Android – can I combine my code into some kind of “global activity”?

Is there any global activity on Android that I put my code in one activity that will affect all activities in my project? This happens to me because the same code is in keyevent.keycode_ Written in several activities such as back

For example, I use here:

public boolean onKeyDown(int keyCode, KeyEvent event) {
        if ((keyCode == KeyEvent.KEYCODE_BACK)) {
            try {
                final Intent itnt_BackServices = new Intent(this,
                        BackServices.class);
                AlertDialog.Builder alert@R_372_2419@ = new AlertDialog.Builder(this);
                alert@R_372_2419@.setTitle("Touch signs");
                alert@R_372_2419@.setMessage("Do you want to quit!");
                alert@R_372_2419@.setPositiveButton("Yes",
                        new DialogInterface.OnClickListener() {
                            public void onClick(DialogInterface arg0, int arg1) {
                                stopService(itnt_BackServices);
                                mPlayer.stop();

                                finish();
                            }
                        });
                alert@R_372_2419@.setNegativeButton("No",
                        new DialogInterface.OnClickListener() {
                            public void onClick(DialogInterface arg0, int arg1) {
                            }
                        });
                alert@R_372_2419@.show();
            } catch (Exception e) {
                // TODO: handle exception
            }
        }
        return false;
    }

I copy and paste it in each activity. I prefer to use some kind of global activity

resolvent:

You can create a class that extends activity, and then extend customactivity to all activity classes, just like this

public abstract class CustomActivity extends Activity{

    public abstract void initComponents();  // you can create a abstract method
    public abstract void addListner();       // you can create a abstract method

    @Override
    public boolean onKeyDown(int keyCode, KeyEvent event) {

         if ((keyCode == KeyEvent.KEYCODE_BACK)) {
              // your stuff here....
            }
        return true;
    }
}

You can now extend this class using activity to extend any class