How to avoid multiple triggers on EditText while user is typing?

Question

I use the following code to perform search when user types in an EditText :

EditText queryView = (EditText) findViewById(R.id.querybox);
queryView.addTextChangedListener(new TextWatcher() {
  @Override
  public void afterTextChanged(Editable s) {
    triggerSearch(s.toString()); 
  }
  @Override
  public void beforeTextChanged(CharSequence s, int start, int count, int after) {
  }
  @Override
  public void onTextChanged(CharSequence s, int start, int before, int count) {
  }
});

However, this triggers multiple times when the user is typing a word. That is if the user is typing "hello", this code will trigger 5 times with values ("h", "he" , "hel", "hell", "hello"). Normally, this would be fine but the triggered search is expensive and I don't want to waste resources on intermediate searches that are of no great use. What I want is either a listener that triggers only a certain threshold after the user starts typing, or some kind of framework, that waits in the listener before calling triggerSearch, and if another event is triggered before that wait, cancels itself.

Answer 1

Since couldn't find an appropriate event interface, tried triggering a delayed search. The code is actually pretty simple and robust.

private final int TRIGGER_SERACH = 1;
// Where did 1000 come from? It's arbitrary, since I can't find average android typing speed.
private final long SEARCH_TRIGGER_DELAY_IN_MS = 1000;

  private Handler handler = new Handler() {
    @Override
    public void handleMessage(Message msg) {
      if (msg.what == TRIGGER_SERACH) {
        triggerSearch();
      }
    }
  };

 queryView.addTextChangedListener(new TextWatcher() {

   @Override
   public void beforeTextChanged(CharSequence charSequence, int i, int i2, int i3) {

   }

   @Override
   public void onTextChanged(CharSequence charSequence, int i, int i2, int i3) {

   }

   @Override
   public void afterTextChanged(Editable s) {
    handler.removeMessages(TRIGGER_SERACH);
    handler.sendEmptyMessageDelayed(TRIGGER_SERACH, SEARCH_TRIGGER_DELAY_IN_MS);
   });