my_app_bar.dart 3.06 KB

import 'package:flutter/material.dart';
import 'package:flutter/services.dart';
import 'package:one_poem/util/theme_utils.dart';
import 'package:one_poem/res/resources.dart';

import 'my_button.dart';

/// 自定义AppBar
class MyAppBar extends StatelessWidget implements PreferredSizeWidget {

  const MyAppBar({
    Key? key,
    this.backgroundColor,
    this.title = '',
    this.centerTitle = '',
    this.actionName = '',
    this.backImg = 'assets/images/ic_back_black.png',
    this.backImgColor,
    this.onPressed,
    this.isBack = true
  }): super(key: key);

  final Color? backgroundColor;
  final String title;
  final String centerTitle;
  final String backImg;
  final Color? backImgColor;
  final String actionName;
  final VoidCallback? onPressed;
  final bool isBack;

  @override
  Widget build(BuildContext context) {
    final Color _backgroundColor = backgroundColor ?? context.backgroundColor;

    final SystemUiOverlayStyle _overlayStyle = ThemeData.estimateBrightnessForColor(_backgroundColor) == Brightness.dark
        ? SystemUiOverlayStyle.light : SystemUiOverlayStyle.dark;

    final Widget action = actionName.isNotEmpty ? Positioned(
      right: 0.0,
      child: Theme(
        data: Theme.of(context).copyWith(
          buttonTheme: const ButtonThemeData(
            padding: EdgeInsets.symmetric(horizontal: 16.0),
            minWidth: 60.0,
          ),
        ),
        child: MyButton(
          key: const Key('actionName'),
          fontSize: Dimens.font_sp14,
          minWidth: null,
          text: actionName,
          textColor: context.isDark ? Colours.dark_text : Colours.text,
          backgroundColor: Colors.transparent,
          onPressed: onPressed,
        ),
      ),
    ) : Gaps.empty;

    final Widget back = isBack ? IconButton(
      onPressed: () async {
        FocusManager.instance.primaryFocus?.unfocus();
        final isBack = await Navigator.maybePop(context);
        if (!isBack) {
          await SystemNavigator.pop();
        }
      },
      tooltip: 'Back',
      padding: const EdgeInsets.all(12.0),
      icon: Image.asset(
        backImg,
        color: backImgColor ?? ThemeUtils.getIconColor(context),
      ),
    ) : Gaps.empty;

    final Widget titleWidget = Semantics(
      namesRoute: true,
      header: true,
      child: Container(
        alignment: centerTitle.isEmpty ? Alignment.centerLeft : Alignment.center,
        width: double.infinity,
        margin: const EdgeInsets.symmetric(horizontal: 48.0),
        child: Text(
          title.isEmpty ? centerTitle : title,
          style: const TextStyle(fontSize: Dimens.font_sp18,),
        ),
      ),
    );
    
    return AnnotatedRegion<SystemUiOverlayStyle>(
      value: _overlayStyle,
      child: Material(
        color: _backgroundColor,
        child: SafeArea(
          child: Stack(
            alignment: Alignment.centerLeft,
            children: <Widget>[
              titleWidget,
              back,
              action,
            ],
          ),
        ),
      ),
    );
  }

  @override
  Size get preferredSize => const Size.fromHeight(48.0);
}