blob: 62ff66a571cd6891d144d046efaa4a1e8cc43de1 [file] [log] [blame]
// Copyright 2014 The Flutter Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
import 'package:flutter/widgets.dart';
import 'debug.dart';
import 'divider.dart';
import 'theme.dart';
const double _kDrawerHeaderHeight = 160.0 + 1.0; // bottom edge
/// The top-most region of a material design drawer. The header's [child]
/// widget, if any, is placed inside a [Container] whose [decoration] can be
/// passed as an argument, inset by the given [padding].
///
/// Part of the material design [Drawer].
///
/// Requires one of its ancestors to be a [Material] widget. This condition is
/// satisfied by putting the [DrawerHeader] in a [Drawer].
///
/// See also:
///
/// * [UserAccountsDrawerHeader], a variant of [DrawerHeader] that is
/// specialized for showing user accounts.
/// * <https://material.io/design/components/navigation-drawer.html>
class DrawerHeader extends StatelessWidget {
/// Creates a material design drawer header.
///
/// Requires one of its ancestors to be a [Material] widget.
const DrawerHeader({
Key key,
this.decoration,
this.margin = const EdgeInsets.only(bottom: 8.0),
this.padding = const EdgeInsets.fromLTRB(16.0, 16.0, 16.0, 8.0),
this.duration = const Duration(milliseconds: 250),
this.curve = Curves.fastOutSlowIn,
@required this.child,
}) : super(key: key);
/// Decoration for the main drawer header [Container]; useful for applying
/// backgrounds.
///
/// This decoration will extend under the system status bar.
///
/// If this is changed, it will be animated according to [duration] and [curve].
final Decoration decoration;
/// The padding by which to inset [child].
///
/// The [DrawerHeader] additionally offsets the child by the height of the
/// system status bar.
///
/// If the child is null, the padding has no effect.
final EdgeInsetsGeometry padding;
/// The margin around the drawer header.
final EdgeInsetsGeometry margin;
/// The duration for animations of the [decoration].
final Duration duration;
/// The curve for animations of the [decoration].
final Curve curve;
/// A widget to be placed inside the drawer header, inset by the [padding].
///
/// This widget will be sized to the size of the header. To position the child
/// precisely, consider using an [Align] or [Center] widget.
///
/// {@macro flutter.widgets.child}
final Widget child;
@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.bodyText1,
child: MediaQuery.removePadding(
context: context,
removeTop: true,
child: child,
),
),
),
);
}
}