Give user feedback on EditTexts with limited InputType

Question

I have an EditText with a restricted InputType, like this: latEdit.setInputType(InputType.TYPE_CLASS_NUMBER | InputType.TYPE_NUMBER_FLAG_DECIMAL);

This only accepts float/double values.

So when a user tries to type characters that are not allowed, nothing happens.
I would like to give the user feedback when that happens. E.g. "only decimals allowed" in a toast.

---

My guess would have been to use onTextChanged and try to validate the input there, but I'm not sure that method would even be called with restricted input.

---

EDIT
I used the idea of M.Saad Lakhan's answer, removed the setInputType flags and solved it with this regex and the setError method:

public void onTextChanged(CharSequence s, int start, int before, int count) {
        if (!s.toString().matches("[0-9]{1,13}(\\.[0-9]*)?"))
        {
            latEdit.setError(wrongInputWarning);
        }
    }

Answer 1

You dont need to do that:

latEdit.setInputType(InputType.TYPE_CLASS_NUMBER | InputType.TYPE_NUMBER_FLAG_DECIMAL);

You need to addTextChangeListener on your edit text as follows:

yourEditText.addTextChangedListener(new TextWatcher() {
    @Override
    public void beforeTextChanged(CharSequence s, int start, int count, int after) {

    }

    @Override
    public void onTextChanged(CharSequence s, int start, int before, int count) {
       if (!s.matches("(?<=^| )\d+(\.\d+)?(?=$| )"))
            {
                Toast.makeText(getApplicationContext(), "Only digits and . are allowed", Toast.LENGTH_LONG).show();
                etNewPassword.requestFocus();
                return;
            }
    }

    @Override
    public void afterTextChanged(Editable s) {
        textv.setText(s);
    }
});

In on text changed you have to apply checks according to your requirements