Set text on textView in background process

Question

So, I have my application which has BroadcastReceiver and receives notification from other application. The problem is, I am receiving a message, displaying it in the phone via Toast, but I want to set it visible on my TextView. I have only two classes in my whole app.

My receiver is my own class which extends BroadcastReceiver and its onReceive method looks like this:

@Override
public void onReceive(Context context, Intent intent) {
    String value =  intent.getExtras().getString("hiddenMessage");
    MainActivity.getInstace().updateTheTextView(value);
}

Here's the code of the method which updates textView. This method is in MainActivity class:

public void updateTheTextView(final String textFromNotification) {
    final Context context = this;

    Toast toast = Toast.makeText(context, "Message received: " + textFromNotification, Toast.LENGTH_LONG);
    toast.show();

    ((Activity) context).runOnUiThread(new Runnable() {
        @Override
        public void run() {
            textV1.setText(textFromNotification);
        }
    });
}

The problem is, when I send a notification from one app and receive it here, text is not visible. It's only visible when this app is open. How can I set text to field when my app is not open? Store message to some class field and use setText() in onResume method?

Where is the above code located? Is the broadcast receiver instance created and registered/unregistered in the same class? — clownba0t, Nov 13 '16 at 17:36

score 1 · Answer 1 · edited May 23 '17 at 12:07

In your onReceive method after getting String value store it in sharedPreference like this

public void saveInSharedPreferences(String value){
    SharedPreferences sharedpreferences = getSharedPreferences("sharedPref", Context.MODE_PRIVATE);
    SharedPreferences.Editor editor = sharedpreferences.edit();
    editor.putString("variable",value);//your String value
    editor.commit();
}

your onReceive method will be like

public void onReceive(Context context, Intent intent) {
    String value =  intent.getExtras().getString("hiddenMessage");
    saveInSharedPreferences(value);
}

and in your Activity's onCreate method

protected void onCreate(Bundle savedInstanceState) {
     super.onCreate(savedInstanceState);

     String value = getValueFromSharedPreference();
     if(value != null){
          textview.setText(value);
     }
}

getValueFromSharedPreference method

public String getValueFromSharedPreference(){
         SharedPreferences sharedpreferences = getSharedPreferences("sharedPref", Context.MODE_PRIVATE);

         return sharedpreferences.getString("variable",null);
}

Now if you want to update Textview when your app is open
Try this

public void onReceive(Context context, Intent intent) {
    String value =  intent.getExtras().getString("hiddenMessage");
    saveInSharedPreferences(value);
    Intent intent = new Intent("broadcast");
    intent.putExtra("variable",value);
    context.sendBroadCast(intent);
}

and then in your Activity's oncreate method

registerReceiver(broadcastReceiver, new IntentFilter("broadcast"));

and then in Your Activity's Class outside oncreate Method

BroadcastReceiver broadcastReceiver = new BroadcastReceiver() {
    @Override
    public void onReceive(Context context, Intent intent) {

          String value = intent.getStringExtra("variable");
          textview.setText(value);
    }
};

or you can even use this interface solution:https://stackoverflow.com/a/26268569/6799807

As I understand, this will update my textView when I open the application. What if my app is already opened? — TheOpti, Nov 13 '16 at 18:35
Another question is, how can I use method getSharedPreferences in a separate class which only extends BroadcastReceiver? getSharedPreferences is from Context...? — TheOpti, Nov 13 '16 at 18:43
you can put saveInSharedPreferences method in your class which extends BroadcastReceiver class and then in sharedpreference use context — Rajesh Gosemath, Nov 13 '16 at 19:13
One more question is: how can I create a notification from onReceive method so that it will open my application and show message? — TheOpti, Nov 13 '16 at 21:56

score 0 · Answer 2 · answered Nov 13 '16 at 18:31

First in onRecieve Method save the detail in sql

   private void saveNotification(String msg) {
   //notification_sql class to save detail
    Notification_sql n=new Notification_sql(getApplicationContext());
    Notification_detail notification_detail=new Notification_detail();
    //notification detail model class to set and get get detail
    notification_detail.setData(msg);
    n.adddetail(notification_detail);
    }

Second save detail in database

    public String adddetail(Notification_detail dataval){
    SQLiteDatabase db = this.getWritableDatabase();
    ContentValues values = new ContentValues();
    values.put(DATE_OF_ENTRY,dataval.getData());
    // Inserting Row
    db.insert(TABLE_NAME, null, values);
    db.close(); // Closing database connection
    return null;
    }

Get data using task sheduler in Main Activity

    scheduleTaskExecutor= Executors.newScheduledThreadPool(5);
    // This schedule a task to run every 10 minutes:
       scheduleTaskExecutor.scheduleAtFixedRate(new Runnable() {
        public void run() {
            // If you need update UI, simply do this:
            runOnUiThread(new Runnable() {
                public void run() {
                    //update text view
                    Notification_sql meter_data=new Notification_sql(MapsActivity.this);
                    //getting detail from database which is saved just after message delivery
                    List<Notification_detail> contacts = meter_data.getDetail();
                    //System.out.println(contacts);
                    for (Notification_detail cn : contacts) {
                        String data=cn.getData();

                       txtdetail.setText(data)
                    }
                }
            });
        }
      }, 0, 10, TimeUnit.SECONDS);

Set text on textView in background process

2 Answers2