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Android Change a variable in service from other app

the title says all, I need to change the variable of my service from a activity in my other app , what to finalize the service or not, this is possible?
I found the Message object , but I do not quite understand

The simplest solution would be to implement a BroadcastReceiver. Your Service listens for the Broadcast and the other App sends the Broadcast.
Example Reciever:
public class MyReceiver extends BroadcastReceiver {
#Override
public void onReceive(Context context, Intent intent) {
// Get bundle from intent and use it to set your Variable in your Service
}
}
Example Broadcaster (courtesy of Vogella):
Intent intent = new Intent();
intent.setAction("de.vogella.android.mybroadcast");
sendBroadcast(intent);

Calling a Activity method from BroadcastReceiver in Android when BroadcastReceiver app is not started

I have a Broadcastreceiver in my ReceiverApp, which I call from my SenderApp and this works fine.
I would like to call a method of the Activity in my ReceiverApp.
How can I do that with the following prerequisites ? :
The ReceiverApp was not started and dynamically registering the receiver is not possible.
I can't call the Receivers Mainactivity from my Sender, because I would like to prevent showing any ActivityScreen of the Receiver. The Sender should just call an ReceiverActivity method and proceed further, so the Senderscreen should be always on top.
I cant do the ReceiverActivity Method "static", because then I loose the context of the Activity. I need for example to fetch the Packagename of the Receiver with : this.getPackageName()
public class MyBroadcastReceiver extends BroadcastReceiver {
#Override
public void onReceive(Context context, Intent intent) {
// TODO Auto-generated method stub
// Extract data included in the Intent
CharSequence intentData = intent.getCharSequenceExtra("message");
Toast.makeText(context, "Say : "+intentData, Toast.LENGTH_LONG).show();
MainActivity.myMethod(); <<<<<--------
}
}
Any hint or help ?

By definition, what you want is impossible. If the activity does not exist, you cannot call methods on it.
Move your code to some common location that is accessible from both the receiver and the activity, such as a static method.
I cant do the ReceiverActivity Method "static", because then I loose the context of the Activity.
Pass a Context as a parameter to the method.
I need for example to fetch the Packagename of the Receiver with : this.getPackageName()
Call getPackageName() on the Context that is passed into onReceive().

Broadcast Receiver class and registerReceiver method

Hi i am trying to understand Broadcast Receiver , i went through many sample codes , but still have some doubts. I wanted to know when we have to extend the Broadcast Receiver class and when should we use registerReceiver() method and when should we create object for BroadcastReceiver. In some programs i came across registerReceiver methods being used but without extending the Broadcast Receiver class. I also wanted to know how the onReceive method gets called.
Which approach should be used when?
here is the registerReceiver method:
registerReceiver(new BroadcastReceiver() {
#Override
public void onReceive(Context context, Intent intent) {
switch (getResultCode()) {
........
}
}
}, new IntentFilter(SENT));
Object being created for BroadcastReceiver:
private BroadcastReceiver intentReceiver = new BroadcastReceiver() {
#Override
public void onReceive(Context context, Intent intent) {
.................
}
};

Android has intent action for broadcast receiver. BroadCast receiver will be trigger when it listen any action which registered within it.
Now we will take one example :
That we need to listen the action of "whenever any bluetooth device connect to our device". For that android has it fix action android.bluetooth.BluetoothDevice.ACTION_ACL_CONNECTED
So you can get it via manifest & registration also
BY Manifest Registration:
Put this in your manifest
<receiver android:name="MyBTReceiver">
<intent-filter>
<action android:name="android.bluetooth.BluetoothDevice.ACTION_ACL_CONNECTED" />
</intent-filter>
</receiver>
Create MyBTReceiver.class
public class MyBTReceiver extends BroadcastReceiver {
#Override
public void onReceive(Context context, Intent intent) {
if(intent.getAction().equals("android.bluetooth.BluetoothDevice.ACTION_ACL_CONNECTED")){
Log.d(TAG,"Bluetooth connect");
}
}
}
That was the simplest broadcast Receiver.
Now,
if you are only interested in receiving a broadcast while you are running, it is better to use registerReceiver(). You can also register it within your existing class file. you also need to unregister it onDestroy().
here, you dont need any broadcast registration in manifest except activity registration
For example
public class MainActivity extends Activity {
IntentFilter filter1;
#Override
public void onCreate() {
filter1 = new IntentFilter("android.bluetooth.BluetoothDevice.ACTION_ACL_CONNECTED");
registerReceiver(myReceiver, filter1);
}
//The BroadcastReceiver that listens for bluetooth broadcasts
private final BroadcastReceiver myReceiver = new BroadcastReceiver() {
#Override
public void onReceive(Context context, Intent intent) {
if(intent.getAction().equalsIgnoreCase("android.bluetooth.BluetoothDevice.ACTION_ACL_CONNECTED")) {
Log.d(TAG,"Bluetooth connect");
}
}
};
#Override
public void onDestroy() {
unregisterReceiver(myReceiver);
}
}

In both cases BroadcastReceiver will be extended. In your second example you create so called anonymous class. New class has no specific name, that is why it's called so. Anyway this new class extends BroadcastReceiver and overrides onReceive() method.
Now back to your question. There are two kinds of receivers - statically and dynamically defined ones.
If you declare your receiver in AndroidManifest file, then it is statically defined. In this case you need to refer to a class implementing BroadcastReceiver by name. As you can see, you cannot use an anonymous class, because the last has no name. You have to explicitly implement a receiver. It's worth to mention, that in this case you do not use registerReceiver() method. Android does it for you automatically.
If you declare receivers dynamically (for instance in activity's onResume() method), then you can use anonymous class for that. To register a receiver you call registerReceiver() method. You can also use a named class too. Both options are valid in this case.
Hope this explains the difference.

In both case you are creating object.But in first case there is not any reference for
the receiver object so it can not be unregistered later but second one has so it can be
unregistered after registering object using below methods:
registerReceiver(intentReceiver );
unregisterReceiver(intentReceiver );

How to execute methods from a running service from broadcast?

on a broadcast I want to call a non static method from Service XYZ. The Service is start by the receiver on boot.
Has someone a idea to run methods from this running service?
One solution in this forum is to make the method static and use a singleton pattern to execute. But is there another method? Maybe with a binder?
//EDIT for example i have the following clases:
public class MyService extends Service{
.....
public void method(){
//TODO
}
}
public class MyBroadcastReceiver extends BroadcastReceiver{
.....
public void onReceive(Context context, Intent intent) {
String intentAction=intent.getAction();
if(intentAction.equals(Intent.ACTION_BOOT_COMPLETED)){
//start service
Intent serviceIntent = new Intent(context, MyService.class);
context.startService(serviceIntent);
}
else{
//TODO call method() in MyService
}
}
how can i call the method method()? I know that i can cast with context.getSystemService() system services. But how can i get my own service object?
greetings

You can add an action string to your intent using setAction in the intent that launches the Service. In your service's onStartcommand you can extract the intent's action, and based off that you can execute the method in your service.
You will always send commands to your service using startService this will not launch your service twice. It will either get started once, or the new intent is sent to the service.
So, in your on boot completed section you should set the intent action to whatever you want, and start the service - you can remove the else block completely.
In your Service implement the onStartCommand, extract the intent's action, and based off that action you can just execute your method.

Android Communication between Broadcast Receiver and MainActivity (Send data to activity)

I've a simple Main Activity which has to stop till an SMS is received... How can I launch a method from the MainActivity within the BroadcastReceiver's onReceive() Method?
Is there away with Signal and Wait? Can I pass something with a pending Intent, or how can I implement this communication?

Communication from BroadcastReceiver to Activity is touchy; what if the activity is already gone?
If I were you I'd set up a new BroadcastReceiver inside the Activity, which would receive a CLOSE message:
private BroadcastReceiver closeReceiver;
// ...
closeReceiver = new BroadcastReceiver() {
#Override
public void onReceive(Context context, Intent intent) {
//EDIT: receiving parameters
String value = getIntent().getStringExtra("name");
//... do something with value
finish();
}
};
registerReceiver(closeReceiver, new IntentFilter(CLOSE_ACTION));
Then from the SMS BroadcastReceiver you can send out this action:
Intent i = new Intent(CLOSE_ACTION);
i.putExtra("name", "value"); //EDIT: this passes a parameter to the receiver
context.sendBroadcast(i);
I hope this helps?

I had the exact same problem, I tried using intent but i was unsuccessful
The easiest way to use it would be using static methods and static variables
MainActivity.java
public static void stopsms()
{
/*
some code to stop the activity
*/
}
SMSReceiver.java
at the end call this function
MainActivity.stopsms();
It works amazing if your code does not affect when you use static methods and variables. Let me know if you need any help.

The problem with registering a second receiver within the activity, however, is that it will not be persistent like registering in the manifest... thus, although, this solution may work, will only work if the activity is running in background.

it's easy, use interface like that:
1) in your broadcast receiver create an interface.
public interface ChangeListener{
public void functionWhoSendData(String type);
public void etc();
}
and instantiate that interface in your broadcast receiver, use it:
public void onReceive(....
String data=functionWhereYouReceiveYouData();
ChangeListener.functionWhoSendData(data);
}
And in your activity, make it implements your interface