How to remove Padding from DrawerHeader

Question

Here's my DrawerHeader :

class MyDrawerHeader extends StatefulWidget {
  @override
  _MyDrawerHeaderState createState() => _MyDrawerHeaderState();
}

class _MyDrawerHeaderState extends State<MyDrawerHeader> {
  @override
  Widget build(BuildContext context) {
    return DrawerHeader(
      padding: EdgeInsets.all(0),
      margin: EdgeInsets.all(0),
      child: Center(child: Text('Header', style: Theme.of(context).textTheme.headline))
    );
  }
}

As you can see I made the Padding and Margin from the DrawerHeader be 0, but this is how my Header is being shown:

It's just too big and I can't make it smaller. I have no idea why its being rendered this way, I looked into DrawerHeader source code and I can't see anything in there overriding my Padding or Margin.

Just to be sure the problem is in DrawerHeader, this is what Happens when I substitute it for a Container:

It works as it should!

Am I missing something, or is this a bug in Flutter?

Answer 1

There is always padding on DrawerHeader. If you look in sources:

@override
Widget build(BuildContext context) {
  assert(debugCheckHasMaterial(context));
  assert(debugCheckHasMediaQuery(context));
  final ThemeData theme = Theme.of(context);
  final double statusBarHeight = MediaQuery.of(context).padding.top;
  return Container(
    height: statusBarHeight + _kDrawerHeaderHeight,
    margin: margin,
    decoration: BoxDecoration(
      border: Border(
        bottom: Divider.createBorderSide(context),
      ),
    ),
    child: AnimatedContainer(
      padding: padding.add(EdgeInsets.only(top: statusBarHeight)),
      decoration: decoration,
      duration: duration,
      curve: curve,
      child: child == null ? null : DefaultTextStyle(
        style: theme.textTheme.body2,
        child: MediaQuery.removePadding(
          context: context,
          removeTop: true,
          child: child,
        ),
      ),
    ),
  );
}

You can customize this code:

height: statusBarHeight + _kDrawerHeaderHeight - here is total height of header

padding: padding.add(EdgeInsets.only(top: statusBarHeight)) - here is padding of child element in DrawerHeader