fcs/lib/pages/signin_page.dart

import 'package:country_code_picker/country_code_picker.dart';
import 'package:flutter/material.dart';
import 'package:flutter/services.dart';
import 'package:font_awesome_flutter/font_awesome_flutter.dart';

import '../theme/theme.dart';
import '../widget/local_text.dart';
import '../widget/progress.dart';
import 'code_page.dart';
import 'util.dart';

class SigninPage extends StatefulWidget {
  @override
  _SigninPageState createState() => _SigninPageState();
}

class _SigninPageState extends State<SigninPage> {
  bool _isLoading = false;
  String dialCode;

  TextEditingController phonenumberCtl;

  @override
  void initState() {
    super.initState();
    phonenumberCtl = new TextEditingController(text: "09");
    phonenumberCtl.selection = TextSelection.fromPosition(
        TextPosition(offset: phonenumberCtl.text.length));

    dialCode = "+95";
  }

  @override
  Widget build(BuildContext context) {
    return LocalProgress(
      inAsyncCall: _isLoading,
      child: new Scaffold(
        appBar: AppBar(
          backgroundColor: primaryColor,
        ),
        body: _buildLogin(context),
      ),
    );
  }

  Widget _buildLogin(BuildContext context) {
    return ListView(
      padding: EdgeInsets.only(top: 5, left: 15, right: 15),
      children: <Widget>[
        Container(
          padding: EdgeInsets.only(top: 40),
          child: LocalText(
            context,
            'login.title',
            fontSize: 21,
            color: secondaryColor,
            fontWeight: FontWeight.bold,
          ),
        ),
        Container(
          padding: EdgeInsets.only(top: 25),
          child: LocalText(
            context,
            'login.phone',
            color: labelColor,
            fontSize: 16,
          ),
        ),
        Row(
          children: <Widget>[
            Container(
              decoration: BoxDecoration(
                  border: Border.all(color: Colors.grey[400], width: 1),
                  borderRadius: BorderRadius.all(Radius.circular(12.0))),
              child: CountryCodePicker(
                onChanged: _countryChange,
                initialSelection: dialCode,
                countryFilter: ['+95', '+65', '+66'],
                showCountryOnly: false,
                showOnlyCountryWhenClosed: false,
                alignLeft: false,
                textStyle: TextStyle(
                  fontSize: 16,
                ),
              ),
            ),
            SizedBox(
              width: 10,
            ),
            Flexible(
              child: Container(
                  padding: EdgeInsets.only(top: 10, bottom: 10),
                  child: TextFormField(
                    autofocus: true,
                    controller: phonenumberCtl,
                    cursorColor: primaryColor,
                    keyboardType: TextInputType.phone,
                    textAlign: TextAlign.left,
                    style: TextStyle(
                      fontSize: 18,
                    ),
                    decoration: InputDecoration(
                      contentPadding: EdgeInsets.all(8.0),
                      enabledBorder: OutlineInputBorder(
                        borderRadius: BorderRadius.all(Radius.circular(12.0)),
                        borderSide:
                            BorderSide(color: Colors.grey[400], width: 1),
                      ),
                      focusedBorder: OutlineInputBorder(
                        borderRadius: BorderRadius.all(Radius.circular(10.0)),
                        borderSide: BorderSide(
                          color: Colors.grey[400],
                        ),
                      ),
                    ),
                  )),
            ),
          ],
        ),
        SizedBox(
          height: 20,
        ),
        Container(
          child: Row(
            mainAxisAlignment: MainAxisAlignment.end,
            children: <Widget>[
              InkWell(
                onTap: () => _next(),
                child: CircleAvatar(
                  minRadius: 25,
                  backgroundColor: primaryColor,
                  child: Icon(
                    FontAwesomeIcons.arrowRight,
                    color: Colors.white,
                  ),
                ),
              )
            ],
          ),
        ),
      ],
    );
  }

  _countryChange(CountryCode countryCode) {
    setState(() {
      dialCode = countryCode.dialCode;
    });
  }

  _next() async {
    String phoneNumber = phonenumberCtl.text;
    if (phoneNumber.length < 5) {
      showMsgDialog(context, "Error", "Invalid phone number");
      return;
    }

    try {
      Exception exp;
      phoneNumber = phoneNumber[0] == "0"
          ? phoneNumber.replaceFirst("0", "")
          : phoneNumber;
      phoneNumber = dialCode + phoneNumber;

      await Navigator.push(
          context,
          MaterialPageRoute(
              builder: (context) => CodePage(phoneNumber: phoneNumber)));
      Navigator.pop(context);
      
      if (exp != null) throw exp;
    } catch (e) {
      showMsgDialog(context, "Error", e.toString());
    }
  }
}