Question

我想在listview中显示图像和文本。解析数据并将其设置在模型类中。能帮帮我吗以下是我的课程。

import 'dart:async';
import 'dart:convert';
import 'package:cached_network_image/cached_network_image.dart';
import 'package:flutter/foundation.dart';
import 'package:flutter/material.dart';
import 'package:flutter/services.dart';
import 'package:http/http.dart' as http;

Future<List<Photo>> fetchPhotos(http.Client client) async {
  final response = await client.get('url here');

  return compute(parsePhotos, response.body);
}

// A function that will convert a response body into a List<Photo>
List<Photo> parsePhotos(String responseBody) {
  final parsed = json.decode(responseBody);
  return (parsed["data"]["categoryList"] as List)
      .map<Photo>((json) => new Photo.fromJson(json))
      .toList();
}

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    // SystemChrome.setEnabledSystemUIOverlays([]);
    return new MyHomePage();
  }
}

class MyHomePage extends StatefulWidget {
  MyHomePage({Key key}) : super(key: key);

  @override
  _MyHomePageState createState() => new _MyHomePageState();
}

class _MyHomePageState extends State<MyHomePage> {
  @override
  Widget build(BuildContext context) {
    // TODO: implement build
    return new FutureBuilder<List<Photo>>(
      future: fetchPhotos(new http.Client()),
      builder: (context, snapshot) {
        if (snapshot.hasError) print(snapshot.error);
        return snapshot.hasData
            ? new PhotosList(photos: snapshot.data)
            : new Center(child: new CircularProgressIndicator());
      },
    );
  }
}

class PhotosList extends StatelessWidget {
  final List<Photo> photos;

  PhotosList({Key key, this.photos}) : super(key: key);

  @override
  Widget build(BuildContext context) {
    return new Column(
      mainAxisAlignment: MainAxisAlignment.center,
      mainAxisSize: MainAxisSize.max,
      children: <Widget>[
        new Expanded(child: _buildList(context)
        ),
    **//Able to display images but want to show text from list on images.**
        new Padding(
          padding: EdgeInsets.symmetric(horizontal: 16.0, vertical: 8.0),
          child: new Text('DAILY WALLPAPER',
              style: new TextStyle(
                  fontSize: 30.0,
                  color: Colors.black,
                  fontWeight: FontWeight.bold)),
        ),
      ],
    );
  }

  //Showing the images in listview
  ListView _buildList(context) {
    return new ListView.builder(
        itemCount: photos.length,
        itemBuilder: (context, int) {
          return new CachedNetworkImage(imageUrl: photos[int].url);
        });
  }
}

class Photo {
  final int catID;
  final String title;
  final String url;
  final String thumbnailUrl;
  final String description;
  final String webstiteURL;

  Photo(
      {this.catID,
      this.title,
      this.url,
      this.thumbnailUrl,
      this.description,
      this.webstiteURL});

  factory Photo.fromJson(Map<String, dynamic> json) {
    return new Photo(
      catID: json['category_id'] as int,
      title: json['category_name'] as String,
      url: json['category_img'] as String,
      thumbnailUrl: json['thumb_img'] as String,
      description: json['description'] as String,
      webstiteURL: json['website_url'] as String,
    );
  }
}

Answer 1

您需要在itemBuilder ListView属性中构建布局。如果要将文本放在图像上，最佳布局窗口小部件为Stack。

请参阅以下内容以获得颤振的布局系统： https://flutter.io/tutorials/layout/

并且对于所有可用的布局小部件，请参阅： https://flutter.io/widgets/layout/

和Stack： https://docs.flutter.io/flutter/widgets/Stack-class.html

这样的事情：

new Stack(
  children: <Widget>[
    new Positioned.fill(
      child: new FadeInImage(
        placeholder: new AssetImage('placeholder.png'),
        image: new CachedNetworkImageProvider(photos[int].url),
        fit: BoxFit.contain,
        alignment: Alignment.center,
        fadeInDuration: new Duration(milliseconds: 200),
        fadeInCurve: Curves.linear,
      ),
    ),
    new Positioned(
      top: 10.0,
      left: 10.0,
      child: new Container(
        child: new Text(photos[int].title)
      ),
    ),
  ],
)

如何在listview中显示图像和文本？

1 个答案: