how can I shift edit text field focus consecutively

Question

I am trying to make a lock screen, the lock screen basically has four edit text fields, these fields basically take numerical input, no problem in providing the numerical part.

Now the problem I am having is that, the text fields should take only one numerical value,and the edit text fields should change focus, right after one field is provided with a value, how can achieve this?

Answer 1

Use the following property to enter only numbers

<EditText android:inputType="number" ... />

or

<EditText
    android:inputType="phone"
    android:digits="1234567890"
    ...
/>

Answer 2

For only allowing numerical input (and also showing the "number"-keyboard), use the inputType -attribute of the EditText class. To only allow entering one digit into the field, you can use the android:maxLength -attibute .

Use a TextWatcher to check if the one digit has been entered into the text field and change the focus to the next field.

Answer 3

Add a listener to each EditText for when the text changes (make sure the EditText enforces a max length of 1). The logic of this listener will check that the text is a digit and of length 1, then it'll shift focus. Here's the code:

EditText et1 = ...;
EditText et2 = ...;
EditText et3 = ...;
EditText et4 = ...;

et1.addTextChangedListener(new TextWatcher() {
   @Override
   public void onTextChanged(CharSequence s, int start, int before, int count) {
      if( s.length() == 1 && Character.isDigit(s.charAt(0)) ) {
         et2.requestFocus();
      }
   }

   @Override
   public void afterTextChanged(Editable e) { }

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

et2.addTextChangedListener(new TextWatcher() {
   @Override
   public void onTextChanged(CharSequence s, int start, int before, int count) {
      if( s.length() == 1 && Character.isDigit(s.charAt(0)) ) {
         et3.requestFocus();
      }
   }

   @Override
   public void afterTextChanged(Editable e) { }

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

et3.addTextChangedListener(new TextWatcher() {
   @Override
   public void onTextChanged(CharSequence s, int start, int before, int count) {
      if( s.length() == 1 && Character.isDigit(s.charAt(0)) ) {
         et4.requestFocus();
      }
   }

   @Override
   public void afterTextChanged(Editable e) { }

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