Add Mic Toggle button to AppRTCDemo (Android).

BUG=webrtc:5671

Review URL: https://codereview.webrtc.org/1820113003

Cr-Commit-Position: refs/heads/master@{#12100}

webrtc/examples/androidapp/res/layout/fragment_call.xml

@@ -47,6 +47,14 @@
            android:contentDescription="@string/disconnect_call"
            android:layout_width="48dp"
            android:layout_height="48dp"/>
+
+       <ImageButton
+           android:id="@+id/button_call_toggle_mic"
+           android:background="@android:drawable/ic_btn_speak_now"
+           android:contentDescription="@string/toggle_mic"
+           android:layout_marginEnd="8dp"
+           android:layout_width="48dp"
+           android:layout_height="48dp"/>
     </LinearLayout>
 
     <TextView

webrtc/examples/androidapp/res/values/strings.xml

@@ -18,6 +18,7 @@
     <string name="ok">OK</string>
     <string name="switch_camera">Switch front/back camera</string>
     <string name="toggle_debug">Toggle debug view</string>
+    <string name="toggle_mic">Toggle microphone on/off</string>
     <string name="action_settings">Settings</string>
     <string name="add_room_description">Add new room to the list</string>
     <string name="remove_room_description">Remove room from the list</string>

webrtc/examples/androidapp/src/org/appspot/apprtc/CallActivity.java

@@ -132,6 +132,7 @@ public class CallActivity extends Activity
   private boolean isError;
   private boolean callControlFragmentVisible = true;
   private long callStartedTimeMs = 0;
+  private boolean micEnabled = true;
 
   // Controls
   private CallFragment callFragment;
@@ -337,6 +338,15 @@ public class CallActivity extends Activity
     }
   }
 
+  @Override
+  public boolean onToggleMic() {
+    if (peerConnectionClient != null) {
+      micEnabled = !micEnabled;
+      peerConnectionClient.setAudioEnabled(micEnabled);
+    }
+    return micEnabled;
+  }
+
   // Helper functions.
   private void toggleCallControlFragmentVisibility() {
     if (!iceConnected || !callFragment.isAdded()) {

webrtc/examples/androidapp/src/org/appspot/apprtc/CallFragment.java

@@ -31,6 +31,7 @@ public class CallFragment extends Fragment {
   private ImageButton disconnectButton;
   private ImageButton cameraSwitchButton;
   private ImageButton videoScalingButton;
+  private ImageButton toggleMuteButton;
   private TextView captureFormatText;
   private SeekBar captureFormatSlider;
   private OnCallEvents callEvents;
@@ -45,6 +46,7 @@ public class CallFragment extends Fragment {
     public void onCameraSwitch();
     public void onVideoScalingSwitch(ScalingType scalingType);
     public void onCaptureFormatChange(int width, int height, int framerate);
+    public boolean onToggleMic();
   }
 
   @Override
@@ -62,6 +64,8 @@ public class CallFragment extends Fragment {
         (ImageButton) controlView.findViewById(R.id.button_call_switch_camera);
     videoScalingButton =
         (ImageButton) controlView.findViewById(R.id.button_call_scaling_mode);
+    toggleMuteButton =
+        (ImageButton) controlView.findViewById(R.id.button_call_toggle_mic);
     captureFormatText =
         (TextView) controlView.findViewById(R.id.capture_format_text_call);
     captureFormatSlider =
@@ -99,6 +103,14 @@ public class CallFragment extends Fragment {
     });
     scalingType = ScalingType.SCALE_ASPECT_FILL;
 
+    toggleMuteButton.setOnClickListener(new View.OnClickListener() {
+      @Override
+      public void onClick(View view) {
+        boolean enabled = callEvents.onToggleMic();
+        toggleMuteButton.setAlpha(enabled ? 1.0f : 0.3f);
+      }
+    });
+
     return controlView;
   }
 

webrtc/examples/androidapp/src/org/appspot/apprtc/PeerConnectionClient.java

@@ -17,6 +17,7 @@ import android.util.Log;
 
 import org.appspot.apprtc.AppRTCClient.SignalingParameters;
 import org.appspot.apprtc.util.LooperExecutor;
+import org.webrtc.AudioTrack;
 import org.webrtc.CameraEnumerationAndroid;
 import org.webrtc.DataChannel;
 import org.webrtc.EglBase;
@@ -124,6 +125,9 @@ public class PeerConnectionClient {
   private boolean renderVideo;
   private VideoTrack localVideoTrack;
   private VideoTrack remoteVideoTrack;
+  // enableAudio is set to true if audio should be sent.
+  private boolean enableAudio;
+  private AudioTrack localAudioTrack;
 
   /**
    * Peer connection parameters.
@@ -252,6 +256,8 @@ public class PeerConnectionClient {
     renderVideo = true;
     localVideoTrack = null;
     remoteVideoTrack = null;
+    enableAudio = true;
+    localAudioTrack = null;
     statsTimer = new Timer();
 
     executor.execute(new Runnable() {
@@ -492,9 +498,7 @@ public class PeerConnectionClient {
       mediaStream.addTrack(createVideoTrack(videoCapturer));
     }
 
-    mediaStream.addTrack(factory.createAudioTrack(
-        AUDIO_TRACK_ID,
-        factory.createAudioSource(audioConstraints)));
+    mediaStream.addTrack(createAudioTrack());
     peerConnection.addStream(mediaStream);
 
     if (peerConnectionParameters.aecDump) {
@@ -605,6 +609,18 @@ public class PeerConnectionClient {
     }
   }
 
+  public void setAudioEnabled(final boolean enable) {
+    executor.execute(new Runnable() {
+      @Override
+      public void run() {
+        enableAudio = enable;
+        if (localAudioTrack != null) {
+          localAudioTrack.setEnabled(enableAudio);
+        }
+      }
+    });
+  }
+
   public void setVideoEnabled(final boolean enable) {
     executor.execute(new Runnable() {
       @Override
@@ -749,6 +765,14 @@ public class PeerConnectionClient {
     });
   }
 
+  private AudioTrack createAudioTrack() {
+    localAudioTrack = factory.createAudioTrack(
+        AUDIO_TRACK_ID,
+        factory.createAudioSource(audioConstraints));
+    localAudioTrack.setEnabled(enableAudio);
+    return localAudioTrack;
+  }
+
   private VideoTrack createVideoTrack(VideoCapturerAndroid capturer) {
     videoSource = factory.createVideoSource(capturer, videoConstraints);