title: TextInput : when maxLength is full automatically focus next field
body: <p>I have an issue in my app with TextInput for a bank card numbers digit (error because user not type all number 16 digits).</p>
  
  <p>So I would like to cut CB number on 4 TextInputs and focus automatically on next field after filled the 4 digits. (as already seen it in the web app)</p>
  
  <p>But when I focused the next field, the current became empty, even if the state is correctly set.</p>
  
  <p>Do you have an idea about how can I do that or is it impossible ?</p>
  
  <p>ie. see the onChangeText on this example (exp date actually) :</p>
  
  <pre><code>&lt;TextInput
      ref='card_exp_date_mm'
      style={[styles.inputTxt, {width: 30, flex: 0}]}
      value={this.state.cardExpDateMonth}
      keyboardType='numbers-and-punctuation'
      placeholder='MM'
      returnKeyType='next'
      clearTextOnFocus={false}
      autoCorrect={false}
      placeholderTextColor={Constants.placeholderTextColor}
      maxLength={2}
      enablesReturnKeyAutomatically={true}
      blurOnSubmit={false}
      onChangeText={text =&gt; {
        this.setState({cardExpDateMonth: text})
        //console.log('onChangeText', this.refs.card_exp_date_mm)
        if(text &amp;&amp; text.length == 2){
          this.refs.card_exp_date_aa.focus();
        }
      }}
      onSubmitEditing={()=&gt;this.refs.card_exp_date_aa.focus()}/&gt;
  </code></pre>