前言

接续上 2 篇所需要的元件～～。

今日的程序码 => GITHUB

来补充前面两篇所需要的元件。

设定图片档案

https://github.com/wayne900204/Flutter-IT30/tree/main/day_25/images

CateGory Section

/// 每一个 Category Section 的样子。
class CategorySection extends StatelessWidget {
  TextTheme _textTheme(context) => Theme.of(context).textTheme;

  const CategorySection({
    Key? key,
    required this.category,
  }) : super(key: key);

  final Category category;

  @override
  Widget build(BuildContext context) {
    return Container(
      padding: const EdgeInsets.symmetric(horizontal: 16.0),
      margin: const EdgeInsets.only(bottom: 16),
      color: scheme.surface,
      child: Column(
        crossAxisAlignment: CrossAxisAlignment.start,
        children: [
          _buildSectionTileHeader(context),
          _buildFoodTileList(context),
        ],
      ),
    );
  }

  /// Section Title
  Widget _buildFoodTileList(BuildContext context) {
    return Column(
      children: List.generate(
        category.foods.length,
        (index) {
          final food = category.foods[index];
          bool isLastIndex = index == category.foods.length - 1;
          return _buildFoodTile(
            food: food,
            context: context,
            isLastIndex: isLastIndex,
          );
        },
      ),
    );
  }

  /// FSection Header
  Widget _buildSectionTileHeader(BuildContext context) {
    return Column(
      crossAxisAlignment: CrossAxisAlignment.start,
      children: [
        const SizedBox(height: 16),
        _sectionTitle(context),
        const SizedBox(height: 8.0),
        category.subtitle != null
            ? _sectionSubtitle(context)
            : const SizedBox(),
        const SizedBox(height: 16),
      ],
    );
  }

  /// Section Title 的 title
  Widget _sectionTitle(BuildContext context) {
    return Row(
      children: [
        if (category.isHotSale) _buildSectionHotSaleIcon(),
        Text(
          category.title,
          style: _textTheme(context).headline6,
          strutStyle: Helper.buildStrutStyle(_textTheme(context).headline6),
          // strutStyle: Helper.buildStrutStyle(_textTheme(context).headline6),
        )
      ],
    );
  }

  /// section Title 的 subTitle
  Widget _sectionSubtitle(BuildContext context) {
    return Text(
      category.subtitle!,
      style: _textTheme(context).subtitle2,
      strutStyle: Helper.buildStrutStyle(_textTheme(context).subtitle2),
    );
  }

  /// Section body 的 Food 样式。
  Widget _buildFoodTile({
    required BuildContext context,
    required bool isLastIndex,
    required Food food,
  }) {
    return Column(
      children: [
        Row(
          mainAxisAlignment: MainAxisAlignment.spaceBetween,
          children: [
            _buildFoodDetail(food: food, context: context),
            _buildFoodImage(food.imageUrl),
          ],
        ),
        !isLastIndex ? const Divider(height: 16.0) : const SizedBox(height: 8.0)
      ],
    );
  }

  /// food Image
  Widget _buildFoodImage(String url) {
    return FadeInImage.assetNetwork(
      placeholder: 'images/transparent.png',
      image: url,
      width: 64,
    );
  }

  /// food Detail
  Widget _buildFoodDetail({
    required BuildContext context,
    required Food food,
  }) {
    return Column(
      crossAxisAlignment: CrossAxisAlignment.start,
      children: [
        Text(food.name, style: _textTheme(context).subtitle1),
        const SizedBox(height: 16),
        Row(
          children: [
            Text(
              "特价" + food.price + " ",
              style: _textTheme(context).caption,
              strutStyle: Helper.buildStrutStyle(_textTheme(context).caption),
            ),
            Text(
              food.comparePrice,
              strutStyle: Helper.buildStrutStyle(_textTheme(context).caption),
              style: _textTheme(context)
                  .caption
                  ?.copyWith(decoration: TextDecoration.lineThrough),
            ),
            const SizedBox(width: 8.0),
            if (food.isHotSale) _buildFoodHotSaleIcon(),
          ],
        ),
      ],
    );
  }

  /// Section HotSale Icon
  Widget _buildSectionHotSaleIcon() {
    return Container(
      margin: const EdgeInsets.only(right: 4.0),
      child: Icon(
        Icons.whatshot,
        color: scheme.primary,
        size: 20.0,
      ),
    );
  }

  /// Food HotSale Icon
  Widget _buildFoodHotSaleIcon() {
    return Container(
      child: Icon(Icons.whatshot, color: scheme.primary, size: 16.0),
      padding: const EdgeInsets.all(4.0),
      decoration: BoxDecoration(
        color: scheme.primary.withOpacity(0.1),
        borderRadius: BorderRadius.circular(16.0),
      ),
    );
  }
}

客制化图片形状

/// 餐厅的图片形状
class CustomShape extends CustomClipper<Path> {
  @override
  getClip(Size size) {
    double height = size.height;
    double width = size.width;
    var path = Path();
    path.lineTo(0, height - 30);
    path.quadraticBezierTo(width / 2, height, width, height - 30);
    path.lineTo(width, 0);
    path.close();
    return path;
  }

  @override
  bool shouldReclip(CustomClipper oldClipper) => true;
}

折扣的 Card

/// 折扣卡片
class DiscountCard extends StatelessWidget {
  const DiscountCard({
    Key? key,
    required this.title,
    required this.subtitle,
  }) : super(key: key);

  final String title;
  final String subtitle;

  @override
  Widget build(BuildContext context) {
    var textTheme = Theme.of(context).textTheme;
    return Container(
      width: double.infinity,
      margin: const EdgeInsets.symmetric(
        horizontal: 16.0,
        vertical: 16.0,
      ),
      padding: const EdgeInsets.symmetric(
        horizontal: 16.0,
        vertical: 20,
      ),
      decoration: BoxDecoration(
        color: scheme.primary,
        borderRadius: BorderRadius.circular(10.0),
        image: DecorationImage(
          fit: BoxFit.cover,
          colorFilter: ColorFilter.mode(
            scheme.primary.withOpacity(0.08),
            BlendMode.dstATop,
          ),
          image: AssetImage('images/pattern.png'),
        ),
      ),
      child: Column(
        crossAxisAlignment: CrossAxisAlignment.start,
        children: [
          Text(
            title,
            style: textTheme.subtitle1
                ?.copyWith(color: scheme.surface, fontWeight: FontWeight.w600),
          ),
          Text(
            subtitle,
            style: textTheme.bodyText2?.copyWith(
              color: scheme.surface,
            ),
          ),
        ],
      ),
    );
  }
}

FIconButton

/// AppBar 的按钮
class FIconButton extends StatelessWidget {
  const FIconButton({
    Key? key,
    required this.iconData,
    required this.onPressed,
  }) : super(key: key);

  final IconData iconData;
  final void Function() onPressed;

  @override
  Widget build(BuildContext context) {
    return Center(
      child: IconButton(
        splashColor: Colors.transparent,
        onPressed: ()=>onPressed,
        icon: Container(
          height: 48,
          width: 48,
          decoration: buildBoxDecoration(),
          child: Icon(
            iconData,
            color: scheme.primary,
            size: 20,
          ),
        ),
      ),
    );
  }

  BoxDecoration buildBoxDecoration() {
    return BoxDecoration(
      shape: BoxShape.circle,
      color: scheme.surface,
    );
  }
}

FlutterHead

class FlutterHead extends StatelessWidget {
  const FlutterHead({
    Key? key,
  }) : super(key: key);

  final imageUrl =
      'https://flutter.dev/assets/images/shared/brand/flutter/logo/flutter-lockup.png';

  @override
  Widget build(BuildContext context) {
    return Positioned(
      bottom: -5,
      right: 10.0,
      child: FadeInImage.assetNetwork(
        placeholder: 'images/transparent.png',
        image: imageUrl,
        width: 150,
        height: 72,
        fit: BoxFit.fitWidth,
      ),
    );
  }
}

HeaderClip

/// App 餐厅图片的地方
class HeaderClip extends StatelessWidget {
  const HeaderClip({
    Key? key,
    required this.data,
    required this.context,
  }) : super(key: key);

  final PageData data;
  final BuildContext context;

  @override
  Widget build(BuildContext _) {
    final textTheme = Theme.of(context).textTheme;
    return ClipPath(
      clipper: CustomShape(),
      child: Stack(
        children: [
          Container(
            height: 275,
            color: scheme.primary.withOpacity(0.3),
            child: FadeInImage.assetNetwork(
              placeholder: 'images/transparent.png',
              image: data.backgroundUrl,
              width: double.infinity,
              fit: BoxFit.fitWidth,
            ),
          ),
          // 目的 让颜色变暗。
          Container(
            height: 275,
            color: scheme.secondary.withOpacity(0.7),
          ),
          Padding(
            padding: EdgeInsets.only(
              top: MediaQuery.of(context).viewPadding.top + kToolbarHeight,
            ),
            child: Column(
              children: [
                Text(
                  data.title,
                  style: textTheme.headline5?.copyWith(
                    color: scheme.surface,
                    fontWeight: FontWeight.w600,
                  ),
                  textAlign: TextAlign.center,
                ),
                const SizedBox(height: 8.0),
                Center(
                  child: Container(
                    padding: const EdgeInsets.symmetric(
                      horizontal: 16.0,
                      vertical: 4.0,
                    ),
                    decoration: BoxDecoration(
                      border: Border.all(color: scheme.surface),
                      borderRadius: BorderRadius.circular(50),
                    ),
                    child: Text(
                      "抵达时间: " + data.deliverTime,
                      style: textTheme.caption?.copyWith(color: scheme.surface),
                      strutStyle: StrutStyle(forceStrutHeight: true),
                    ),
                  ),
                ),
                const SizedBox(height: 8.0),
                Row(
                  mainAxisAlignment: MainAxisAlignment.center,
                  children: [
                    Icon(
                      Icons.star_rate_rounded,
                      size: 16,
                      color: scheme.surface,
                    ),
                    const SizedBox(width: 4.0),
                    Text(
                      data.rate.toString(),
                      style: textTheme.caption?.copyWith(
                        fontWeight: FontWeight.bold,
                        color: scheme.surface,
                      ),
                    ),
                    const SizedBox(width: 4.0),
                    Text(
                      "(" + data.rateQuantity.toString() + ")",
                      style: textTheme.caption?.copyWith(
                        color: scheme.surface,
                      ),
                    ),
                  ],
                )
              ],
            ),
          )
        ],
      ),
    );
  }
}

PromoText

/// 宣传框
class PromoText extends StatelessWidget {
  const PromoText({
    Key? key,
    required this.title,
  }) : super(key: key);

  final String title;
  @override
  Widget build(BuildContext context) {
    var textTheme = Theme.of(context).textTheme;
    // 这边是距离上一层的 Stack 的 bottom left right
    return Positioned(
      bottom: 0,
      left: 0,
      right: 0,
      child: Container(
        padding: const EdgeInsets.symmetric(
          horizontal: 16.0,
          vertical: 48,
        ),
        width: double.infinity,
        color: scheme.primary.withOpacity(0.1),
        child: Text(
          title,
          style: textTheme.bodyText1?.copyWith(color: scheme.primary),
        ),
      ),
    );
  }
}