From 5940e957a8c4a86e9e7b980785ce9de804c7a814 Mon Sep 17 00:00:00 2001
From: Philip Cohn-Cort <cliabhach@gmail.com>
Date: Mon, 13 Sep 2021 00:09:43 +0000
Subject: [PATCH] Display battery status at the bottom of each device on its
 `DeviceFragment`

kdeconnect-android!105
---
 res/layout/activity_device.xml                | 156 ++++++------------
 res/layout/list_item_with_icon_entry.xml      |  11 +-
 res/layout/view_pair_error.xml                |  37 +++++
 res/layout/view_pair_request.xml              |  77 +++++++++
 res/values/strings.xml                        |   7 +
 .../Plugins/BatteryPlugin/BatteryPlugin.java  |  37 ++++-
 .../BatteryPlugin/DeviceBatteryInfo.kt        |  30 ++++
 .../UserInterface/DeviceFragment.java         |  89 +++++++++-
 8 files changed, 326 insertions(+), 118 deletions(-)
 create mode 100644 res/layout/view_pair_error.xml
 create mode 100644 res/layout/view_pair_request.xml
 create mode 100644 src/org/kde/kdeconnect/Plugins/BatteryPlugin/DeviceBatteryInfo.kt

diff --git a/res/layout/activity_device.xml b/res/layout/activity_device.xml
index 9f2f4cb1..a0505c05 100644
--- a/res/layout/activity_device.xml
+++ b/res/layout/activity_device.xml
@@ -1,126 +1,68 @@
 <LinearLayout
     xmlns:android="http://schemas.android.com/apk/res/android"
     xmlns:tools="http://schemas.android.com/tools"
-    xmlns:app="http://schemas.android.com/apk/res-auto"
     android:layout_width="match_parent"
     android:layout_height="match_parent"
     android:orientation="vertical"
     tools:context="org.kde.kdeconnect.UserInterface.DeviceFragment">
 
-    <LinearLayout
-        android:id="@+id/pairing_buttons"
-        android:layout_width="match_parent"
-        android:layout_height="wrap_content"
-        android:layout_gravity="center"
-        android:orientation="vertical"
-        android:padding="@dimen/activity_vertical_margin"
-        android:visibility="gone">
-
-        <ProgressBar
-            android:id="@+id/pair_progress"
-            android:layout_width="fill_parent"
-            android:layout_height="wrap_content"
-            android:visibility="gone"/>
-
-        <TextView
-            android:id="@+id/pair_message"
-            android:layout_width="wrap_content"
-            android:layout_height="wrap_content"
-            android:layout_marginBottom="8dip"
-            android:text="@string/device_not_paired"
-            android:textAppearance="?android:attr/textAppearanceMedium"/>
-
-        <TextView
-            android:id="@+id/pair_verification"
-            android:layout_width="wrap_content"
-            android:layout_height="wrap_content"
-            android:drawablePadding="5dp"
-            android:drawableLeft="@drawable/ic_key"
-            android:drawableStart="@drawable/ic_key"
-            android:layout_marginBottom="8dip"
-            android:visibility="gone"
-            android:text=""
-            android:textAppearance="?android:attr/textAppearanceMedium"/>
-
-        <Button
-            android:id="@+id/pair_button"
-            android:layout_width="match_parent"
-            android:layout_height="wrap_content"
-            android:background="@drawable/button_round"
-            android:text="@string/request_pairing"
-            android:textColor="@android:color/white"/>
-
-
-        <LinearLayout
-            android:id="@+id/pair_request_buttons"
-            android:layout_width="match_parent"
-            android:layout_height="wrap_content"
-            android:layout_gravity="center"
-            android:visibility="gone">
-
-            <Button
-                android:id="@+id/accept_button"
-                android:layout_width="fill_parent"
-                android:layout_height="wrap_content"
-                android:layout_margin="4dip"
-                android:layout_weight="1"
-                android:background="@drawable/button_round"
-                android:text="@string/pairing_accept"
-                android:textColor="@android:color/white"/>
-
-            <Button
-                android:id="@+id/reject_button"
-                android:layout_width="fill_parent"
-                android:layout_height="wrap_content"
-                android:layout_margin="4dip"
-                android:layout_weight="1"
-                android:background="@drawable/button_round"
-                android:text="@string/pairing_reject"
-                android:textColor="@android:color/white"/>
-
-        </LinearLayout>
-    </LinearLayout>
-
-    <LinearLayout
-        android:id="@+id/error_message_container"
-        android:layout_width="match_parent"
-        android:layout_height="match_parent"
-        android:gravity="center"
-        android:orientation="horizontal"
-        android:padding="16dp"
-        android:visibility="gone">
-
-        <androidx.appcompat.widget.AppCompatImageView
-            android:id="@+id/error_message_icon"
-            android:layout_width="wrap_content"
-            android:layout_height="wrap_content"
-            android:importantForAccessibility="no"
-            android:paddingEnd="8dip"
-            android:paddingLeft="0dip"
-            android:paddingRight="8dip"
-            android:paddingStart="0dip"
-            android:src="@drawable/ic_error_outline_48dp"
-            app:tint="?attr/colorHighContrast"
-            tools:ignore="UnusedAttribute"/>
-
-        <TextView
-            android:id="@+id/not_reachable_message"
-            android:layout_width="match_parent"
-            android:layout_height="wrap_content"
-            android:gravity="center_vertical"
-            android:text="@string/unreachable_description"
-            android:textAppearance="?android:attr/textAppearanceMedium"
-            android:visibility="gone" />
-    </LinearLayout>
+    <!-- Layout shown when device is reachable but not yet paired -->
+    <include
+        android:id="@+id/pair_request"
+        layout="@layout/view_pair_request"
+        tools:visibility="gone"/>
 
+    <!-- Layout shown when we can't pair with device or device is not reachable -->
+    <include
+        android:id="@+id/pair_error"
+        layout="@layout/view_pair_error"
+        tools:visibility="gone"/>
 
+    <!-- Layout shown when device is paired and reachable -->
     <ListView
         android:id="@+id/buttons_list"
         android:layout_width="match_parent"
-        android:layout_height="match_parent"
+        android:layout_height="0dp"
         android:fillViewport="true"
         tools:context=".DeviceActivity"
         tools:listitem="@layout/list_item_with_icon_entry"
+        android:layout_weight=".8"
         android:divider="@null"
         android:dividerHeight="0dp" />
+
+    <!-- Extra information about the current device -->
+    <RelativeLayout
+        android:id="@+id/view_status_container"
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:elevation="4dp"
+        android:padding="8dp"
+        android:visibility="gone"
+        tools:visibility="visible"
+        tools:ignore="UnusedAttribute">
+
+        <TextView
+            android:id="@+id/view_status_title"
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            android:layout_alignParentTop="true"
+            android:padding="4dp"
+            android:text="@string/view_status_title"
+            android:textAppearance="@style/TextAppearance.MaterialComponents.Headline5"
+            />
+
+        <CheckedTextView
+            android:id="@+id/view_battery_status"
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            android:layout_below="@id/view_status_title"
+            android:checkMark="@null"
+            android:clickable="false"
+            android:padding="4dp"
+            android:textAppearance="@style/TextAppearance.MaterialComponents.Body1"
+            android:text="@string/battery_status_unknown"
+            tools:text="100%"
+            />
+
+    </RelativeLayout>
 </LinearLayout>
diff --git a/res/layout/list_item_with_icon_entry.xml b/res/layout/list_item_with_icon_entry.xml
index 88a9d928..5eaef42c 100644
--- a/res/layout/list_item_with_icon_entry.xml
+++ b/res/layout/list_item_with_icon_entry.xml
@@ -3,6 +3,7 @@
 <LinearLayout
     xmlns:android="http://schemas.android.com/apk/res/android"
     xmlns:app="http://schemas.android.com/apk/res-auto"
+    xmlns:tools="http://schemas.android.com/tools"
     android:layout_width="match_parent"
     android:layout_height="wrap_content"
     android:background="?android:attr/selectableItemBackground"
@@ -40,7 +41,9 @@
                 android:fadingEdge="horizontal"
                 android:singleLine="true"
                 android:text=""
-                android:textAppearance="?android:attr/textAppearanceMedium"/>
+                android:textAppearance="?android:attr/textAppearanceMedium"
+                tools:maxLength="20"
+                tools:text="@tools:sample/lorem/random"/>
 
             <TextView
                 android:id="@+id/list_item_entry_summary"
@@ -52,8 +55,10 @@
                 android:text=""
                 android:textAppearance="?android:attr/textAppearanceSmall"
                 android:textColor="#CC2222"
-                android:visibility="gone"/>
+                android:visibility="gone"
+                tools:text="Other (optional) info"
+                tools:visibility="visible"/>
 
         </LinearLayout>
 
-    </LinearLayout>
\ No newline at end of file
+</LinearLayout>
\ No newline at end of file
diff --git a/res/layout/view_pair_error.xml b/res/layout/view_pair_error.xml
new file mode 100644
index 00000000..ae8f603f
--- /dev/null
+++ b/res/layout/view_pair_error.xml
@@ -0,0 +1,37 @@
+<?xml version="1.0" encoding="utf-8"?>
+<LinearLayout
+    xmlns:app="http://schemas.android.com/apk/res-auto"
+    xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:tools="http://schemas.android.com/tools"
+    android:id="@+id/error_message_container"
+    android:layout_width="match_parent"
+    android:layout_height="match_parent"
+    android:gravity="center"
+    android:orientation="horizontal"
+    android:padding="16dp"
+    android:visibility="gone"
+    tools:visibility="visible">
+
+    <androidx.appcompat.widget.AppCompatImageView
+        android:id="@+id/error_message_icon"
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content"
+        android:importantForAccessibility="no"
+        android:paddingEnd="8dip"
+        android:paddingLeft="0dip"
+        android:paddingRight="8dip"
+        android:paddingStart="0dip"
+        android:src="@drawable/ic_error_outline_48dp"
+        app:tint="?attr/colorHighContrast"
+        tools:ignore="UnusedAttribute" />
+
+    <TextView
+        android:id="@+id/not_reachable_message"
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:gravity="center_vertical"
+        android:text="@string/unreachable_description"
+        android:textAppearance="?android:attr/textAppearanceMedium"
+        android:visibility="gone"
+        tools:visibility="visible" />
+</LinearLayout>
\ No newline at end of file
diff --git a/res/layout/view_pair_request.xml b/res/layout/view_pair_request.xml
new file mode 100644
index 00000000..46b1bf31
--- /dev/null
+++ b/res/layout/view_pair_request.xml
@@ -0,0 +1,77 @@
+<?xml version="1.0" encoding="utf-8"?>
+<LinearLayout
+    xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:tools="http://schemas.android.com/tools"
+    android:id="@+id/pairing_buttons"
+    android:layout_width="match_parent"
+    android:layout_height="wrap_content"
+    android:layout_gravity="center"
+    android:orientation="vertical"
+    android:padding="@dimen/activity_vertical_margin"
+    android:visibility="gone"
+    tools:visibility="visible">
+
+    <ProgressBar
+        android:id="@+id/pair_progress"
+        android:layout_width="fill_parent"
+        android:layout_height="wrap_content"
+        android:visibility="gone" />
+
+    <TextView
+        android:id="@+id/pair_message"
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content"
+        android:layout_marginBottom="8dip"
+        android:text="@string/device_not_paired"
+        android:textAppearance="?android:attr/textAppearanceMedium" />
+
+    <TextView
+        android:id="@+id/pair_verification"
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content"
+        android:drawablePadding="5dp"
+        android:drawableLeft="@drawable/ic_key"
+        android:drawableStart="@drawable/ic_key"
+        android:layout_marginBottom="8dip"
+        android:visibility="gone"
+        android:text=""
+        android:textAppearance="?android:attr/textAppearanceMedium" />
+
+    <Button
+        android:id="@+id/pair_button"
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:background="@drawable/button_round"
+        android:text="@string/request_pairing"
+        android:textColor="@android:color/white" />
+
+
+    <LinearLayout
+        android:id="@+id/pair_request_buttons"
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:layout_gravity="center"
+        android:visibility="gone">
+
+        <Button
+            android:id="@+id/accept_button"
+            android:layout_width="fill_parent"
+            android:layout_height="wrap_content"
+            android:layout_margin="4dip"
+            android:layout_weight="1"
+            android:background="@drawable/button_round"
+            android:text="@string/pairing_accept"
+            android:textColor="@android:color/white" />
+
+        <Button
+            android:id="@+id/reject_button"
+            android:layout_width="fill_parent"
+            android:layout_height="wrap_content"
+            android:layout_margin="4dip"
+            android:layout_weight="1"
+            android:background="@drawable/button_round"
+            android:text="@string/pairing_reject"
+            android:textColor="@android:color/white" />
+
+    </LinearLayout>
+</LinearLayout>
\ No newline at end of file
diff --git a/res/values/strings.xml b/res/values/strings.xml
index fac1dbb3..b1319352 100644
--- a/res/values/strings.xml
+++ b/res/values/strings.xml
@@ -135,6 +135,13 @@
     <string name="mouse_receiver_plugin_description">Receive remote mouse movement</string>
     <string name="mouse_receiver_plugin_name">Mouse receiver</string>
     <string name="mouse_receiver_no_permissions">You need to enable Accessibility Service</string>
+
+    <string name="view_status_title">Status</string>
+    <string name="battery_status_format">Battery: %d%%</string>
+    <string name="battery_status_low_format">Battery: %d%% Low Battery</string>
+    <string name="battery_status_charging_format">Battery: %d%% charging</string>
+    <string name="battery_status_unknown">Battery information not available</string>
+
     <string name="category_connected_devices">Connected devices</string>
     <string name="category_not_paired_devices">Available devices</string>
     <string name="category_remembered_devices">Remembered devices</string>
diff --git a/src/org/kde/kdeconnect/Plugins/BatteryPlugin/BatteryPlugin.java b/src/org/kde/kdeconnect/Plugins/BatteryPlugin/BatteryPlugin.java
index b6db8f04..2c6f6935 100644
--- a/src/org/kde/kdeconnect/Plugins/BatteryPlugin/BatteryPlugin.java
+++ b/src/org/kde/kdeconnect/Plugins/BatteryPlugin/BatteryPlugin.java
@@ -11,6 +11,8 @@ import android.content.Context;
 import android.content.Intent;
 import android.content.IntentFilter;
 import android.os.BatteryManager;
+import androidx.annotation.NonNull;
+import androidx.annotation.Nullable;
 
 import org.kde.kdeconnect.NetworkPacket;
 import org.kde.kdeconnect.Plugins.Plugin;
@@ -27,8 +29,15 @@ public class BatteryPlugin extends Plugin {
     private static final int THRESHOLD_EVENT_NONE = 0;
     private static final int THRESHOLD_EVENT_BATTERY_LOW = 1;
 
+    public static boolean isLowBattery(@NonNull DeviceBatteryInfo info) {
+        return info.getThresholdEvent() == THRESHOLD_EVENT_BATTERY_LOW;
+    }
+
     private final NetworkPacket batteryInfo = new NetworkPacket(PACKET_TYPE_BATTERY);
 
+    @Nullable
+    private DeviceBatteryInfo remoteBatteryInfo;
+
     @Override
     public String getDisplayName() {
         return context.getResources().getString(R.string.pref_plugin_battery);
@@ -73,6 +82,11 @@ public class BatteryPlugin extends Plugin {
         intentFilter.addAction(Intent.ACTION_BATTERY_LOW);
         Intent currentState = context.registerReceiver(receiver, intentFilter);
         receiver.onReceive(context, currentState);
+
+        // Request new battery info from the linked device
+        NetworkPacket np = new NetworkPacket(PACKET_TYPE_BATTERY_REQUEST);
+        np.set("request", true);
+        device.sendPacket(np);
         return true;
     }
 
@@ -89,17 +103,36 @@ public class BatteryPlugin extends Plugin {
             device.sendPacket(batteryInfo);
         }
 
+        if (PACKET_TYPE_BATTERY.equals(np.getType())) {
+            remoteBatteryInfo = new DeviceBatteryInfo(np);
+            device.onPluginsChanged();
+        }
+
         return true;
     }
 
+    /**
+     * The latest battery information about the linked device. Will be null if the linked device
+     * has not sent us any such information yet.
+     * <p>
+     * See {@link DeviceBatteryInfo} for info on which fields we expect to find.
+     * </p>
+     *
+     * @return the most recent packet received from the remote device. May be null
+     */
+    @Nullable
+    public DeviceBatteryInfo getRemoteBatteryInfo() {
+        return remoteBatteryInfo;
+    }
+
     @Override
     public String[] getSupportedPacketTypes() {
-        return new String[]{PACKET_TYPE_BATTERY_REQUEST};
+        return new String[]{PACKET_TYPE_BATTERY_REQUEST, PACKET_TYPE_BATTERY};
     }
 
     @Override
     public String[] getOutgoingPacketTypes() {
-        return new String[]{PACKET_TYPE_BATTERY};
+        return new String[]{PACKET_TYPE_BATTERY_REQUEST, PACKET_TYPE_BATTERY};
     }
 
 }
diff --git a/src/org/kde/kdeconnect/Plugins/BatteryPlugin/DeviceBatteryInfo.kt b/src/org/kde/kdeconnect/Plugins/BatteryPlugin/DeviceBatteryInfo.kt
new file mode 100644
index 00000000..4d59e99f
--- /dev/null
+++ b/src/org/kde/kdeconnect/Plugins/BatteryPlugin/DeviceBatteryInfo.kt
@@ -0,0 +1,30 @@
+package org.kde.kdeconnect.Plugins.BatteryPlugin
+
+import org.kde.kdeconnect.NetworkPacket
+
+/**
+ * Specialised data representation of the packets received by [BatteryPlugin].
+ *
+ * Constants for [thresholdEvent] may be found in [BatteryPlugin].
+ *
+ * @param currentCharge the amount of charge in the device's battery
+ * @param isCharging whether the device is charging
+ * @param thresholdEvent status classifier (used to indicate low battery, etc.)
+ * @see BatteryPlugin.isLowBattery
+ */
+data class DeviceBatteryInfo(
+        val currentCharge: Int,
+        val isCharging: Boolean,
+        val thresholdEvent: Int,
+) {
+
+    /**
+     * For use with packets of type [BatteryPlugin.PACKET_TYPE_BATTERY].
+     */
+    constructor(np: NetworkPacket) :
+            this(
+                    np.getInt("currentCharge"),
+                    np.getBoolean("isCharging"),
+                    np.getInt("thresholdEvent", 0)
+            )
+}
\ No newline at end of file
diff --git a/src/org/kde/kdeconnect/UserInterface/DeviceFragment.java b/src/org/kde/kdeconnect/UserInterface/DeviceFragment.java
index e28bf1e4..bbae3a35 100644
--- a/src/org/kde/kdeconnect/UserInterface/DeviceFragment.java
+++ b/src/org/kde/kdeconnect/UserInterface/DeviceFragment.java
@@ -19,6 +19,7 @@ import android.view.ViewGroup;
 
 import androidx.annotation.NonNull;
 import androidx.annotation.Nullable;
+import androidx.annotation.StringRes;
 import androidx.appcompat.app.AlertDialog;
 import androidx.fragment.app.DialogFragment;
 import androidx.fragment.app.Fragment;
@@ -29,6 +30,9 @@ import org.kde.kdeconnect.BackgroundService;
 import org.kde.kdeconnect.Device;
 import org.kde.kdeconnect.Helpers.SecurityHelpers.SslHelper;
 import org.kde.kdeconnect.Helpers.TelephonyHelper;
+import org.kde.kdeconnect.NetworkPacket;
+import org.kde.kdeconnect.Plugins.BatteryPlugin.BatteryPlugin;
+import org.kde.kdeconnect.Plugins.BatteryPlugin.DeviceBatteryInfo;
 import org.kde.kdeconnect.Plugins.Plugin;
 import org.kde.kdeconnect.Plugins.SMSPlugin.SMSPlugin;
 import org.kde.kdeconnect.UserInterface.List.FailedPluginListItem;
@@ -38,6 +42,8 @@ import org.kde.kdeconnect.UserInterface.List.PluginListHeaderItem;
 import org.kde.kdeconnect.UserInterface.List.SetDefaultAppPluginListItem;
 import org.kde.kdeconnect_tp.R;
 import org.kde.kdeconnect_tp.databinding.ActivityDeviceBinding;
+import org.kde.kdeconnect_tp.databinding.ViewPairErrorBinding;
+import org.kde.kdeconnect_tp.databinding.ViewPairRequestBinding;
 
 import java.util.ArrayList;
 import java.util.Collection;
@@ -63,7 +69,24 @@ public class DeviceFragment extends Fragment {
 
     private ArrayList<ListAdapter.Item> pluginListItems;
 
-    private ActivityDeviceBinding binding;
+    /**
+     * Top-level ViewBinding for this fragment.
+     *
+     * Host for {@link #pluginListItems}.
+     */
+    private ActivityDeviceBinding deviceBinding;
+    /**
+     * Not-yet-paired ViewBinding.
+     *
+     * Used to start and retry pairing.
+     */
+    private ViewPairRequestBinding binding;
+    /**
+     * Cannot-communicate ViewBinding.
+     *
+     * Used when the remote device is unreachable.
+     */
+    private ViewPairErrorBinding errorBinding;
 
     public DeviceFragment() {
     }
@@ -99,7 +122,12 @@ public class DeviceFragment extends Fragment {
     @Override
     public View onCreateView(@NonNull LayoutInflater inflater, ViewGroup container,
                              Bundle savedInstanceState) {
-        binding = ActivityDeviceBinding.inflate(inflater, container, false);
+        deviceBinding = ActivityDeviceBinding.inflate(inflater, container, false);
+
+        // Inner binding for the layout shown when we're not paired yet...
+        binding = deviceBinding.pairRequest;
+        // ...and for when pairing doesn't (or can't) work
+        errorBinding = deviceBinding.pairError;
 
         binding.pairButton.setOnClickListener(v -> {
             binding.pairButton.setVisibility(View.GONE);
@@ -148,7 +176,7 @@ public class DeviceFragment extends Fragment {
 
         });
 
-        return binding.getRoot();
+        return deviceBinding.getRoot();
     }
 
     String getDeviceId() { return mDeviceId; }
@@ -272,8 +300,9 @@ public class DeviceFragment extends Fragment {
                     boolean reachable = device.isReachable();
 
                     binding.pairingButtons.setVisibility(paired ? View.GONE : View.VISIBLE);
-                    binding.errorMessageContainer.setVisibility((paired && !reachable) ? View.VISIBLE : View.GONE);
-                    binding.notReachableMessage.setVisibility((paired && !reachable) ? View.VISIBLE : View.GONE);
+                    errorBinding.errorMessageContainer.setVisibility((paired && !reachable) ? View.VISIBLE : View.GONE);
+                    errorBinding.notReachableMessage.setVisibility((paired && !reachable) ? View.VISIBLE : View.GONE);
+                    deviceBinding.viewStatusContainer.setVisibility((paired && reachable) ? View.VISIBLE : View.GONE);
 
                     try {
                         pluginListItems = new ArrayList<>();
@@ -300,10 +329,12 @@ public class DeviceFragment extends Fragment {
                                     dialog.show(getChildFragmentManager(), null);
                                 }
                             });
+
+                            DeviceFragment.this.displayBatteryInfoIfPossible();
                         }
 
                         ListAdapter adapter = new ListAdapter(mActivity, pluginListItems);
-                        binding.buttonsList.setAdapter(adapter);
+                        deviceBinding.buttonsList.setAdapter(adapter);
 
                         mActivity.invalidateOptionsMenu();
 
@@ -373,4 +404,50 @@ public class DeviceFragment extends Fragment {
             pluginListItems.add(new FailedPluginListItem(plugin, action));
         }
     }
+
+    /**
+     * This method tries to display battery info for the remote device. Includes
+     * <ul>
+     *     <li>Current charge as a percentage</li>
+     *     <li>Whether the remote device is low on power</li>
+     *     <li>Whether the remote device is currently charging</li>
+     * </ul>
+     * <p>
+     *     This will show a simple message on the view instead if we don't have
+     *     accurate info right now.
+     * </p>
+     */
+    private void displayBatteryInfoIfPossible() {
+        boolean canDisplayBatteryInfo = false;
+        BatteryPlugin batteryPlugin = (BatteryPlugin) device.getLoadedPlugins().get(
+                Plugin.getPluginKey(BatteryPlugin.class)
+        );
+
+        if (batteryPlugin != null) {
+            DeviceBatteryInfo info = batteryPlugin.getRemoteBatteryInfo();
+            if (info != null) {
+                canDisplayBatteryInfo = true;
+
+                Context ctx = deviceBinding.viewBatteryStatus.getContext();
+
+                boolean isCharging = info.isCharging();
+                @StringRes
+                int resId;
+                if (isCharging) {
+                    resId = R.string.battery_status_charging_format;
+                } else if (BatteryPlugin.isLowBattery(info))  {
+                    resId = R.string.battery_status_low_format;
+                } else {
+                    resId = R.string.battery_status_format;
+                }
+
+                deviceBinding.viewBatteryStatus.setChecked(isCharging);
+                deviceBinding.viewBatteryStatus.setText(ctx.getString(resId, info.getCurrentCharge()));
+            }
+        }
+
+        if (!canDisplayBatteryInfo) {
+            deviceBinding.viewBatteryStatus.setText(R.string.battery_status_unknown);
+        }
+    }
 }