I want to update an Activity which is not the MainActivity.
So I start a second Activity via a onClick method in MainActivity.
Now the Activty "SecondActivity" is at front.
When I started a Thread in the "MainActivity" how can I reference to the "SecondActivity" to update their TextViews and so on?
PseudoCode
public class activity_MainActivity extends AppCompatActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
ThreadSome threadSome= new ThreadSome();
threadSome.start()
}
onClick(View View){
Intent intent = new Intent(this, activity_Second.class);
startActivity(intent);
}
}
Inside Thread
public class ThreadSome extends Thread {
#Override
public void run() {
//This is what I don't know, so I just write what I want to do.
// I know the following Code is wrong and not working.
activity_Second.someTextView.setText("Hi");
}
}
Is a WeakReference the best way to do this, or better work with static TextView objects? How would you solve this problem?
Based on your description, I think you want to do something where there will be some ui change in activity stack based on some event performed in the forground activity. There is a good way to use onActivityResult() via startActivityForResult() but if this is not fullfilling your requirement directly then you can try something like below:
/**
UpdateActivity is the activity where some ui update or action will be taken based on event in EventActivity.
**/
public class UpdateActivity extends Activity {
private BroadcastReceiver mReceiver;
public static final String ACTION_UPDATE = "com.my.internal.activity.action";
...
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_update);
......
//Prepared Intent for broadcast receiver
IntentFilter intentFilter = new IntentFilter(ACTION_UPDATE);
//registering our receiver
this.registerReceiver(mReceiver, intentFilter);
.....
}
//This is the receiver section where you need to do the ui update
mReceiver = new BroadcastReceiver() {
#Override
public void onReceive(Context context, Intent intent) {
//extract our message from intent
String some_msg = intent.getStringExtra("msg_1"); //parameter received if passed in intent when broadcast called.
//log our message value
Log.i("Message", some_msg);
updateActivityUi();
}
};
private void updateActivityUi() {
// you need to write the code for the update which you want to do after an event done in other activity.
}
#Override
protected void onDestroy() {
super.onDestroy();
//unregister our receiver
this.unregisterReceiver(this.mReceiver);
}
}
public class EventActivity extends Activity {
...
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_event);
......
//Sending BroadcastReceiver against the action ACTION_UPDATE and it will be received by UpdateActivity.
if(condition_for_event) {
Intent i = new Intent(UpdateActivity.ACTION_UPDATE).putExtra("msg_1", "Hey! an event performed here.");
this.sendBroadcast(i);
}
.....
}
....
}
Let me know if it solved your issue.
How to open a dialog when from some non ui module when there might be different activity in display?
Let's say there could be multiple activities stacked, Activity_A, Activity_B, Activity_C. The common service module may running on non ui thread and running into case need to popup a dialog.
It could be done by passing the handler from all active activities to the module and post message to let the activity to pop dialog.
But that need some management in terms of passing the handler and determine who is on top of the view.
Is there a better way?
You can show dailog from non-ui thread using BroadcastReceiver
Understand Flow:
public class Sample extends Activity {
BroadcastReceiver updateUIReciver;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
updateUIReciver = new BroadcastReceiver() {
#Override
public void onReceive(Context context, Intent intent) {
//UI update here
ShowFailedDailog(null, getString(R.string.mms_sending_service_failed_txt));
}
};
IntentFilter filter = new IntentFilter();
filter.addAction("update.from.nonui");
registerReceiver(updateUIReciver, filter);
}
void ShowFailedDailog(String title, String message) {
final Dialog dialog = new Dialog(context);
dialog.requestWindowFeature(Window.FEATURE_NO_TITLE);
dialog.setContentView(R.layout.import_backup_popup);
TextView Save = (TextView) dialog.findViewById(R.id.tOk);
Save.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
dialog.dismiss();
}
});
TextView cancel = (TextView) dialog.findViewById(R.id.tCancel);
cancel.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
dialog.dismiss();
}
});
dialog.show();
}
}
NON UI:
public class NonUiSerive extends Service {
Context context;
#Nullable
#Override
public IBinder onBind(Intent intent) {
return null;
}
#Override
public int onStartCommand(Intent intent, int flags, int startId) {
if (intent != null) {
// ..... your tasks
if (SomeFlagUpdateTrue) {
Intent local = new Intent();
local.setAction("mms.seding.failed");
context.sendBroadcast(local);
}
}
this.stopSelf();
return 0;
}
}
Similarly register receiver all your three class it will update in every activity not restricted to one.
After try out I think the simplest is to use application context to open a activity for dialog. This way it would not care who's the current activity on top.
Intent dialogIntent = new Intent(applicationCotext, DialogActivity.class);
dialogIntent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
applicationCotext.startActivity(dialogIntent);
I'm building a chat application, which uses web socket. I've wrote a service, which is called in Application class. The problem is that, sometimes the mConnection becomes null when I just start the app after the crash. I think that it's because of the service being run on the background even when I quit the app, and when i start it again, it can't create the new service and bind to it.
My questions are: Is it a good way of writing the code? And is there a way to stop the service on the application destroy?
public class MyApplication extends Application{
private final AtomicInteger refCount = new AtomicInteger();
public ConnectionService mConnectionService;
private ServiceConnection mConnection = new ServiceConnection() {
public void onServiceConnected(ComponentName className, IBinder binder) {
ConnectionService.MyBinder b = (ConnectionService.MyBinder) binder;
mConnectionService = b.getService();
Log.d("MyApplication", "MyApplication has been bounded");
}
public void onServiceDisconnected(ComponentName className) {
mConnectionService = null;
Log.d("MyApplication", "MyApplication has been unbounded");
}
};
#Override
public void onCreate() {
Intent intent = new Intent(this, ConnectionService.class);
getApplicationContext().bindService(intent, mConnection, Context.BIND_AUTO_CREATE);
}
public ConnectionService getConnectionService() {
refCount.incrementAndGet();
Log.d("MyApplication", "getConnectionService, current: "+refCount);
return mConnectionService;
}
public void releaseConnectionService() {
if (refCount.get() == 0 || refCount.decrementAndGet() == 0) {
mConnectionService.stopSelf();
Log.d("MyApplication", "MyApplication has been stopped ");
}
Log.d("MyApplication", "releaseConnectionService, current: "+refCount);
}
}
And the another class looks something like this:
public class LobbyActivity extends Activity{
ListView lvContacts;
Gson gson;
LoginData mLoginData;
MyReceiver receiver;
ArrayList<User> users;
LobbyAdapter lobbyAdapter;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
gson = new Gson();
Intent intent = getIntent();
String loginDataJson = intent.getStringExtra("LoginData");
mLoginData = gson.fromJson(loginDataJson, LoginData.class);
getActionBar().setTitle(mLoginData.getUsername());
setContentView(R.layout.activity_lobby);
users = new ArrayList<User>();
lvContacts = (ListView)findViewById(R.id.lvContacts);
lobbyAdapter=new LobbyAdapter(users, this);
lvContacts.setAdapter(lobbyAdapter);
Commands cmd = new Commands(getApplicationContext());
cmd.sendCommand(Commands.COMMAND_GET_MANAGER_LIST);
cmd.sendCommand(Commands.COMMAND_GET_USER_LIST);
receiver = new MyReceiver(new Handler()) {
#Override
public void onReceive(Context context, Intent intent) {
String message = intent.getStringExtra(ConnectionService.MESSAGE);
String notification = intent.getStringExtra(ConnectionService.NOTIFICATION);
if (message!=null){
try {
switch (Utils.getCommand(message)) {
case Commands.COMMAND_GET_USER_LIST:
ArrayList<User> user = new ArrayList<User>();
user = (gson.fromJson(message, UserList.class)).users;
users.addAll(user);
lobbyAdapter.notifyDataSetChanged();
break;
default:
break;
}
} catch (JSONException e) {
e.printStackTrace();
}
}
}
};
LocalBroadcastManager.getInstance(this).registerReceiver(receiver,
new IntentFilter(MainActivity.BROADCAST_ACTION));
}
class UserList{
String cmd;
ArrayList<User> users;
}
#Override
protected void onDestroy() {
super.onDestroy();
((MyApplication)getApplicationContext()).releaseConnectionService();
}
}
The reason why i put the service in the Application class is that i want it to be up as long as the application runs; and also it is needed to be accessed by all the activities.
Is it a good way of writing the code?
I would say that it's not a good programming practice to start Android app components like Service or Activity from Application class. You should start Service from Activity or BroadcastReceiver component. In the end code inside Application onCreate runs because the new process is created for your application when it starts. This happen if you start app from launcher and main Activity starts or BroadcastReceiver has been given a call. At this moment you can start Service from either of them.
And is there a way to stop the service on the application destroy?
You can stop Service from Activity's onDestroy(). If you don't want to stop Service on every configuration change (like screen rotation) you can check in onDestory method whether it is destroying or only reloading through isChangingConfigurations method of Activity and decide to stop or not Service basing on that knowledge.
I am trying to make my own MusicPlayer for android. Where i came to a problem is running some things in background. Main activity manages GUI and up to now all the songs are playing. I wanted to separate GUI and music playing classes. I want to put music managing part in Service and leave other things as they are now.
My problem is that i can't organize communication between Activity and Service as lot of communication is happening between them including moving objects in both directions. I tried many techniques that I searched here on Stack Overflow but every time I had problems. I need Service to be able to send objects to Activity and vice versa. When I add widget i also want it to be able to communicate with Service.
Any tips are appreciated, if you need source code place comment bellow but now in this transition it became chaotic.
Is there any more advanced tutorial on this than calling one method that returns random number from service? :P
EDIT: Possible solution is to use RoboGuice library and move objects with injection
I have implemented communication between Activity and Service using Bind and Callbacks interface.
For sending data to the service I used Binder which retruns the Service instace to the Activity, and then the Activity can access public methods in the Service.
To send data back to the Activity from the Service, I used Callbacks interface like you are using when you want to communicate between Fragment and Activity.
Here is some code samples for each:
The following example shows Activity and Service bidirectional relationship:
The Activity has 2 buttons:
The first button will start and stop the service.
The second button will start a timer which runs in the service.
The service will update the Activity through callback with the timer progress.
My Activity:
//Activity implements the Callbacks interface which defined in the Service
public class MainActivity extends ActionBarActivity implements MyService.Callbacks{
ToggleButton toggleButton;
ToggleButton tbStartTask;
TextView tvServiceState;
TextView tvServiceOutput;
Intent serviceIntent;
MyService myService;
int seconds;
int minutes;
int hours;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
serviceIntent = new Intent(MainActivity.this, MyService.class);
setViewsWidgets();
}
private void setViewsWidgets() {
toggleButton = (ToggleButton)findViewById(R.id.toggleButton);
toggleButton.setOnClickListener(btListener);
tbStartTask = (ToggleButton)findViewById(R.id.tbStartServiceTask);
tbStartTask.setOnClickListener(btListener);
tvServiceState = (TextView)findViewById(R.id.tvServiceState);
tvServiceOutput = (TextView)findViewById(R.id.tvServiceOutput);
}
private ServiceConnection mConnection = new ServiceConnection() {
#Override
public void onServiceConnected(ComponentName className,
IBinder service) {
Toast.makeText(MainActivity.this, "onServiceConnected called", Toast.LENGTH_SHORT).show();
// We've binded to LocalService, cast the IBinder and get LocalService instance
MyService.LocalBinder binder = (MyService.LocalBinder) service;
myService = binder.getServiceInstance(); //Get instance of your service!
myService.registerClient(MainActivity.this); //Activity register in the service as client for callabcks!
tvServiceState.setText("Connected to service...");
tbStartTask.setEnabled(true);
}
#Override
public void onServiceDisconnected(ComponentName arg0) {
Toast.makeText(MainActivity.this, "onServiceDisconnected called", Toast.LENGTH_SHORT).show();
tvServiceState.setText("Service disconnected");
tbStartTask.setEnabled(false);
}
};
View.OnClickListener btListener = new View.OnClickListener() {
#Override
public void onClick(View v) {
if(v == toggleButton){
if(toggleButton.isChecked()){
startService(serviceIntent); //Starting the service
bindService(serviceIntent, mConnection, Context.BIND_AUTO_CREATE); //Binding to the service!
Toast.makeText(MainActivity.this, "Button checked", Toast.LENGTH_SHORT).show();
}else{
unbindService(mConnection);
stopService(serviceIntent);
Toast.makeText(MainActivity.this, "Button unchecked", Toast.LENGTH_SHORT).show();
tvServiceState.setText("Service disconnected");
tbStartTask.setEnabled(false);
}
}
if(v == tbStartTask){
if(tbStartTask.isChecked()){
myService.startCounter();
}else{
myService.stopCounter();
}
}
}
};
#Override
public void updateClient(long millis) {
seconds = (int) (millis / 1000) % 60 ;
minutes = (int) ((millis / (1000*60)) % 60);
hours = (int) ((millis / (1000*60*60)) % 24);
tvServiceOutput.setText((hours>0 ? String.format("%d:", hours) : "") + ((this.minutes<10 && this.hours > 0)? "0" + String.format("%d:", minutes) : String.format("%d:", minutes)) + (this.seconds<10 ? "0" + this.seconds: this.seconds));
}
}
And here is the service:
public class MyService extends Service {
NotificationManager notificationManager;
NotificationCompat.Builder mBuilder;
Callbacks activity;
private long startTime = 0;
private long millis = 0;
private final IBinder mBinder = new LocalBinder();
Handler handler = new Handler();
Runnable serviceRunnable = new Runnable() {
#Override
public void run() {
millis = System.currentTimeMillis() - startTime;
activity.updateClient(millis); //Update Activity (client) by the implementd callback
handler.postDelayed(this, 1000);
}
};
#Override
public int onStartCommand(Intent intent, int flags, int startId) {
//Do what you need in onStartCommand when service has been started
return START_NOT_STICKY;
}
#Override
public IBinder onBind(Intent intent) {
return mBinder;
}
//returns the instance of the service
public class LocalBinder extends Binder{
public MyService getServiceInstance(){
return MyService.this;
}
}
//Here Activity register to the service as Callbacks client
public void registerClient(Activity activity){
this.activity = (Callbacks)activity;
}
public void startCounter(){
startTime = System.currentTimeMillis();
handler.postDelayed(serviceRunnable, 0);
Toast.makeText(getApplicationContext(), "Counter started", Toast.LENGTH_SHORT).show();
}
public void stopCounter(){
handler.removeCallbacks(serviceRunnable);
}
//callbacks interface for communication with service clients!
public interface Callbacks{
public void updateClient(long data);
}
}
Update: July 10 2016
IMO I think using BroadcastReceiver for custom events is better way
as the Messengers mentioned don't handle activity recreation on device
rotation as well as possible memory leaks.
You may create custom BroadCast Receiver for events in the activity, Then you may also use Messengers.
In your Activity
create a MessageHandler class as
public static class MessageHandler extends Handler {
#Override
public void handleMessage(Message message) {
int state = message.arg1;
switch (state) {
case HIDE:
progressBar.setVisibility(View.GONE);
break;
case SHOW:
progressBar.setVisibility(View.VISIBLE);
break;
}
}
}
Now you can have it's instance as
public static Handler messageHandler = new MessageHandler();
Start your Service with this Handler object as an extra data as
Intent startService = new Intent(context, SERVICE.class)
startService.putExtra("MESSENGER", new Messenger(messageHandler));
context.startService(startService);
In your Service you receive this object from the intent and initialize the Messenger variable in Service as
private Messenger messageHandler;
Bundle extras = intent.getExtras();
messageHandler = (Messenger) extras.get("MESSENGER");
sendMessage(ProgressBarState.SHOW);
And then write a method sendMessage to send messages to activity.
public void sendMessage(ProgressBarState state) {
Message message = Message.obtain();
switch (state) {
case SHOW :
message.arg1 = Home.SHOW;
break;
case HIDE :
message.arg1 = Home.HIDE;
break;
}
try {
messageHandler.send(message);
} catch (RemoteException e) {
e.printStackTrace();
}
}
The sample code above shows and hides a ProgressBar in Activity as messages are received from Service.
Intents are good solution for communication between Activitiy and Service.
A fast solution for receive intents in your service is subclassing IntentService class. It handles asynchronous requests expressed as Intents using a queue and worker thread.
For communication from service to Activity you can broadcast the intent but instead of using normal sendBroadcast() from Context, a more efficent way is to use LocalBroadcastManager from support library.
Example service.
public class MyIntentService extends IntentService {
private static final String ACTION_FOO = "com.myapp.action.FOO";
private static final String EXTRA_PARAM_A = "com.myapp.extra.PARAM_A";
public static final String BROADCAST_ACTION_BAZ = "com.myapp.broadcast_action.FOO";
public static final String EXTRA_PARAM_B = "com.myapp.extra.PARAM_B";
// called by activity to communicate to service
public static void startActionFoo(Context context, String param1) {
Intent intent = new Intent(context, MyIntentService.class);
intent.setAction(ACTION_FOO);
intent.putExtra(EXTRA_PARAM1, param1);
context.startService(intent);
}
public MyIntentService() {
super("MyIntentService");
}
#Override
protected void onHandleIntent(Intent intent) {
if (intent != null) {
final String action = intent.getAction();
if (ACTION_FOO.equals(action)) {
final String param1 = intent.getStringExtra(EXTRA_PARAM_A);
// do something
}
}
}
// called to send data to Activity
public static void broadcastActionBaz(String param) {
Intent intent = new Intent(BROADCAST_ACTION_BAZ);
intent.putExtra(EXTRA_PARAM_B, param);
LocalBroadcastManager bm = LocalBroadcastManager.getInstance(this);
bm.sendBroadcast(intent);
}
}
Example Activity
public class MainActivity extends ActionBarActivity {
// handler for received data from service
private final BroadcastReceiver mBroadcastReceiver = new BroadcastReceiver() {
#Override
public void onReceive(Context context, Intent intent) {
if (intent.getAction().equals(MyIntentService.BROADCAST_ACTION_BAZ)) {
final String param = intent.getStringExtra(EXTRA_PARAM_B);
// do something
}
}
};
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
IntentFilter filter = new IntentFilter();
filter.addAction(MyIntentService.BROADCAST_ACTION_BAZ);
LocalBroadcastManager bm = LocalBroadcastManager.getInstance(this);
bm.registerReceiver(mBroadcastReceiver, filter);
}
#Override
protected void onDestroy() {
LocalBroadcastManager bm = LocalBroadcastManager.getInstance(this);
bm.unregisterReceiver(mBroadcastReceiver);
super.onDestroy();
}
// send data to MyService
protected void communicateToService(String parameter) {
MyIntentService.startActionFoo(this, parameter);
}
}
I think there is a problem with the correct answer. I have not enough reputation to comment on it.
Right in the answer:
Activity call bindService() to get pointer to Service is ok. Because service context is maintained when connection is maintained.
wrong in the answer:
service pointer to Activity class to call back is bad way. Activity instance maybe not null during Activity context is being Release => exception here.
solution for the wrong in the answer:
service send intent to Activity. and Activity receiver intent via BroadcastReceiver.
Note:
in this case, Service and Activity in the same Process, you should use LocalBroadcastManager to send intent. It make performance and security better
This is a simple example of communication between activity and service
Activity
MyReceiver myReceiver; //my global var receiver
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.layourAwesomexD);
registerReceiver();
}
//When the activity resume, the receiver is going to register...
#Override
protected void onResume() {
super.onResume();
checkStatusService(); // verficarStatusServicio(); <- name change
registerReceiver();
}
//when the activity stop, the receiver is going to unregister...
#Override
protected void onStop() {
unregisterReceiver(myReceiver); //unregister my receiver...
super.onStop();
}
//function to register receiver :3
private void registerReceiver(){
//Register BroadcastReceiver
//to receive event from our service
myReceiver = new MyReceiver();
IntentFilter intentFilter = new IntentFilter();
intentFilter.addAction(MyService.SENDMESAGGE);
registerReceiver(myReceiver, intentFilter);
}
// class of receiver, the magic is here...
private class MyReceiver extends BroadcastReceiver {
#Override
public void onReceive(Context arg0, Intent arg1) {
//verify if the extra var exist
System.out.println(arg1.hasExtra("message")); // true or false
//another example...
System.out.println(arg1.getExtras().containsKey("message")); // true or false
//if var exist only print or do some stuff
if (arg1.hasExtra("message")) {
//do what you want to
System.out.println(arg1.getStringExtra("message"));
}
}
}
public void checkStatusService(){
if(MyService.serviceStatus!=null){
if(MyService.serviceStatus == true){
//do something
//textview.text("Service is running");
}else{
//do something
//textview.text("Service is not running");
}
}
}
Service
public class MyService extends Service {
final static String SENDMESAGGE = "passMessage";
public static Boolean serviceStatus = false;
#Override
public void onCreate() {
super.onCreate();
serviceStatus=true;
}
#Nullable
#Override
public IBinder onBind(Intent intent) {return null;}
#Override
public int onStartCommand(Intent intent, int flags, int startId) {
//you service etc...
passMessageToActivity("hello my friend this an example of send a string...");
return START_STICKY;
}
#Override
public void onDestroy() {
super.onDestroy();
passMessageToActivity("The service is finished, This is going to be more cooler than the heart of your ex...");
System.out.println("onDestroy");
serviceStatus=false;
}
private void passMessageToActivity(String message){
Intent intent = new Intent();
intent.setAction(SENDMESAGGE);
intent.putExtra("message",message);
sendBroadcast(intent);
}
}
if we don't unregister BroadcastReceiver we will have an error, you need to unregister when the activity go onPause, onStop, onDestroy...
if you don't register BroadcastReceiver when you back to activity, it will not listen anything from the service... the service will send information to BroadcastReceiver but it will not receive anything because it isn't registered.
When you create more than one service, the following services are going to begin in onStartCommand.
You can pass information to service with intent and you get it in onStartCommand
Difference about return in onStartCommand: Difference between START_STICKY and START_REDELIVER_INTENT? and check the official website of google: Services
The best way in this case is to communicate by doing broadcasting from your service for different actions and receiving it in your activity. You can create a custom broadcast and send some codes defining specific events like complete, change, prepare etc...
Most easy and efficient way will be using EventBus from GreenRobot.
Use simple 3 steps:
1 Define events
public static class MessageEvent { /* Additional fields if needed */ }
2 Prepare subscribers: Declare and annotate your subscribing method, optionally specify a thread mode:
#Subscribe(threadMode = ThreadMode.MAIN)
public void onMessageEvent(MessageEvent event) {/* Do something */};
Register and unregister your subscriber. For example on Android, activities and fragments should usually register according to their life cycle:
#Override
public void onStart() {
super.onStart();
EventBus.getDefault().register(this);
}
#Override
public void onStop() {
super.onStop();
EventBus.getDefault().unregister(this);
}
3 Post events:
EventBus.getDefault().post(new MessageEvent());
Very easy yet powerful way is to use EventBus you can add it to your gradle build and enjoy the easy publisher/subscriber pattern .
Consider i am using five screen pages for project "A".Each page is having switching between other pages sequentially one by one,my need is to do close all the page when i am clicking the button "exit" from the page five which is the last one.
I have used this below code,but the problem is only the last page is getting close others are not.
find my code below
Button extbtn = (Button)findViewById(R.id.but_Exit);
extbtn.setOnClickListener(new View.OnClickListener() {
public void onClick(View v) {
Intent intent = new Intent();
setResult(RESULT_OK, intent);
finish();
} });
Thanks for your time!
Make all five activities extend a BaseActivity that registers a BroadcastReceiver at onCreate (and unregisters at onDestroy).
When extbtn is clicked, send a broadcast to all those BaseActivities to close themselves
for example, in your BaseActivity add:
public static final String ACTION_KILL_COMMAND = "ACTION_KILL_COMMAND";
public static final String ACTION_KILL_DATATYPE = "content://ACTION_KILL_DATATYPE";
private KillReceiver mKillReceiver;
#Override
protected void onCreate(Bundle savedInstanceState) {
...
...
mKillReceiver = new KillReceiver();
registerReceiver(mKillReceiver, IntentFilter.create(ACTION_KILL_COMMAND, ACTION_KILL_DATATYPE));
}
#Override
protected void onDestroy() {
super.onDestroy();
unregisterReceiver(mKillReceiver);
}
private final class KillReceiver extends BroadcastReceiver {
#Override
public void onReceive(Context context, Intent intent) {
finish();
}
}
and at extbtn's onClick call:
extbtn.setOnClickListener(new View.OnClickListener() {
public void onClick(View v) {
// send a broadcast that will finish activities at the bottom of the stack
Intent killIntent = new Intent(BaseActivity.ACTION_KILL_COMMAND);
killIntent.setType(BaseActivity.ACTION_KILL_DATATYPE);
sendBroadcast(killIntent);
Intent intent = new Intent();
setResult(RESULT_OK, intent);
finish();
}
});