Flutter Responsive Button With Icon and Text

responsive_icon_button.txt

/*
I tried so many Widgets to make Buttons with icons and text, but none worked for me, 
as it should be responsive. 
They used to crash with  different pixel size devices. 
Maybe someone will need this code or  if someone knows better option, 
write in comments please. because i need it.
Thank you.:)
*/

Flexible(
                      flex: 1,
                      fit: FlexFit.tight,
                      child: FlatButton(
                        shape: new RoundedRectangleBorder(
                          borderRadius: new BorderRadius.circular(5.0),
                        ),
                        color: Color.fromRGBO(58, 90, 128, 1),
                        child: Flex(
                         direction: Axis.horizontal,
                          textDirection: TextDirection.ltr,
                          children: <Widget>[
                             Flexible(flex: 10, child: Container()),
                            Flexible(flex: 10, child: Icon(Icons.email,color: Colors.white,)),
                            Flexible(flex: 1, child: Container()),
                            Flexible(flex: 20, fit: FlexFit.tight ,child: Text('Login by email', 
                            style: TextStyle(color: Colors.white,
                            ),
                              ),
                            ),
                          ],
                        ),
                        onPressed: () {
                          Navigator.push(
                              context,
                              MaterialPageRoute(
                                builder: (context) => GoToSomePage(),
                              ));
                        },
                      ),
                    ),