I've solved this without the CastCompanionLibrary, but based on google's CastHelloText-android sample. Basically what I did was:
- encode an image into a base64 string and send it as a message to a custom receiver
- modify the sample's receiver to receive a base64 string and set it as the image source.
- upload and register my receiver and have the application use the generated application id
This is the code for the receiver:
<!DOCTYPE html>
<html>
<head>
<style>
img#androidImage {
height:auto;
width:100%;
}
</style>
<title>Cast Hello Text</title>
</head>
<body>
<img id="androidImage" src="" />
<script type="text/javascript" src="//www.gstatic.com/cast/sdk/libs/receiver/2.0.0/cast_receiver.js"></script>
<script type="text/javascript">
window.onload = function() {
cast.receiver.logger.setLevelValue(0);
window.castReceiverManager = cast.receiver.CastReceiverManager.getInstance();
console.log('Starting Receiver Manager');
// handler for the 'ready' event
castReceiverManager.onReady = function(event) {
console.log('Received Ready event: ' + JSON.stringify(event.data));
window.castReceiverManager.setApplicationState("Application status is ready...");
};
// handler for 'senderconnected' event
castReceiverManager.onSenderConnected = function(event) {
console.log('Received Sender Connected event: ' + event.data);
console.log(window.castReceiverManager.getSender(event.data).userAgent);
};
// handler for 'senderdisconnected' event
castReceiverManager.onSenderDisconnected = function(event) {
console.log('Received Sender Disconnected event: ' + event.data);
if (window.castReceiverManager.getSenders().length == 0) {
window.close();
}
};
// handler for 'systemvolumechanged' event
castReceiverManager.onSystemVolumeChanged = function(event) {
console.log('Received System Volume Changed event: ' + event.data['level'] + ' ' +
event.data['muted']);
};
// create a CastMessageBus to handle messages for a custom namespace
window.messageBus =
window.castReceiverManager.getCastMessageBus(
'urn:x-cast:com.google.cast.sample.helloworld');
// handler for the CastMessageBus message event
window.messageBus.onMessage = function(event) {
console.log('Message recieved');
var obj = JSON.parse(event.data)
console.log('Message type: ' + obj.type);
if (obj.type == "text") {
console.log('Skipping message: ' + obj.data);
}
if (obj.type == "image") {
var source = 'data:image/png;base64,'.concat(obj.data)
displayImage(source);
}
// inform all senders on the CastMessageBus of the incoming message event
// sender message listener will be invoked
window.messageBus.send(event.senderId, event.data);
}
// initialize the CastReceiverManager with an application status message
window.castReceiverManager.start({statusText: "Application is starting"});
console.log('Receiver Manager started');
};
function displayImage(source) {
console.log('received image');
document.getElementById("androidImage").src=source;
window.castReceiverManager.setApplicationState('image source changed');
};
</script>
</body>
</html>
Below is the modified MainActivity.java code. Don't forget to modify the app_id in string.xml once your receiver application is registered.
2 notes:
- The sent messages are wrapped in a JSON object so I can filter out
the text messages.
- The ENCODED_IMAGE_STRING variable isn't defined in this
example, you'll have to find an image and convert it to a base64 string yourself.
MainActivity.java:
package com.example.casthelloworld;
import java.io.IOException;
import java.util.ArrayList;
import android.content.Intent;
import android.graphics.drawable.ColorDrawable;
import android.os.Bundle;
import android.speech.RecognizerIntent;
import android.support.v4.view.MenuItemCompat;
import android.support.v7.app.ActionBar;
import android.support.v7.app.ActionBarActivity;
import android.support.v7.app.MediaRouteActionProvider;
import android.support.v7.media.MediaRouteSelector;
import android.support.v7.media.MediaRouter;
import android.support.v7.media.MediaRouter.RouteInfo;
import android.util.Log;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.Toast;
import com.google.android.gms.cast.ApplicationMetadata;
import com.google.android.gms.cast.Cast;
import com.google.android.gms.cast.Cast.ApplicationConnectionResult;
import com.google.android.gms.cast.Cast.MessageReceivedCallback;
import com.google.android.gms.cast.CastDevice;
import com.google.android.gms.cast.CastMediaControlIntent;
import com.google.android.gms.common.ConnectionResult;
import com.google.android.gms.common.api.GoogleApiClient;
import com.google.android.gms.common.api.ResultCallback;
import com.google.android.gms.common.api.Status;
/**
* Main activity to send messages to the receiver.
*/
public class MainActivity extends ActionBarActivity {
private static final String TAG = MainActivity.class.getSimpleName();
private static final int REQUEST_CODE = 1;
private MediaRouter mMediaRouter;
private MediaRouteSelector mMediaRouteSelector;
private MediaRouter.Callback mMediaRouterCallback;
private CastDevice mSelectedDevice;
private GoogleApiClient mApiClient;
private Cast.Listener mCastListener;
private ConnectionCallbacks mConnectionCallbacks;
private ConnectionFailedListener mConnectionFailedListener;
private HelloWorldChannel mHelloWorldChannel;
private boolean mApplicationStarted;
private boolean mWaitingForReconnect;
private String mSessionId;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
ActionBar actionBar = getSupportActionBar();
actionBar.setBackgroundDrawable(new ColorDrawable(
android.R.color.transparent));
// When the user clicks on the button, use Android voice recognition to
// get text
Button voiceButton = (Button) findViewById(R.id.voiceButton);
voiceButton.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
startVoiceRecognitionActivity();
}
});
// When the user clicks on the button, use Android voice recognition to
// get text
Button yarrButton = (Button) findViewById(R.id.tmpButton);
yarrButton.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
castImage();
}
});
// Configure Cast device discovery
mMediaRouter = MediaRouter.getInstance(getApplicationContext());
mMediaRouteSelector = new MediaRouteSelector.Builder()
.addControlCategory(
CastMediaControlIntent.categoryForCast(getResources()
.getString(R.string.app_id))).build();
mMediaRouterCallback = new MyMediaRouterCallback();
}
private void castImage()
{
Log.d(TAG, "castImage()");
String image_string = createJsonMessage(MessageType.image, ENCODED_IMAGE_STRING);
sendMessage(image_string);
}
/**
* Android voice recognition
*/
private void startVoiceRecognitionActivity() {
Intent intent = new Intent(RecognizerIntent.ACTION_RECOGNIZE_SPEECH);
intent.putExtra(RecognizerIntent.EXTRA_LANGUAGE_MODEL,
RecognizerIntent.LANGUAGE_MODEL_FREE_FORM);
intent.putExtra(RecognizerIntent.EXTRA_PROMPT,
getString(R.string.message_to_cast));
startActivityForResult(intent, REQUEST_CODE);
}
/*
* Handle the voice recognition response
*
* @see android.support.v4.app.FragmentActivity#onActivityResult(int, int,
* android.content.Intent)
*/
@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
if (requestCode == REQUEST_CODE && resultCode == RESULT_OK) {
ArrayList<String> matches = data
.getStringArrayListExtra(RecognizerIntent.EXTRA_RESULTS);
if (matches.size() > 0) {
Log.d(TAG, matches.get(0));
String message = createJsonMessage(MessageType.text, matches.get(0));
sendMessage(message);
}
}
super.onActivityResult(requestCode, resultCode, data);
}
@Override
protected void onResume() {
super.onResume();
// Start media router discovery
mMediaRouter.addCallback(mMediaRouteSelector, mMediaRouterCallback,
MediaRouter.CALLBACK_FLAG_REQUEST_DISCOVERY);
}
@Override
protected void onPause() {
if (isFinishing()) {
// End media router discovery
mMediaRouter.removeCallback(mMediaRouterCallback);
}
super.onPause();
}
@Override
public void onDestroy() {
teardown();
super.onDestroy();
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
super.onCreateOptionsMenu(menu);
getMenuInflater().inflate(R.menu.main, menu);
MenuItem mediaRouteMenuItem = menu.findItem(R.id.media_route_menu_item);
MediaRouteActionProvider mediaRouteActionProvider = (MediaRouteActionProvider) MenuItemCompat
.getActionProvider(mediaRouteMenuItem);
// Set the MediaRouteActionProvider selector for device discovery.
mediaRouteActionProvider.setRouteSelector(mMediaRouteSelector);
return true;
}
/**
* Callback for MediaRouter events
*/
private class MyMediaRouterCallback extends MediaRouter.Callback {
@Override
public void onRouteSelected(MediaRouter router, RouteInfo info) {
Log.d(TAG, "onRouteSelected");
// Handle the user route selection.
mSelectedDevice = CastDevice.getFromBundle(info.getExtras());
launchReceiver();
}
@Override
public void onRouteUnselected(MediaRouter router, RouteInfo info) {
Log.d(TAG, "onRouteUnselected: info=" + info);
teardown();
mSelectedDevice = null;
}
}
/**
* Start the receiver app
*/
private void launchReceiver() {
try {
mCastListener = new Cast.Listener() {
@Override
public void onApplicationDisconnected(int errorCode) {
Log.d(TAG, "application has stopped");
teardown();
}
};
// Connect to Google Play services
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