app sent transaction to the server, user closes app, now a message needs to be
sent back to the phone from the server 10+ minutes later. The phone may be asleep, or the user might be checking his email. The question which I have is:
how can the phone be notified that a message has been received from server ?
how to display that message ?
A possible solution would be Google cloud messaging, but I still am not able to answer these 2 questions
1) You have to use SERVICE for that.
2) And to show that message.
Do like this.
The variable and method are members of Service class:
public final static String ACTION = "com.apps.example.MainActivity";
private void messageFromServer()//this method sends broadcast messages
{
Intent intent = new Intent(MOVEMENT_UPDATE);
String messageFromServer=serverMessage //here you will put server message
intent.putExtra("MessageFromServer", messageFromServer);
sendBroadcast(intent);
}
And this are the methods from Main activity:
You have to register receiver in the onResume method:
#Override
public void onResume()
{
IntentFilter intentFilter;
intentFilter= new IntentFilter(YourService.ACTION);
messageFromServer= new MessageFromServer();
registerReceiver(messageFromServer, intentFilter);
startYourService();
super.onResume();
}
private void startYourService()
{
startService(new Intent(this, YourService.class));
}
public class MessageFromServer extends BroadcastReceiver
{
#Override
public void onReceive(Context context, Intent intent)
{
// this method receives broadcast messages.
// Be sure to modify AndroidManifest.xml file in
// order to enable message receiving
String messageFromServer = intent.getStringExtra("MessageFromServer");
updateGUI();// here you can update the ui
}
}
and put service in you manifest file.
<service android:name="com.apps.service.YourService" ></service>
Related
I'm dealing with wearable, and my purpose is the next:
From my watch, I want to press a simple button, which send a simple message to the mobile. But I would like to handle all those behaviors :
when mobile app isn't yet launched, then launch the app and pass the message from wear, which can be handled in the launcher activity
when mobile app is launched but in the background, then just bring it to foreground and handle message from wear, which can be handled in the launcher activity
when mobile app is launched and in foreground, juste handle the message in the launcher activity
So far, I handle to launch the app when it isn't not yet launched, but I can't get the extra message in the launcher activity contained in the intent. Here the code.
the mobile service
public class MobileWearService extends WearableListenerService {
private static final String START_ACTIVITY = "/start_activity";
#Override
public void onMessageReceived(MessageEvent messageEvent) {
super.onMessageReceived(messageEvent);
String event = messageEvent.getPath();
String msg = new String(messageEvent.getData());
if (event.equals(START_ACTIVITY)) {
Intent intent = new Intent( this, MainActivity.class );
intent.putExtra("Data", msg);
intent.setFlags( Intent.FLAG_ACTIVITY_NEW_TASK
| Intent.FLAG_ACTIVITY_CLEAR_TOP
| Intent.FLAG_ACTIVITY_SINGLE_TOP);
startActivity( intent );
}
}
}
However, if I use a broadcast to send the message from service to the main activity, it works only if the app is launched and foreground
public class MobileWearService extends WearableListenerService {
private static final String START_ACTIVITY = "/start_activity";
#Override
public void onMessageReceived(MessageEvent messageEvent) {
super.onMessageReceived(messageEvent);
String event = messageEvent.getPath();
String msg = new String(messageEvent.getData());
if (event.equals(START_ACTIVITY)) {
broadcastIntent.setAction("com.me.project.wear.to.app");
broadcastIntent.putExtra("Data", msg);
broadcastIntent.putExtras(intent);
sendBroadcast(broadcastIntent);
}
}
}
launcher activity
private IntentFilter mIntentFilter = new IntentFilter("com.me.project.wear.to.app");
private BroadcastReceiver mReceiver = new BroadcastReceiver() {
#Override
public void onReceive(Context context, Intent intent) {
if (intent != null && intent.getAction().equals("com.me.project.wear.to.app")) {
String msg = intent.getStringExtra("Data");
}
}
};
#Override
protected void onResume() {
super.onResume();
registerReceiver(mReceiver, mIntentFilter);
}
#Override
protected void onPause() {
super.onPause();
unregisterReceiver(mReceiver);
}
So I would to combine the fact to get the message from wear (I know how to) but pass this message to get it in the launcher activity regardless of the state of the app.
Just make the static BroadcastReceiver
public class WatchMessageReceiver extends BroadcastReceiver{
#Override
public void onReceive(Context context, Intent intent) {
if (intent != null &&
intent.getAction().equals("com.me.project.wear.to.app")) {
String msg = intent.getStringExtra("Data");
Intent launcherIntent = new Intent(context, LauncherActivity.class);
launcherIntent.putExtra("Data",msg);
startActivity(launcherIntent);
}
}
}
in your manifest file
<receiver android:name ="WatchMessageReceiver"
<intent-filter>
<action android:name="com.me.project.wear.to.app"/>
</intent-filter>
</receiver>
In the Sending and Syncing Data training, there is a Handling Data Layer Events:
When you make a call to the Data Layer API, you can receive the status of the call when it completes. You also can listen for data events, resulting from data changes that your application makes anywhere on the Android Wear network.
Listen for Data Layer Events
Because the data layer synchronizes and sends data across the handheld and wearable, it is usually necessary to listen for important events. Examples of such events include creation of data items and receipt of messages.
To listen for data layer events, you have two options:
Create a service that extends WearableListenerService.
Create an activity that implements DataApi.DataListener.
With both these options, you override the data event callback methods for the events you are interested in handling.
Some of the events you can listen for using WearableListenerService are as follows:
onDataChanged(): Whenever a data item object is created, deleted, or changed, the system triggers this callback on all connected nodes.
onMessageReceived(): A message sent from a node triggers this callback on the target node.
onCapabilityChanged(): When a capability that an instance of your app advertises becomes available on the network, that event triggers this callback. If you're looking for a nearby node you can query the isNearby() method of the nodes provided in the callback.
According to the related SO post:
WearableListenerService does not run constantly - it is only started when a new message/node connection/data layer change is sent and stopped when there are no more messages.
Hope this helps.
I am creating an SMS app. I can send messages fine, however I cannot get it to receive. I have successfully implemented the functionality to allow the app to be selected as the default SMS application on the device.
The problem I have is that I cannot pass the SMS from the BroadcastReceiver to the Activity that displays messages. I am aware of the ability to use intent.putExtra() for the message and then startActivity(), but what happens if that activity has already been started when the message is received? I do not want to restart the activity every time a new message is received.
There are few ways to skin that cat, one way is to have a receiver inside the Activity something like this
void onResume(){
super.onResume();
IntentFilter filter = new IntentFilter();
filter.addAction("android.provider.Telephony.SMS_RECEIVED");
registerReceiver(mSmsReceiver, filter);
}
void onPause(){
super.onPause();
unregisterReceiver(mSmsReceiver);
}
private BroadcastReceiver mSmsReceiver = new BroadcastReceiver() {
#Override
public void onReceive(Context context, Intent intent) {
//Do you stufff
}
};
I am trying to develop a android chat application using asmack api and server is openfire.
I am at the stage of handling incoming messages from users and representing them corresponding user chat screen (i.e. activity).
So for that, I developed 2 activities i.e.
public class ResultActivity extends Activity
public class UserActivity extends Activity
resultactivity is the one which maintains roster presence information like online , away etc. so this would be only one instance.
useractivity is the one which maintain chat list with the corresponding user. This activity starts with onclick event on list in ResultActivity. so this can be more than one based on no of users on Result activity..
So to listen to incoming packets (i.e. incoming messages) I added a listener in the ResultActivity which adds messages into global arraylist.
In Result Activity:
PacketFilter filter = new MessageTypeFilter(Message.Type.chat);
MainActivity.connection.addPacketListener(receive_message, filter);
PacketListener receive_message = new PacketListener() {
public void processPacket(Packet packet) {
message = (Message) packet;
String sender=null,body=null,sender_final=null;
if (message.getBody() !=null) {
Log.d("UA", "message from "+StringUtils.parseBareAddress(message.getFrom()));
Log.d("UA", "message is "+message.getBody());
sender = StringUtils.parseBareAddress(message.getFrom());
sender_final=sender.substring(0, sender.indexOf('#'));
body = message.getBody();
Log.d("UA", "Sender : "+sender_final+" body : "+body);
userMessage = new UserMessage("In", sender_final, body);
userMessage_list.add(userMessage);
userMessage_list.add(userMessage);
}
}
};
After adding the message in the global message list (i.e. userMessage_list) I need to update the user activity with incoming message. userMessage_list is the array list used as array in the getview method of base adapter extended class.
So Now I need the update the userActivity list with notifydatasetchanged method.
In UserActivity :
private class UserActivityThread extends Thread {
#Override
public void run() {
UserActivity.this.runOnUiThread(new Runnable() {
#Override
public void run() {
userAdapter.notifyDataSetChanged();
}
});
}
}
So how to call the notifydatasetchanged method in the another activity.
I am curious to know how this scenario is handled in whatsapp or any chat applications.
I have solved this problem in my chat app by using a ContentProvider class and a CursorLoaderwhich will be automatically notified everytime certain URI has new records.
In your case I would recommend you launching a broadcast message. Your class which has a ListView with the messages will have registered a BroadcastReceiver and it will be listening to possible updates. Everytime your BroadcastReceiver.onReceive is triggered in your activity, refresh your adapter.
Hope it helps :)
EDIT
How to achieve this:
Create a BroadcastReceiver object in your activity.
BroadcastReceiver mReceiver;
Code your broadcast receiver (on your onCreate for example)
mReceiver = new BroadcastReceiver() {
#Override
public void onReceive(Context context, Intent intent) {
//extract our message from intent
String extra= intent.getStringExtra("extra");
Log.i("msg received: ", extra);
}
};
Add IntentFilter (in your onResume could be valid)
IntentFilter intentFilter = new IntentFilter("com.myproject.myintentfilter");
4.1 register your receiver
#Override
protected void onResume() {
// TODO Auto-generated method stub
super.onResume();
registerReceiver(mReceiver,intentFilter);
}
4.2 Unregister your receiver
#Override
protected void onPause() {
// TODO Auto-generated method stub
super.onPause();
this.unregisterReceiver(mReceiver);
}
Make sure your receiver will receive the message, cheking that your sendBroadcast matches the IntentFilter.
Finally:
Intent i = new Intent("com.myproject.myintentfilter").putExtra("extra", "This is a new value");
this.sendBroadcast(i);
EDIT 2
In the case of receiving a message during your activity rotation (receiver is not registered) I have found 2 solutions which I am not very satisfied with, but they work.
Reload your listview after orientation change, as the activity destroys itself, you can just reload the information of your listview, your new message should appear anyway.
Put a static field in your activity, everytime you receive a message, put such variable to TRUE. If your broadcastReceiver triggers, put that variable to false, and when your onResume / onCreate method is called after a change of orientation, check your static variable and do your reload if the variable was true (put it to false after reloading the ListView).
I am able to receive C2DM message fine but I want to send the data to a running activity, i.e when the activity is running, if the receiver receives C2DM message it is to send the data to the running activity. The code of receiver is (no bugs in the code):
public class C2dmreceiver extends BroadcastReceiver {
#Override
public void onReceive(Context context, Intent intent) {
String action = intent.getAction();
Log.w("C2DM", "Message Receiver called");
if ("com.google.android.c2dm.intent.RECEIVE".equals(action))
{
final String payload = intent.getStringExtra("key1");
Log.d("C2DM", "message = " + payload );
}
}}
I have tried like this inside the activity in an attempt to register the receiver in the activity so that the receiver can send data and the running activity can receive the data :-
C2dmreceiver c2dmr = new C2dmreceiver();
Registration.this.registerReceiver(c2dmr, new IntentFilter());
I don't know what to put inside the IntentFilter(), also what else I have to put in the code of the activity and the code of the receiver so that while the activity is running and some C2DM message comes the receiver can send the data to the running activity.
So, please tell me the code that is to put in the activity and in the receiver and may also be in the manifest so that the data from the receiver could be send to running activity.
Any advice is highly appreciated.
First of all it's not the best idea to subscribe c2dm receiver in activity. Do it in manifest. For passing data to activity you can create static string field in Activity and set you String there.
You can do something like this:
in Activity
public static YourActivity mThis = null;
#Override
protected void onResume() {
super.onResume();
mThis = this;
}
#Override
protected void onPause() {
super.onPause();
mThis = null;
}
In your BroadcastReceiver:
#Override
public void onReceive(Context context, Intent intent) {
...
if (YourActivity.mThis != null) {
((TextView)YourActivity.mThis.findViewById(R.id.text)).setText("received c2dm");
}
else {
...
}
i have a android service running in the background which receives the coordinates from the server every few seconds. i am not sure how do i display the coordinates on a map every time the service receives a response from the server. kindly help or give an idea.
thanks
I don't know any tutorials on this, but here's a version of mine:
To send a broadcast, you use the 'sendBroadcast(Intent i)' method of the Context class. The Service class extends Context, so you can access it from your implementation.
So in your Service goes:
public static final String BROADCAST_ACTION="com.yourservice.update";
public void onStart( Intent intent, int startId ) {
...
Intent broadcastIntent = new Intent(BROADCAST_ACTION);
sendBroadcast(broadcastIntent);
...
}
You have to register a receiver for this broadcast in you Activity (possibly before you start boradcasting them), like this:
private BroadcastReceiver receiver=new BroadcastReceiver() {
public void onReceive(Context context, Intent intent) {
//Here goes handling the stuff you got from the service
Bundle extras = intent.getExtras();
if(extras != null)processUIUpdate(extras);
}
};
public void onResume() {
...
//Register for the update broadcasts from the torrent service
registerReceiver(receiver, new IntentFilter(YourService.BROADCAST_ACTION));
...
}
Don't forget to deregister when the Activity goes background:
public void onPause() {
...
//Deregister for the update broadcast from the torrent service
unregisterReceiver(receiver);
...
}
This should work.
Your service could broadcast intents whenever it wants to update the displayed location on the map. The Activity displaying the map should register a receiver for that boradcast, and the boradcast's intent can hold the values for lat. and long.