Develop Reference

Reverting an android preference's value when a statement in another thread fails

I have settings in my app that I allow the user to manipulate using a PreferenceScreen with Preferences. However, I want to store the settings on a server so that the settings can persist over multiple devices. I have the following code that lets me do this:
private void updateSettingOnPrefChange(final Preference pref, final Setting setting) {
pref.setOnPreferenceChangeListener(new Preference.OnPreferenceChangeListener() {
#Override
public boolean onPreferenceChange(Preference preference, final Object newValue) {
try {
setting.update(newValue, new Callback<Boolean>() {
#Override
public void call(Boolean succeeded) {
if (!succeeded) {
Toast.makeText(getActivity(), "Setting failed to update. Please try again.", Toast.LENGTH_LONG).show();
//here I need to revert the value of the Preference without again calling the onChangeListener
}
}
}, getActivity());
} catch (Exception ex) {
if (BuildConfig.DEBUG)
ex.printStackTrace();
Toast.makeText(getActivity(), "Setting failed to update. Please try again.", Toast.LENGTH_LONG).show();
return false;
}
return true;
}
});
}
As you can see in the code the request is being run on a different thread using a custom Callback class to clean up based on the result of the call. The issue is the code will have already return true on the main thread.
How can I revert the value of the Preference in the callback function (preferably without also calling the onPrefChangeListener function so I don't get infinite recursion)?

Use the OnPreferenceClickListener instead of OnPreferenceChangeListener to listen for user taps on the setting field and then make your rpc request accordingly. If you have to update the value (in the case of a server failure) you can change the setting without firing the click listener and having the infinite loop.
https://developer.android.com/reference/android/preference/Preference.html#setOnPreferenceClickListener(android.preference.Preference.OnPreferenceClickListener)

How to call an Android app's method remotely?

I'm working on a project that improves Automation Test for Android's App. What I want to do is very "easy": I have this very simple SIP Client with a basic UI and developed just reading the API guides on the android developer website (https://developer.android.com/guide/topics/connectivity/sip.html) that receives and makes SIP calls.
I need to control remotely this app from my PC, connected at the same local network or the same wifi, by sending commands or similar (without interact with the phone) to the app itslef running normally on my phone.For a specific example I posted the method initiateCall() that calls sipAddress(in the app, sipAddress is taken from a Text Box), what I want to do is:
Starting the app on my phone
calling the method initiateCall() from my pc giving a sipAddress as a parameter (I must not use the UI from the app running, that's why I need to give the sipAddress)
check if an outgoing call starts from the app running on my phone
I thought that the solution must be something about web-services,but I don't have any better ideas and i don't know how to start and where to start solving this problem,that's why i need you help.
public void initiateCall() {
try {
SipAudioCall.Listener listener = new SipAudioCall.Listener() {
// set up the listener for outgoing calls
#Override
public void onCallEstablished(SipAudioCall call) {
call.startAudio();
call.setSpeakerMode(true);
updateStatus(call, 2);
}
#Override
public void onCallEnded(SipAudioCall call) {
updateStatus("Call End");
}
};
call = manager.makeAudioCall(me.getUriString(), sipAddress,
listener, 30);
} catch (Exception e) {
Log.i("WalkieTalkieActivity/InitiateCall",
"Error when trying to close manager.", e);
if (me != null) {
try {
manager.close(me.getUriString());
} catch (Exception ee) {
Log.i("WalkieTalkieActivity/InitiateCall",
"Error when trying to close manager.", ee);
ee.printStackTrace();
}
}
if (call != null) {
call.close();
}
}
}

You could do it REST API style. You would need to set up a minimalistic webserver.
If you access for example the url phoneip/ctrl/makecall?number=yournumber a serverside method us called if set up correctly. Then you can call you method and use the GET or POST variables as arguments.
You would have to look into Java Webserver Libraries/Frameworks. You can pick a lightweight one for that purpose. For example this one.
You could then also add security features (authentification to protect it) quite easily.
Example with sparkjava
import static spark.Spark.*;
....
get("/ctrl/makecall", (request, response) -> {
String phonenum = request.queryParams("number"); //may not be accurate; you have to determine the GET variable called "number" in that case; you can rename it; see docs!!!
//call your method with proper arguments
});

RemotePlaybackClient, stop() not getting callback

I am attempting to write a RemotePlaybackClient sample app, in part because the one published by Google crashes aapt.
I can get RemotePlaybackClient to support play(), and it plays back a video on a Chromecast.
However, when I call stop(), to stop playback of the video, while the Chromecast does stop playback (showing a black screen with a cast icon centered), the SessionActionCallback that I pass into the stop() call does not get called with onResult():
private void stop() {
logToTranscript(getActivity().getString(R.string.stop_requested));
SessionActionCallback stopCB=new SessionActionCallback() {
#Override
public void onResult(Bundle data, String sessionId,
MediaSessionStatus sessionStatus) {
logToTranscript(getActivity().getString(R.string.stopped));
isPlaying=false;
isPaused=false;
getActivity().supportInvalidateOptionsMenu();
endSession();
}
};
client.stop(null, stopCB);
}
The same thing happens if I try pause() -- the SessionActionCallback passed to pause() is not invoked.
The sample code published by Google shows that these callbacks should be invoked, but, again, I can't get that to compile successfully.
Does anyone know under what circumstances the SessionActionCallback would not work, while the ItemActionCallback used with play() would work?
UPDATE
I have filed issue 66996 and issue 67032, the latter of which is specifically the problem I am seeing here, as I run into this same problem with the official sample app.

I beleive all Answer reside on how you make connection.
Because in google code ,code says that client which you had made shold not leave session and should not be null.
if (!mClient.hasSession()) {
// ignore if no session
return;
}
/*********Rest of the code would be unreachable***********/
#Override
public void pause() {
if (!mClient.hasSession()) {
// ignore if no session
return;
}
if (DEBUG) {
Log.d(TAG, "pause");
}
mClient.pause(null, new SessionActionCallback() {
#Override
public void onResult(Bundle data, String sessionId, MediaSessionStatus sessionStatus) {
logStatus("pause: succeeded", sessionId, sessionStatus, null, null);
if (mCallback != null) {
mCallback.onPlaylistChanged();
}
}
#Override
public void onError(String error, int code, Bundle data) {
logError("pause: failed", error, code);
}
});
}

How to join an active session running on a Chromcast device

I have to Users (User A and B) and one Chromecast device (C1).
User B starts a stream on C1.
User A connects to C1
Now User A should be able to control the stream running on C1. But every time I want to start a session the running stream on C1 is shut down and the receiver app is restarting.
Is there a way to join an active session? Or is that a job which has to be done by the web app running on the Chromecast device?
EDIT:
my sender app is a native Android app
Thanks!

You should have a look to the TicTacToe application. I think it does exactly that where 2 players can join the same game :
https://github.com/googlecast/cast-android-tictactoe
Hope this helps.
JN

What sort of sender are you using? Is it a native app (i.e. using Android or iOs SDK on a mobile device) or the sender is a chrome app?

On the receiver, you create a Receiver object and a ChannelHandler. You use the receiver to generate a ChannelFactory which you then pass to the ChannelHandler. The ChannelHandler now handles the creation of channels on the receiver. You will want to add an EventListener to the handler to listen to messages. Based on those messages you can do various things.
receiver = new cast.receiver.Receiver(YOUR_APP_ID, [YOUR_PROTOCOL], "", 5);
var dashHandler = new cast.receiver.ChannelHandler(YOUR_PROTOCOL);
dashHandler.addChannelFactory(receiver.createChannelFactory(YOUR_PROTOCOL));
dashHandler.addEventListener(cast.receiver.Channel.EventType.MESSAGE, onMessage.bind(this));
receiver.start();
...
onMessage = function (e) {
var message = e.message;
switch (message.type) {
...
}
}
On the sender, after a session is created you will want to send a check status message to the receiver to see if there are already channels attached. You can do this via your MessageStream and your receiver needs to respond in such a way that the MessageStream gets its status updated. You check that status to see if there are channels. If there are you can start listening to updates for your receiver. If not you can send a load event to the receiver to start your activity.
MediaProtocolCommand cmd = mMessageStream.requestStatus();
cmd.setListener(new MediaProtocolCommand.Listener() {
#Override
public void onCompleted(MediaProtocolCommand mPCommand) {
if (mMessageStream.getState() == 'channelsExist') {
//Start New Activity
} else {
//Join Existing Activity
}
#Override
public void onCancelled(MediaProtocolCommand mPCommand) {
}
});
This is kind of a vague response, but it could be more specific if I knew what you were trying to do. My app is using Google's RAMP protocol to play videos so my MessageStream and all it's messages are already defined. If you're doing something different, you need to create your own MessageStream.

Sorry for the late answer, but I figured it out by myself: It wasn't such complicated at all
I started the an Application like this
try {
mSession.startSession(applicationName,applicationArgs);
} catch (IllegalStateException e) {
Log.e(getClass().getSimpleName(), e.getMessage(), e);
} catch (IOException e) {
Log.e(getClass().getSimpleName(), e.getMessage(), e);
}
But it seems, that the MimeData applicationArgs is not needed at all. By removing the arguments and starting the session like below it works really fine!
try {
mSession.startSession(applicationName);
} catch (IllegalStateException e) {
Log.e(getClass().getSimpleName(), e.getMessage(), e);
} catch (IOException e) {
Log.e(getClass().getSimpleName(), e.getMessage(), e);
}
I hope this works for you too!

chromecast "failed to start application: no application is running" after called startSession()

I'm testing playing online video using chromecast.
After onRouteSelected(), I create the ApplicationSession and attach a MediaProtocalMessageStream;
Then I called mSession.startSession(); with no APP_ID, so I assume the build-in app inside chromecast play the video for me. This code works perfect and I can play online mp4 videos without writing my own receiver.
But, When I try to leave the video play app, I can't go back anymore, there is always an error message comes from onSessionStartFailed() which says
StartSessionTask failed with error: failed to start application: no
application is running
I don't remember how the first time I got into the video play app, which I don't leave for few day.
But I do know how I leave it, Here is what I did before I can never startSession again:
open Youtube app, get a deviced connected
play some youtube videos
disconnected from a chormecast, then the chromecast return to the starting page
So, doesn't anybody know what's going on here? How to open the build-in video app again?
By the way, My chromecast get a system update just after I return to the starting page, I don't know if google update something cause startSession() fail.
Below is the code I startSession and attach a mediaStream.
mSession = new ApplicationSession(mCastContext, mSelectedDevice);
ApplicationSession.Listener listener = new ApplicationSession.Listener() {
#Override
public void onSessionStarted(ApplicationMetadata appMetadata) {
mChannel = mSession.getChannel();
mStream = new MediaProtocolMessageStream();
mChannel.attachMessageStream(mStream);
if (mStream.getPlayerState() == null) {
ContentMetadata metaData = new ContentMetadata();
metaData.setTitle("Test Video");
String url = "http://www.auby.no/files/video_tests/h264_720p_hp_5.1_6mbps_ac3_planet.mp4";
try {
mCommand = mStream.loadMedia(url, metaData, true);
mCommand.setListener(new MediaProtocolCommand.Listener() {
#Override
public void onCompleted(MediaProtocolCommand arg0) {
onSetVolume(0.5);
}
#Override
public void onCancelled(MediaProtocolCommand arg0) {
}
});
} catch (IllegalStateException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
}
}
#Override
public void onSessionStartFailed(SessionError error) {
Log.d("TEST", "Session Started failed");
}
#Override
public void onSessionEnded(SessionError error) {
Log.d("TEST", "Session Started end");
}
};
mSession.setListener(listener);
try {
mSession.startSession();
} catch (IllegalStateException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}

You will have to use your own app id and own receiver. Google's default receiver doesn't play video streams anymore (it used to). It only handles Chrome tab mirroring now.