Add ConnectedUsbDeviceUpdater

The usb updater listens to usb update and notify
ConnectedDeviceGroupController to add/remove
preference.

This cl:
1. Add ConntectedusbDeviceUpdater
2. Extract the UsbConnectionBroadcastReceiver since it would be
used both in controller and updater.
3. Add tests

Bug: 69333961
Test: RunSettingsRoboTests

Change-Id: Ic3b045a6faa4eba57d9b0c089ea1656141cc0220

src/com/android/settings/connecteddevice/ConnectedUsbDeviceUpdater.java

@@ -0,0 +1,92 @@
+/*
+ * Copyright (C) 2017 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;
+
+import android.content.Context;
+import android.content.Intent;
+import android.support.annotation.VisibleForTesting;
+
+import com.android.settings.R;
+import com.android.settings.deviceinfo.UsbBackend;
+import com.android.settings.deviceinfo.UsbModeChooserActivity;
+import com.android.settings.widget.GearPreference;
+
+/**
+ * Controller to maintain connected usb device
+ */
+public class ConnectedUsbDeviceUpdater {
+    private Context mContext;
+    private UsbBackend mUsbBackend;
+    private DevicePreferenceCallback mDevicePreferenceCallback;
+    @VisibleForTesting
+    GearPreference mUsbPreference;
+    @VisibleForTesting
+    UsbConnectionBroadcastReceiver mUsbReceiver;
+
+    private UsbConnectionBroadcastReceiver.UsbConnectionListener mUsbConnectionListener =
+            (connected) -> {
+                if (connected) {
+                    mUsbPreference.setSummary(
+                            UsbModePreferenceController.getSummary(mUsbBackend.getCurrentMode()));
+                    mDevicePreferenceCallback.onDeviceAdded(mUsbPreference);
+                } else {
+                    mDevicePreferenceCallback.onDeviceRemoved(mUsbPreference);
+                }
+            };
+
+    public ConnectedUsbDeviceUpdater(Context context,
+            DevicePreferenceCallback devicePreferenceCallback) {
+        this(context, devicePreferenceCallback, new UsbBackend(context));
+    }
+
+    @VisibleForTesting
+    ConnectedUsbDeviceUpdater(Context context, DevicePreferenceCallback devicePreferenceCallback,
+            UsbBackend usbBackend) {
+        mContext = context;
+        mDevicePreferenceCallback = devicePreferenceCallback;
+        mUsbBackend = usbBackend;
+        mUsbReceiver = new UsbConnectionBroadcastReceiver(context, mUsbConnectionListener);
+    }
+
+    public void registerCallback() {
+        // This method could handle multiple register
+        mUsbReceiver.register();
+    }
+
+    public void unregisterCallback() {
+        mUsbReceiver.unregister();
+    }
+
+    public void initUsbPreference(Context context) {
+        mUsbPreference = new GearPreference(context, null /* AttributeSet */);
+        mUsbPreference.setTitle(R.string.usb_pref);
+        mUsbPreference.setIcon(R.drawable.ic_usb);
+        mUsbPreference.setSelectable(false);
+        mUsbPreference.setOnGearClickListener((GearPreference p) -> {
+            final Intent intent = new Intent(mContext, UsbModeChooserActivity.class);
+            mContext.startActivity(intent);
+        });
+
+        forceUpdate();
+    }
+
+    private void forceUpdate() {
+        // Register so we can get the connection state from sticky intent.
+        //TODO(b/70336520): Use an API to get data instead of sticky intent
+        mUsbReceiver.register();
+        mUsbConnectionListener.onUsbConnectionChanged(mUsbReceiver.isConnected());
+    }
+}