How to Apply the Textchange event on EditText

Question

I developed one simple app, like subtraction, addition. In this app I use three EditTexts, one for answer and other two for question. I want to calculate the answer of quest

Answer 1

i think the best in case the edittext type is number... use the (length function) of parameter instead of (equle() function) ex:

edittext.addTextChangedListener(new TextWatcher() {

    public void onTextChanged(CharSequence s, int start, int before,
            int count) {
        if (s.length() > 0)
                { //do your work here }
        }

    }

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

    }

    public void afterTextChanged(Editable s) {

    }
});