Center a Widget Inside a Column - user-interface

Question

I'm having an issue trying to align a text widget in the center of a column using flutter. Here's a screenshot of my UI so far, and I want to align the texts below "por Anúncio" in the center of the container. I tried using the Align Widget, another Column, a Center, but nothing worked so far.
Here is a screenshot of what I have:
And this is my code so far:
Container(
width: MediaQuery.of(context).size.width,
height: MediaQuery.of(context).size.height - 80,
decoration: new BoxDecoration(
gradient: LinearGradient(colors: [
index == 0
? Colors.lightGreen
: index == 1
? Colors.lightBlue
: index == 2 ? Colors.orangeAccent : Color(0xff2F4858),
index == 0
? Colors.green
: index == 1
? Colors.blueAccent
: index == 2 ? Colors.deepOrange : Color(0xff04030F)
], begin: Alignment.topLeft, end: Alignment.bottomRight),
borderRadius: BorderRadius.circular(15.0),
),
child: Column(
children: <Widget>[
Align(
alignment: Alignment.topRight,
child: Padding(
padding: const EdgeInsets.all(8.0),
child: GestureDetector(
onTap: () {
Navigator.of(context).pop();
},
child: Icon(
Icons.clear,
color: Colors.white,
)),
),
),
Text(
index == 0
? "Plano Pré Pago"
: index == 1
? "Plano Básico"
: index == 2 ? "Plano Intermediário" : "Plano Premium",
textAlign: TextAlign.center,
style: TextStyle(
color: Colors.white,
fontSize: 26,
fontWeight: FontWeight.bold,
decoration: TextDecoration.none),
),
Padding(
padding: const EdgeInsets.fromLTRB(5, 5, 5, 0),
child: Text(
index == 0
? "R\$ 19,90"
: index == 1
? "R\$ 19,90"
: index == 2 ? "R\$ 37,90" : "R\$ 99,00",
textAlign: TextAlign.center,
style: GoogleFonts.nanumGothic(
color: Colors.white,
fontSize: 60,
fontWeight: FontWeight.bold,
decoration: TextDecoration.none),
),
),
Padding(
padding: const EdgeInsets.fromLTRB(0, 5, 5, 0),
child: Text(
index == 0 ? "por Anúncio" : "Mensais",
textAlign: TextAlign.center,
style: GoogleFonts.nanumGothic(
color: Colors.white,
fontSize: 20,
fontWeight: FontWeight.bold,
decoration: TextDecoration.none),
),
),
Container(
child: Center(
child: Padding(
padding: const EdgeInsets.all(5.0),
child: Text(
"- 1 Anúncio Ativo\n- 1 Usuário\n- Notificação de interesses de compra\n- Válido para 30 dias",
textAlign: TextAlign.center,
style: GoogleFonts.nanumGothic(
color: Colors.white,
fontSize: 18,
fontWeight: FontWeight.w300,
decoration: TextDecoration.none),
),
),
),
),
],
),
);

Answer 1

You have to just add Expanded widget above and below You that Widget. Expanded widget will cover all possible hight so on both side you will get same space.
Expanded(
child : Container()
),
Container(
child: Center(
child: Padding(
padding: const EdgeInsets.all(5.0),
child: Text(
"- 1 Anúncio Ativo\n- 1 Usuário\n- Notificação de interesses de compra\n- Válido para 30 dias",
textAlign: TextAlign.center,
style: GoogleFonts.nanumGothic(
color: Colors.white,
fontSize: 18,
fontWeight: FontWeight.w300,
decoration: TextDecoration.none),
),
),
),
),
Expanded(
child : Container()
),