Q: Horizontally centering Text widget inside Stack I need to center a Text widget inside a Stack widget.
This is my code for the Text widget:
 Positioned(
          top: alturaFondo + alturaAvatar/2,

          child:  Padding(
              padding: const EdgeInsets.all(8.0),
              child:
                  Text("username", textAlign: TextAlign.center, style: TextStyle(fontSize: 18,color: Colors.black54),)

              ),
            ),

I have tried putting the Text inside an Align widget, but not centering it either.

A: You can do it like this
Stack(
  children: [
    Positioned.fill(
      child: Center(
        child: Text('centered'),
      ),
    )
  ],
)


A: With Positioned(left:0,right:0) just horizontal-center
body: Stack(
  children: [
    Positioned(
      left: 0,
      right: 0,
      child: Text(
        "username",
        textAlign: TextAlign.center,
        style: TextStyle(fontSize: 18, color: Colors.black54),
      ),
    ),
  ],
),

You can use just Center
Stack(
  children: [
    Center(
      child: Text(
        "username",
        textAlign: TextAlign.center,
        style: TextStyle(fontSize: 18, color: Colors.black54),
      ),
    ),
  ],
),

with Aling widget,
Stack(
  children: [
    Align(
      alignment: Alignment.center,// default also center
      child: Text(
        "username",
        textAlign: TextAlign.center,
        style: TextStyle(fontSize: 18, color: Colors.black54),
      ),
    ),
  ],
),

