我有一个JSON，它是简单结构和复杂结构的组合。无论如何，您都可以看一下。我想要的就是获取“ playlist_url”：值并在列表视图构建器中显示它。解析我可以做的2个文本值。但是url部分是我无法解析的地方
JSON结构（太长了，这就是我给的链接）：https://docs.google.com/document/d/1saJN3MQvG55M1ipf42-65Etowi_kW80gkrosU6vBb5o/edit?usp=sharing
PODO文件：
// To parse this JSON data, do
//
// final homePage = homePageFromJson(jsonString);
import 'dart:convert';
HomePage homePageFromJson(String str) => HomePage.fromJson(json.decode(str));
String homePageToJson(HomePage data) => json.encode(data.toJson());
class HomePage {
HomePage({
this.series,
this.homeBanners,
this.liveChannels,
this.publishers,
this.musicCategories,
this.musicPlaylists,
this.movies,
});
List<HomeBanner> series;
List<HomeBanner> homeBanners;
List<LiveChannel> liveChannels;
List<Publisher> publishers;
List<Music> musicCategories;
Music musicPlaylists;
List<HomeBanner> movies;
factory HomePage.fromJson(Map<String, dynamic> json) => HomePage(
series: List<HomeBanner>.from(
json["series"].map((x) => HomeBanner.fromJson(x))),
homeBanners: List<HomeBanner>.from(
json["home_banners"].map((x) => HomeBanner.fromJson(x))),
liveChannels: List<LiveChannel>.from(
json["live_channels"].map((x) => LiveChannel.fromJson(x))),
publishers: List<Publisher>.from(
json["publishers"].map((x) => Publisher.fromJson(x))),
musicCategories: List<Music>.from(
json["music_categories"].map((x) => Music.fromJson(x))),
musicPlaylists: Music.fromJson(json["music_playlists"]),
movies: List<HomeBanner>.from(
json["movies"].map((x) => HomeBanner.fromJson(x))),
);
Map<String, dynamic> toJson() => {
"series": List<dynamic>.from(series.map((x) => x.toJson())),
"home_banners": List<dynamic>.from(homeBanners.map((x) => x.toJson())),
"live_channels":
List<dynamic>.from(liveChannels.map((x) => x.toJson())),
"publishers": List<dynamic>.from(publishers.map((x) => x.toJson())),
"music_categories":
List<dynamic>.from(musicCategories.map((x) => x.toJson())),
"music_playlists": musicPlaylists.toJson(),
"movies": List<dynamic>.from(movies.map((x) => x.toJson())),
};
}
class HomeBanner {
HomeBanner({
this.movieId,
this.title,
this.tags,
this.genres,
this.thumbnail,
this.posterLink,
this.platform,
this.worldwide,
this.createdAt,
this.seriesId,
});
String movieId;
String title;
List<String> tags;
List<String> genres;
List<String> thumbnail;
String posterLink;
Platform platform;
double worldwide;
DateTime createdAt;
String seriesId;
factory HomeBanner.fromJson(Map<String, dynamic> json) => HomeBanner(
movieId: json["movie_id"] == null ? null : json["movie_id"],
title: json["title"],
tags: List<String>.from(json["tags"].map((x) => x)),
genres: List<String>.from(json["genres"].map((x) => x)),
thumbnail: List<String>.from(json["thumbnail"].map((x) => x)),
posterLink: json["poster_link"],
platform: platformValues.map[json["platform"]],
worldwide: json["WORLDWIDE"],
createdAt: DateTime.parse(json["createdAt"]),
seriesId: json["series_id"] == null ? null : json["series_id"],
);
Map<String, dynamic> toJson() => {
"movie_id": movieId == null ? null : movieId,
"title": title,
"tags": List<dynamic>.from(tags.map((x) => x)),
"genres": List<dynamic>.from(genres.map((x) => x)),
"thumbnail": List<dynamic>.from(thumbnail.map((x) => x)),
"poster_link": posterLink,
"platform": platformValues.reverse[platform],
"WORLDWIDE": worldwide,
"createdAt": createdAt.toIso8601String(),
"series_id": seriesId == null ? null : seriesId,
};
}
enum Platform { YOUTUBE, DISCOVERYPLUS }
final platformValues = EnumValues(
{"discoveryplus": Platform.DISCOVERYPLUS, "youtube": Platform.YOUTUBE});
class LiveChannel {
LiveChannel({
this.keyId,
this.postContent,
this.publisherId,
this.publisherName,
this.publisherProfilePic,
this.publisherDesc,
this.downvotesCount,
this.upvotesCount,
});
String keyId;
PostContent postContent;
String publisherId;
String publisherName;
String publisherProfilePic;
String publisherDesc;
int downvotesCount;
int upvotesCount;
factory LiveChannel.fromJson(Map<String, dynamic> json) => LiveChannel(
keyId: json["key_id"],
postContent: PostContent.fromJson(json["post_content"]),
publisherId: json["publisher_id"],
publisherName: json["publisher_name"],
publisherProfilePic: json["publisher_profile_pic"],
publisherDesc: json["publisher_desc"],
downvotesCount: json["downvotes_count"],
upvotesCount: json["upvotes_count"],
);
Map<String, dynamic> toJson() => {
"key_id": keyId,
"post_content": postContent.toJson(),
"publisher_id": publisherId,
"publisher_name": publisherName,
"publisher_profile_pic": publisherProfilePic,
"publisher_desc": publisherDesc,
"downvotes_count": downvotesCount,
"upvotes_count": upvotesCount,
};
}
class PostContent {
PostContent({
this.shortcode,
this.platformVideoLink,
this.caption,
this.description,
});
String shortcode;
String platformVideoLink;
String caption;
String description;
factory PostContent.fromJson(Map<String, dynamic> json) => PostContent(
shortcode: json["shortcode"],
platformVideoLink: json["platform_videoLink"],
caption: json["caption"],
description: json["description"],
);
Map<String, dynamic> toJson() => {
"shortcode": shortcode,
"platform_videoLink": platformVideoLink,
"caption": caption,
"description": description,
};
}
class Music {
Music({
this.id,
this.country,
this.categoryId,
this.categoryName,
this.categoryIcons,
this.playlists,
});
dynamic id;
String country;
String categoryId;
String categoryName;
List<CategoryIcon> categoryIcons;
List<Playlist> playlists;
factory Music.fromJson(Map<String, dynamic> json) => Music(
id: json["_id"],
country: json["country"],
categoryId: json["category_id"],
categoryName: json["category_name"],
categoryIcons: List<CategoryIcon>.from(
json["category_icons"].map((x) => CategoryIcon.fromJson(x))),
playlists: List<Playlist>.from(
json["playlists"].map((x) => Playlist.fromJson(x))),
);
Map<String, dynamic> toJson() => {
"_id": id,
"country": country,
"category_id": categoryId,
"category_name": categoryName,
"category_icons":
List<dynamic>.from(categoryIcons.map((x) => x.toJson())),
"playlists": List<dynamic>.from(playlists.map((x) => x.toJson())),
};
}
class CategoryIcon {
CategoryIcon({
this.height,
this.url,
this.width,
});
int height;
String url;
int width;
factory CategoryIcon.fromJson(Map<String, dynamic> json) => CategoryIcon(
height: json["height"] == null ? null : json["height"],
url: json["url"],
width: json["width"] == null ? null : json["width"],
);
Map<String, dynamic> toJson() => {
"height": height == null ? null : height,
"url": url,
"width": width == null ? null : width,
};
}
class Playlist {
Playlist({
this.playlistName,
this.playlistDescription,
this.playlistUrl,
this.playlistTotalTracks,
this.playlistImages,
this.playlistFollowers,
this.playlistId,
});
String playlistName;
String playlistDescription;
String playlistUrl;
int playlistTotalTracks;
List<CategoryIcon> playlistImages;
int playlistFollowers;
String playlistId;
factory Playlist.fromJson(Map<String, dynamic> json) => Playlist(
playlistName: json["playlist_name"],
playlistDescription: json["playlist_description"],
playlistUrl: json["playlist_url"],
playlistTotalTracks: json["playlist_total_tracks"],
playlistImages: List<CategoryIcon>.from(
json["playlist_images"].map((x) => CategoryIcon.fromJson(x))),
playlistFollowers: json["playlist_followers"],
playlistId: json["playlist_id"],
);
Map<String, dynamic> toJson() => {
"playlist_name": playlistName,
"playlist_description": playlistDescription,
"playlist_url": playlistUrl,
"playlist_total_tracks": playlistTotalTracks,
"playlist_images":
List<dynamic>.from(playlistImages.map((x) => x.toJson())),
"playlist_followers": playlistFollowers,
"playlist_id": playlistId,
};
}
class Publisher {
Publisher({
this.platform,
this.username,
this.fullName,
this.profilePicUrl,
this.content,
this.keyId,
});
Platform platform;
String username;
String fullName;
String profilePicUrl;
Content content;
String keyId;
factory Publisher.fromJson(Map<String, dynamic> json) => Publisher(
platform: platformValues.map[json["platform"]],
username: json["username"],
fullName: json["full_name"],
profilePicUrl: json["profile_pic_url"],
content: Content.fromJson(json["content"]),
keyId: json["key_id"],
);
Map<String, dynamic> toJson() => {
"platform": platformValues.reverse[platform],
"username": username,
"full_name": fullName,
"profile_pic_url": profilePicUrl,
"content": content.toJson(),
"key_id": keyId,
};
}
class Content {
Content({
this.description,
});
String description;
factory Content.fromJson(Map<String, dynamic> json) => Content(
description: json["description"],
);
Map<String, dynamic> toJson() => {
"description": description,
};
}
class EnumValues<T> {
Map<String, T> map;
Map<T, String> reverseMap;
EnumValues(this.map);
Map<T, String> get reverse {
if (reverseMap == null) {
reverseMap = map.map((k, v) => new MapEntry(v, k));
}
return reverseMap;
}
}
我试图解析playlist_url的类叫做services。我能够解析播放列表名称和视频数量（计数）
class Services {
static const String url =
"https://livetvapi.apyhi.com/api/v2/home?pageLocation=home&countries=IN&app_version=13&"
"user_id=44edc2c905ae163f&package_id=livetv.movies.freemovies.watchtv.tvshows&os_platform=android";
static Future<List<String>> loadDataForPlaylistDetailsForButtomTitle() async {
var res = await http
.get(url, headers: {'Authorization': dartJsonWebTokenGenerator()});
if (res.statusCode == 200) {
print("response is there");
final homePage = homePageFromJson(res.body);
Playlist playListObject = new Playlist();
List<String> lst_names = [];
for (playListObject in homePage.musicPlaylists.playlists)
lst_names.add(playListObject.playlistName);
print("Buttom titles");
print(lst_names);
return lst_names;
} else {
print("no response");
return null;
}
}
static Future<List<String>> loadDataForPlaylistDetailsForCount() async {
var res = await http
.get(url, headers: {'Authorization': dartJsonWebTokenGenerator()});
if (res.statusCode == 200) {
print("response is there");
final homePage = homePageFromJson(res.body);
Playlist playListObject = new Playlist();
List<String> lst_names = [];
for (playListObject in homePage.musicPlaylists.playlists)
lst_names.add(playListObject.playlistTotalTracks.toString());
print("count");
print(lst_names);
return lst_names;
} else {
print("no response");
return null;
}
}
static Future<List<Playlist>> loadDataForPlaylistDetailsForImageUrl() async {
var res = await http
.get(url, headers: {'Authorization': dartJsonWebTokenGenerator()});
if (res.statusCode == 200) {
print("response is there");
final homePage = homePageFromJson(res.body);
Music musicObject = new Music();
List<Playlist> playlistObj = homePage.musicPlaylists.playlists;
print("category icon object returned");
return playlistObj;
} else {
print("no response");
return null;
}
}
}
这是我要在listView中显示的主文件。首先将数据加载到initstate中，然后存储在数组中。但是对于最后一个（URL内容），我尝试了对象本身的自定义复杂
@override
void initState() {
// TODO: implement initState
super.initState();
Services.loadDataForPlaylistDetailsForButtomTitle().then((playListNames) {
setState(() {
_playListNames = playListNames ;
});
});
Services.loadDataForPlaylistDetailsForButtomTitle().then((playListCount) {
setState(() {
_playListtotalTracks = playListCount ;
});
});
Services.loadDataForPlaylistDetailsForImageUrl().then((objUrl) {
setState(() {
_obj = objUrl ;
});
});
}
listView Builder的代码：
Container(
height: MediaQuery.of(context).size.height * 0.41,
color: Colors.black,
child: ListView.builder(
shrinkWrap: true,
scrollDirection: Axis.horizontal,
itemCount: _playListImageUrls.length,
itemBuilder: (BuildContext context, int index) => Column(
crossAxisAlignment: CrossAxisAlignment.start,
children: <Widget>[
Container(
margin: EdgeInsets.fromLTRB(10, 0, 10, 0),
height: MediaQuery.of(context).size.height * 0.34,
child: PhysicalModel(
clipBehavior: Clip.antiAliasWithSaveLayer,
color: Colors.black,
shape: BoxShape.rectangle,
borderRadius: BorderRadius.only(
topRight: Radius.circular(35),
bottomRight: Radius.circular(35)),
child: FadeInImage.assetNetwork(
width: MediaQuery.of(context).size.width * 0.285,
image: _obj[index].playlistImages[index].url,
placeholder: cupertinoActivityIndicator,
fit: BoxFit.fill,
),
),
),
Container(
margin: EdgeInsets.fromLTRB(15, 15, 0, 0),
height: MediaQuery.of(context).size.height * 0.03,
child: Text(
_playListNames[index],
style: TextStyle(color: Colors.white),
)),
Container(
margin: EdgeInsets.fromLTRB(15, 0, 0, 0),
height: MediaQuery.of(context).size.height * 0.02,
child: Text(
_playListtotalTracks[index],
style: TextStyle(color: Colors.white),
))
],
),
),
),
我也发现自己重复了很多次这种结构，任何即兴创作的建议也将受到欢迎。
答案 0 :(得分：1)
我终于找到了解决方案。我犯错的全部要点是将事物假定为对象列表，而不是单个对象列表的列表。
进行了以下修改：
在服务文件中
static Future<List<String>> loadDataForPlaylistDetailsForImageUrl() async {
var res = await http
.get(url, headers: {'Authorization': dartJsonWebTokenGenerator()});
if (res.statusCode == 200) {
print("response is thereeeeeeeee");
final homePage = homePageFromJson(res.body);
Playlist playListObject = new Playlist();
List<String> urlList = [];
List<dynamic> lst_names = [];
for (playListObject in homePage.musicPlaylists.playlists) {
lst_names.add(playListObject.playlistImages);
print(lst_names);
}
//lst_names=
print("objjjjjjjjjjjjjjjjjjjj");
for (var listobj in lst_names) {
for (var obj in listobj) {
print(obj.url.toString());
urlList.add(obj.url.toString());
}
}
return urlList;
} else {
print("no response");
return null;
}
}
也在主文件中：
FadeInImage.assetNetwork(
width: MediaQuery.of(context).size.width * 0.285,
image: _musicPlaylistImgUrlList[index],
//_categoryIconfor[index].url,
//_obj[index].playlistImages[index].url,
placeholder: cupertinoActivityIndicator,
fit: BoxFit.none,
),