Add new wifi display discovery API.

The API is quite simple.  There are a few extra functions
on DisplayManager to scan, connect and disconnect from
wifi displays and get status, and a single protected
broadcast sent when the status changes.

Change-Id: Ic91dbab5ee818e790b27fa32e1a1e93788793be0

Author: Jeff Brown

core/java/android/hardware/display/DisplayManager.java

@@ -40,6 +40,28 @@ public final class DisplayManager {
     private final Object mLock = new Object();
     private final SparseArray<Display> mDisplays = new SparseArray<Display>();
 
+    /**
+     * Broadcast receiver that indicates when the Wifi display status changes.
+     * <p>
+     * The status is provided as a {@link WifiDisplayStatus} object in the
+     * {@link #EXTRA_WIFI_DISPLAY_STATUS} extra.
+     * </p><p>
+     * This broadcast is only sent to registered receivers with the
+     * {@link android.Manifest.permission#CONFIGURE_WIFI_DISPLAY} permission and can
+     * only be sent by the system.
+     * </p>
+     * @hide
+     */
+    public static final String ACTION_WIFI_DISPLAY_STATUS_CHANGED =
+            "android.hardware.display.action.WIFI_DISPLAY_STATUS_CHANGED";
+
+    /**
+     * Contains a {@link WifiDisplayStatus} object.
+     * @hide
+     */
+    public static final String EXTRA_WIFI_DISPLAY_STATUS =
+            "android.hardware.display.extra.WIFI_DISPLAY_STATUS";
+
     /** @hide */
     public DisplayManager(Context context) {
         mContext = context;
@@ -126,6 +148,47 @@ public void unregisterDisplayListener(DisplayListener listener) {
         mGlobal.unregisterDisplayListener(listener);
     }
 
+    /**
+     * Initiates a fresh scan of availble Wifi displays.
+     * The results are sent as a {@link #ACTION_WIFI_DISPLAY_STATUS_CHANGED} broadcast.
+     * @hide
+     */
+    public void scanWifiDisplays() {
+        mGlobal.scanWifiDisplays();
+    }
+
+    /**
+     * Connects to a Wifi display.
+     * The results are sent as a {@link #ACTION_WIFI_DISPLAY_STATUS_CHANGED} broadcast.
+     *
+     * @param deviceAddress The MAC address of the device to which we should connect.
+     * @hide
+     */
+    public void connectWifiDisplay(String deviceAddress) {
+        mGlobal.connectWifiDisplay(deviceAddress);
+    }
+
+    /**
+     * Disconnects from the current Wifi display.
+     * The results are sent as a {@link #ACTION_WIFI_DISPLAY_STATUS_CHANGED} broadcast.
+     * @hide
+     */
+    public void disconnectWifiDisplay() {
+        mGlobal.disconnectWifiDisplay();
+    }
+
+    /**
+     * Gets the current Wifi display status.
+     * Watch for changes in the status by registering a broadcast receiver for
+     * {@link #ACTION_WIFI_DISPLAY_STATUS_CHANGED}.
+     *
+     * @return The current Wifi display status.
+     * @hide
+     */
+    public WifiDisplayStatus getWifiDisplayStatus() {
+        return mGlobal.getWifiDisplayStatus();
+    }
+
     /**
      * Listens for changes in available display devices.
      */

core/java/android/hardware/display/DisplayManagerGlobal.java

@@ -253,6 +253,43 @@ private void handleDisplayEvent(int displayId, int event) {
         }
     }
 
+    public void scanWifiDisplays() {
+        try {
+            mDm.scanWifiDisplays();
+        } catch (RemoteException ex) {
+            Log.e(TAG, "Failed to scan for Wifi displays.", ex);
+        }
+    }
+
+    public void connectWifiDisplay(String deviceAddress) {
+        if (deviceAddress == null) {
+            throw new IllegalArgumentException("deviceAddress must not be null");
+        }
+
+        try {
+            mDm.connectWifiDisplay(deviceAddress);
+        } catch (RemoteException ex) {
+            Log.e(TAG, "Failed to connect to Wifi display " + deviceAddress + ".", ex);
+        }
+    }
+
+    public void disconnectWifiDisplay() {
+        try {
+            mDm.disconnectWifiDisplay();
+        } catch (RemoteException ex) {
+            Log.e(TAG, "Failed to disconnect from Wifi display.", ex);
+        }
+    }
+
+    public WifiDisplayStatus getWifiDisplayStatus() {
+        try {
+            return mDm.getWifiDisplayStatus();
+        } catch (RemoteException ex) {
+            Log.e(TAG, "Failed to get Wifi display status.", ex);
+            return new WifiDisplayStatus();
+        }
+    }
+
     private final class DisplayManagerCallback extends IDisplayManagerCallback.Stub {
         @Override
         public void onDisplayEvent(int displayId, int event) {

core/java/android/hardware/display/IDisplayManager.aidl

@@ -17,6 +17,8 @@
 package android.hardware.display;
 
 import android.hardware.display.IDisplayManagerCallback;
+import android.hardware.display.WifiDisplay;
+import android.hardware.display.WifiDisplayStatus;
 import android.view.DisplayInfo;
 
 /** @hide */
@@ -25,4 +27,16 @@ interface IDisplayManager {
     int[] getDisplayIds();
 
     void registerCallback(in IDisplayManagerCallback callback);
+
+    // Requires CONFIGURE_WIFI_DISPLAY permission.
+    void scanWifiDisplays();
+
+    // Requires CONFIGURE_WIFI_DISPLAY permission.
+    void connectWifiDisplay(String address);
+
+    // Requires CONFIGURE_WIFI_DISPLAY permission.
+    void disconnectWifiDisplay();
+
+    // Requires CONFIGURE_WIFI_DISPLAY permission.
+    WifiDisplayStatus getWifiDisplayStatus();
 }

core/java/android/hardware/display/WifiDisplay.aidl

@@ -0,0 +1,19 @@
+/*
+ * Copyright (C) 2012 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 android.hardware.display;
+
+parcelable WifiDisplay;

core/java/android/hardware/display/WifiDisplay.java

@@ -0,0 +1,107 @@
+/*
+ * Copyright (C) 2012 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 android.hardware.display;
+
+import android.os.Parcel;
+import android.os.Parcelable;
+
+/**
+ * Describes the properties of a Wifi display.
+ * <p>
+ * This object is immutable.
+ * </p>
+ *
+ * @hide
+ */
+public final class WifiDisplay implements Parcelable {
+    private final String mDeviceAddress;
+    private final String mDeviceName;
+
+    public static final WifiDisplay[] EMPTY_ARRAY = new WifiDisplay[0];
+
+    public static final Creator<WifiDisplay> CREATOR = new Creator<WifiDisplay>() {
+        public WifiDisplay createFromParcel(Parcel in) {
+            String deviceAddress = in.readString();
+            String deviceName = in.readString();
+            return new WifiDisplay(deviceAddress, deviceName);
+        }
+
+        public WifiDisplay[] newArray(int size) {
+            return size == 0 ? EMPTY_ARRAY : new WifiDisplay[size];
+        }
+    };
+
+    public WifiDisplay(String deviceAddress, String deviceName) {
+        if (deviceAddress == null) {
+            throw new IllegalArgumentException("deviceAddress must not be null");
+        }
+        if (deviceName == null) {
+            throw new IllegalArgumentException("deviceName must not be null");
+        }
+
+        mDeviceAddress = deviceAddress;
+        mDeviceName = deviceName;
+    }
+
+    /**
+     * Gets the MAC address of the Wifi display device.
+     */
+    public String getDeviceAddress() {
+        return mDeviceAddress;
+    }
+
+    /**
+     * Gets the name of the Wifi display device.
+     */
+    public String getDeviceName() {
+        return mDeviceName;
+    }
+
+    @Override
+    public boolean equals(Object o) {
+        return o instanceof WifiDisplay && equals((WifiDisplay)o);
+    }
+
+    public boolean equals(WifiDisplay other) {
+        return other != null
+                && mDeviceAddress.equals(other.mDeviceAddress)
+                && mDeviceName.equals(other.mDeviceName);
+    }
+
+    @Override
+    public int hashCode() {
+        // The address on its own should be sufficiently unique for hashing purposes.
+        return mDeviceAddress.hashCode();
+    }
+
+    @Override
+    public void writeToParcel(Parcel dest, int flags) {
+        dest.writeString(mDeviceAddress);
+        dest.writeString(mDeviceName);
+    }
+
+    @Override
+    public int describeContents() {
+        return 0;
+    }
+
+    // For debugging purposes only.
+    @Override
+    public String toString() {
+        return mDeviceName + " (" + mDeviceAddress + ")";
+    }
+}

core/java/android/hardware/display/WifiDisplayStatus.aidl

@@ -0,0 +1,19 @@
+/*
+ * Copyright (C) 2012 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 android.hardware.display;
+
+parcelable WifiDisplayStatus;