Problem Using ScheduledThreadPoolExecutor

[Ya2]

I'm coding a program which calls a servlet, gets Strings in return, and posts the Strings into an EditText.

The code works fine without using the ScheduledThreadPoolExecutor , but when I use it, debugging the servlet shows the request has arrived, and it returns a answer, yet the Android application never posts the String into the EditText.

I want the program to call the servlet every 1 second.
At the moment where the program needs to start polling, this code is activated:

Class data member :

private ScheduledThreadPoolExecutor timer = new ScheduledThreadPoolExecutor(1);

Code in class :

timer.scheduleAtFixedRate(new Runnable() {
public void run() {
try {
String[] recentEvents;
recentEvents = getAllEvents(); // Gets the strings from the servlet
if (recentEvents != null)
activateEvents(recentEvents); // Prints them to the EditText
} catch (IOException e) {
e.printStackTrace();
}
}
}, 100, 1000,TimeUnit.MILLISECONDS);