Android- Problem with an Handler

Question

Hi

I've a multiAutocompleteTextView which I load the adapter list by calling Host. That is to say, when the user write 3 letters in the searchZone, I call Host, and I propose him suggestions in relation to what he write.

I would like to temporize this call. If user write more that 3 letters, The purpose is to wait the end before launch call. (I fell that after 500 ms of inactivity it is the end)

So I use an Handler to do that, but it doesn't work. Either it dosen't do the call, Or it do it but after each letters :/

My code

On the OnCreate :

searchZone.setOnItemClickListener(this);

        // lISTENER key pressed on ZoneOK+multiauocompletetextview
        searchZone.addTextChangedListener(new TextWatcher() {

            @Override
            public void afterTextChanged(Editable s) {
                [...]
            }

            @Override
            public void beforeTextChanged(CharSequence s, int start, int count, int after) {


            }

            @Override
            public void onTextChanged(CharSequence s, int start, int count, int after) {
                try {

                        if (s.length() >= searchZone.getThreshold()) {


                            try{
                                timerHandler.removeCallbacks(callHostToLoadSuggest);
                            }catch(Exception e){
                                timerHandler = new Handler();
                            }


                            // Display Suggestions
                            search_pattern = searchZone.getText().toString();
                            timerHandler.postDelayed(callHostToLoadSuggest, 500);




                } catch (Exception e) {

                    Alerts.showAlert(e.toString(), HeaderMailDisplayActivity.this, true);
                    // TODO Auto-generated catch block
                    e.printStackTrace();
                }
            }
        });

the Runnable :

 final Runnable callHostToLoadSuggest = new Runnable() {
           public void run() {

               displaySuggest(search_pattern);

        }};

Did someone could help me please ? I try to do that for 1 month :/