeviceId);
+
+        super.onAttach(context);
+        if (mInputDevice == null) {
+            finish();
+        }
+    }
+
+
+    @Override
+    public int getMetricsCategory() {
+        // TODO(b/261988317): for new SettingsEnum for this page
+        return SettingsEnums.BLUETOOTH_DEVICE_DETAILS;
+    }
+
+    @Override
+    protected String getLogTag() {
+        return TAG;
+    }
+
+    @Override
+    protected int getPreferenceScreenResId() {
+        return R.xml.stylus_usi_details_fragment;
+    }
+
+    @Override
+    protected List<AbstractPreferenceController> createPreferenceControllers(Context context) {
+        ArrayList<AbstractPreferenceController> controllers = new ArrayList<>();
+        if (mInputDevice != null) {
+            Lifecycle lifecycle = getSettingsLifecycle();
+            controllers.add(new StylusUsiHeaderController(context, mInputDevice));
+            controllers.add(new StylusDevicesController(context, mInputDevice, lifecycle));
+        }
+        return controllers;
+    }
+}

src/com/android/settings/connecteddevice/stylus/StylusUsiHeaderController.java

@@ -0,0 +1,145 @@
+/*
+ * Copyright (C) 2022 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.connecteddevice.stylus;
+
+import android.content.Context;
+import android.hardware.BatteryState;
+import android.hardware.input.InputManager;
+import android.os.Bundle;
+import android.view.InputDevice;
+import android.view.View;
+import android.widget.ImageView;
+import android.widget.TextView;
+
+import androidx.annotation.NonNull;
+import androidx.preference.Preference;
+import androidx.preference.PreferenceScreen;
+
+import com.android.settings.R;
+import com.android.settings.core.BasePreferenceController;
+import com.android.settingslib.core.lifecycle.LifecycleObserver;
+import com.android.settingslib.core.lifecycle.events.OnCreate;
+import com.android.settingslib.core.lifecycle.events.OnDestroy;
+import com.android.settingslib.widget.LayoutPreference;
+
+import java.text.NumberFormat;
+
+/**
+ * This class adds a header for USI stylus devices with a heading, icon, and battery level.
+ * As opposed to the bluetooth device headers, this USI header gets its battery values
+ * from {@link InputManager} APIs, rather than the bluetooth battery levels.
+ */
+public class StylusUsiHeaderController extends BasePreferenceController implements
+        InputManager.InputDeviceBatteryListener, LifecycleObserver, OnCreate, OnDestroy {
+
+    private static final String KEY_STYLUS_USI_HEADER = "stylus_usi_header";
+    private static final String TAG = StylusUsiHeaderController.class.getSimpleName();
+
+    private final InputManager mInputManager;
+    private final InputDevice mInputDevice;
+
+    private LayoutPreference mHeaderPreference;
+
+
+    public StylusUsiHeaderController(Context context, InputDevice inputDevice) {
+        super(context, KEY_STYLUS_USI_HEADER);
+        mInputDevice = inputDevice;
+        mInputManager = context.getSystemService(InputManager.class);
+    }
+
+    @Override
+    public void displayPreference(PreferenceScreen screen) {
+        mHeaderPreference = screen.findPreference(getPreferenceKey());
+        View view = mHeaderPreference.findViewById(R.id.entity_header);
+        TextView titleView = view.findViewById(R.id.entity_header_title);
+        titleView.setText(R.string.stylus_usi_header_title);
+
+        ImageView iconView = mHeaderPreference.findViewById(R.id.entity_header_icon);
+        if (iconView != null) {
+            // TODO(b/250909304): get proper icon once VisD ready
+            iconView.setImageResource(R.drawable.circle);
+            iconView.setContentDescription("Icon for stylus");
+        }
+        refresh();
+        super.displayPreference(screen);
+    }
+
+    @Override
+    public void updateState(Preference preference) {
+        refresh();
+    }
+
+    private void refresh() {
+        BatteryState batteryState = mInputDevice.getBatteryState();
+        View view = mHeaderPreference.findViewById(R.id.entity_header);
+        TextView summaryView = view.findViewById(R.id.entity_header_summary);
+
+        if (isValidBatteryState(batteryState)) {
+            summaryView.setVisibility(View.VISIBLE);
+            summaryView.setText(
+                    NumberFormat.getPercentInstance().format(batteryState.getCapacity()));
+        } else {
+            summaryView.setVisibility(View.INVISIBLE);
+        }
+    }
+
+    /**
+     * This determines if a battery state is 'stale', as indicated by the presence of
+     * battery values.
+     *
+     * A USI battery state is valid (and present) if a USI battery value has been pulled
+     * within the last 1 hour of a stylus touching/hovering on the screen. The header shows
+     * battery values in this case, Conversely, a stale battery state means no USI battery
+     * value has been detected within the last 1 hour. Thus, the USI stylus preference will
+     * not be shown in Settings, and accordingly, the USI battery state won't surface.
+     *
+     * @param batteryState Latest battery state pulled from the kernel
+     */
+    private boolean isValidBatteryState(BatteryState batteryState) {
+        return batteryState != null
+                && batteryState.isPresent()
+                && batteryState.getCapacity() > 0f;
+    }
+
+    @Override
+    public int getAvailabilityStatus() {
+        return AVAILABLE;
+    }
+
+    @Override
+    public String getPreferenceKey() {
+        return KEY_STYLUS_USI_HEADER;
+    }
+
+    @Override
+    public void onBatteryStateChanged(int deviceId, long eventTimeMillis,
+            @NonNull BatteryState batteryState) {
+        refresh();
+    }
+
+    @Override
+    public void onCreate(Bundle savedInstanceState) {
+        mInputManager.addInputDeviceBatteryListener(mInputDevice.getId(),
+                mContext.getMainExecutor(), this);
+    }
+
+    @Override
+    public void onDestroy() {
+        mInputManager.removeInputDeviceBatteryListener(mInputDevice.getId(),
+                this);
+    }
+}

tests/robotests/src/com/android/settings/connecteddevice/stylus/StylusUsiHeaderControllerTest.java

@@ -0,0 +1,158 @@
+/*
+ * Copyright (C) 2022 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.connecteddevice.stylus;
+
+import static com.google.common.truth.Truth.assertThat;
+
+import static org.mockito.Mockito.spy;
+import static org.mockito.Mockito.verify;
+import static org.mockito.Mockito.when;
+
+import android.content.Context;
+import android.hardware.BatteryState;
+import android.hardware.input.InputManager;
+import android.os.Bundle;
+import android.view.InputDevice;
+import android.view.LayoutInflater;
+import android.view.View;
+import android.widget.TextView;
+
+import androidx.preference.PreferenceManager;
+import androidx.preference.PreferenceScreen;
+import androidx.test.core.app.ApplicationProvider;
+
+import com.android.settings.R;
+import com.android.settingslib.widget.LayoutPreference;
+
+import org.junit.Before;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.mockito.Mock;
+import org.mockito.MockitoAnnotations;
+import org.robolectric.RobolectricTestRunner;
+
+@RunWith(RobolectricTestRunner.class)
+public class StylusUsiHeaderControllerTest {
+
+    private Context mContext;
+    private StylusUsiHeaderController mController;
+    private LayoutPreference mLayoutPreference;
+    private PreferenceScreen mScreen;
+    private InputDevice mInputDevice;
+
+    @Mock
+    private InputManager mInputManager;
+    @Mock
+    private BatteryState mBatteryState;
+    @Mock
+    private Bundle mBundle;
+
+    @Before
+    public void setUp() {
+        MockitoAnnotations.initMocks(this);
+
+        InputDevice device = new InputDevice.Builder().setId(1).setSources(
+                InputDevice.SOURCE_BLUETOOTH_STYLUS).build();
+        mInputDevice = spy(device);
+        when(mInputDevice.getBatteryState()).thenReturn(mBatteryState);
+        when(mBatteryState.getCapacity()).thenReturn(1f);
+        when(mBatteryState.isPresent()).thenReturn(true);
+
+        mContext = spy(ApplicationProvider.getApplicationContext());
+        when(mContext.getSystemService(InputManager.class)).thenReturn(mInputManager);
+        mController = new StylusUsiHeaderController(mContext, mInputDevice);
+
+        PreferenceManager preferenceManager = new PreferenceManager(mContext);
+        mLayoutPreference = new LayoutPreference(mContext,
+                LayoutInflater.from(mContext).inflate(R.layout.advanced_bt_entity_header, null));
+        mLayoutPreference.setKey(mController.getPreferenceKey());
+
+        mScreen = preferenceManager.createPreferenceScreen(mContext);
+        mScreen.addPreference(mLayoutPreference);
+
+    }
+
+    @Test
+    public void onCreate_registersBatteryListener() {
+        mController.onCreate(mBundle);
+
+        verify(mInputManager).addInputDeviceBatteryListener(mInputDevice.getId(),
+                mContext.getMainExecutor(),
+                mController);
+    }
+
+    @Test
+    public void onDestroy_unregistersBatteryListener() {
+        mController.onDestroy();
+
+        verify(mInputManager).removeInputDeviceBatteryListener(mInputDevice.getId(),
+                mController);
+    }
+
+    @Test
+    public void displayPreference_showsCorrectTitle() {
+        mController.displayPreference(mScreen);
+
+        assertThat(((TextView) mLayoutPreference.findViewById(
+                R.id.entity_header_title)).getText().toString()).isEqualTo(
+                mContext.getString(R.string.stylus_usi_header_title));
+    }
+
+    @Test
+    public void displayPreference_hasBattery_showsCorrectBatterySummary() {
+        mController.displayPreference(mScreen);
+
+        assertThat(mLayoutPreference.findViewById(
+                R.id.entity_header_summary).getVisibility()).isEqualTo(View.VISIBLE);
+        assertThat(((TextView) mLayoutPreference.findViewById(
+                R.id.entity_header_summary)).getText().toString()).isEqualTo(
+                "100%");
+    }
+
+    @Test
+    public void displayPreference_noBattery_showsEmptySummary() {
+        when(mBatteryState.isPresent()).thenReturn(false);
+
+        mController.displayPreference(mScreen);
+
+        assertThat(mLayoutPreference.findViewById(
+                R.id.entity_header_summary).getVisibility()).isEqualTo(View.INVISIBLE);
+    }
+
+    @Test
+    public void displayPreference_invalidCapacity_showsEmptySummary() {
+        when(mBatteryState.getCapacity()).thenReturn(-1f);
+
+        mController.displayPreference(mScreen);
+
+        assertThat(mLayoutPreference.findViewById(
+                R.id.entity_header_summary).getVisibility()).isEqualTo(View.INVISIBLE);
+    }
+
+    @Test
+    public void onBatteryStateChanged_updatesSummary() {
+        mController.displayPreference(mScreen);
+
+        when(mBatteryState.getCapacity()).thenReturn(0.2f);
+        mController.onBatteryStateChanged(mInputDevice.getId(),
+                System.currentTimeMillis(), mBatteryState);
+
+        assertThat(((TextView) mLayoutPreference.findViewById(
+                R.id.entity_header_summary)).getText().toString()).isEqualTo(
+                "20%");
+    }
+}