Question

I want to filter a ListView in real time. I have an EditText in the ActionBar, and each time the user writes a character I want to update the cursor of the ListView filtering the information.

I have done an AsyncTask to perform the query but I have two questions:

1º) If the user types three characters I’m creating three AsyncTasks (one to search the first character, one to search the two first characters, and finally one to search the three characters). Is there a simple way to say to the AsyncTask to replace the previous task with the new one?

2º) How can I put a small delay to start the AsyncTask? So if the user types three characters without stopping, I will not create the AsyncTask until the end.

Thanks!

Answer 1

Hmmm…Not totally sure why your using AsyncTask for search in real-time. Here’s how I would(and have successfully) do it.

Add a TextChangeListener to your Edittext:

editText.addTextChangedListener(new TextWatcher() {

        @Override
        public void onTextChanged(CharSequence s, int start, int before, int count) {
            searchResults = myDbHelper.searchAll(s.toString());
            searchAdapter.notifyDataSetChanged();
        }

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

        }

        @Override
        public void afterTextChanged(Editable s) {
            // TODO Auto-generated method stub

        }
    });

I am searching through a sqlite database everytime a user presses a key. My searchResults is used to populate the ListView, and so after I set the get the search results, tell the list adapter that the data set changed.

Hope this helps.