How do I restrict my EditText input to numerical (possibly decimal and signed) input?

Question

I have read Android: Limiting EditText to numbers and How do I show the number keyboard on an EditText in android?. Unfortunately, none of them seems to fit my needs.

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Answer 1

my solution:`

   public void onTextChanged(CharSequence s, int start, int before, int count) {
   char ch=s.charAt(start + count - 1);
   if (Character.isLetter(ch)) {
       s=s.subSequence(start, count-1);
       edittext.setText(s);
    }