Unable to update View in addTextChangedListener()

Question

I am trying to edit the background of a Button depending on the length of text in EditText. If the length of text is 0 then the background should be translucent else it should be opaque. However, I am not able to update the Button's background dynamically. If I tap somewhere else on the screen then the button's background is updated, but not in real time.

Here is the code I am using.

emailEditText.addTextChangedListener(new TextWatcher(){

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

        public void beforeTextChanged(CharSequence s, int start, int count,
                int after) {
            // TODO Auto-generated method stub
        }

        public void onTextChanged(CharSequence s, int start, int before,
                int count) {

            if(s.length()!=0){
                submitEmail.getBackground().setAlpha(255);
            }
            else{
                submitEmail.getBackground().setAlpha(45);
            }


        }

    });

Any help will be highly appreciated.

Try this: http://stackoverflow.com/a/8643545/450534. It is not a solution for setting the Alpha in the `TextWatcher`, but for setting the Alpha itself. — Siddharth Lele, Mar 15 '13 at 06:33
Thanks Naveen. I tried `submitEmail.requestLayout()`, but it is not helping me solve the problem. — Dinesh Singh, Mar 15 '13 at 06:36
Thanks Siddharth. I was successfully able to add Alpha. The main problem is that I am not able to do that in `TextWatcher`. — Dinesh Singh, Mar 15 '13 at 06:39

score 1 · Accepted Answer · answered Mar 15 '13 at 07:02

Please do this call after setting the value

    public void onTextChanged(CharSequence s, int start, int before,
            int count) {

        if(s.length()!=0){
            submitEmail.getBackground().setAlpha(255);
        }
        else{
            submitEmail.getBackground().setAlpha(45);
        }

        submitEmail.invalidate();

    }

Unable to update View in addTextChangedListener()

1 Answers1