在SQLite数据库混乱中搜索 [英] Searching in SQLite Database flutter

问题描述

如何使用TextField小部件作为搜索栏来查询本地SQLite数据库资产的结果?

How do I use a TextField widget as a search bar to query results from a local SQLite database asset?

有没有比使用文本框小部件更好的选择? 例子将不胜感激.

Would there be a better option than using a textfield widget? Examples would be much appreciated.

使用代码进行

 padding: EdgeInsets.all(10.0),
        child: Column(
          children: <Widget>[
            Container(
              padding: const EdgeInsets.all(8.0),
              child: new Container(
                  height: 70.0,
                  color: Theme.CompanyColors.iBlue,
                  child: new Padding(
                    padding: const EdgeInsets.all(8.0),
                    child: new Card(
                      child: new Container(
                        child: new Row(
                          mainAxisAlignment: MainAxisAlignment.spaceBetween,
                          children: <Widget>[
                            new Icon(Icons.search),
                            new Container(
                              width: MediaQuery.of(context).size.width - 100.0,
                              child: new TextField(
                                decoration: InputDecoration(
                                  hintText: 'Search',
                                  //onChanged:
                                  //onSearchTextChanged,
                                ),
                              ),
                            ),

这是搜索栏的代码

我的数据库中有一个表的句子，后面有一个段落ID，所以我想通过这样的查询进行搜索

my database has a table sentences attached with a paragraph_id, so i would want to search through a query like this

select * from sentences where title or body = userinput%

推荐答案

假设您使用的是此插件.您应该创建并填充数据库(插件的文档).

Assuming you're using this plugin. You should create and fill the database (plugin's docs).

然后，在搜索小部件中，使用以下示例:

Then, in the search widget, use below example:

class _MyHomePageState extends State<MyHomePage> {
  Database database;

  @override
  void initState() {
    // open the database
    openDatabase('pathToDb', version: 1,
        onCreate: (Database db, int version) async {
      database = db;
      // When creating the db, create the table

    });

    super.initState();
  }

  @override
  Widget build(BuildContext context) {
    if (database == null) {
      return CircularProgressIndicator();
    }
    return Container(
        padding: EdgeInsets.all(10.0),
        child: Column(children: <Widget>[
          Container(
              padding: const EdgeInsets.all(8.0),
              child: new Container(
                  height: 70.0,
                  child: new Padding(
                      padding: const EdgeInsets.all(8.0),
                      child: new Card(
                          child: new Container(
                              child: new Row(
                                  mainAxisAlignment:
                                      MainAxisAlignment.spaceBetween,
                                  children: <Widget>[
                            new Icon(Icons.search),
                            new Container(
                              width: MediaQuery.of(context).size.width - 100.0,
                              child: new TextField(
                                  decoration: InputDecoration(
                                    hintText: 'Search',
                                    //onSearchTextChanged,
                                  ),
                                  onChanged: (String text) async {
                                    List<Map> res = await database.rawQuery(
                                        "SELECT * FROM sentences WHERE title LIKE '%${text}%' OR  body LIKE '%${text}%'");
                                    print(res);
                                  }),
                            )
                          ]))))))
        ]));
  }
}

注意:如果多个窗口小部件可以访问数据库，请使用SQL帮助器.阅读文档"SQL帮助程序"部分.这个例子只是您的例子.

NOTE: If multiple widgets have access to DB, use SQL helpers. read the documents, section "SQL helpers". this example is just for your example.

这篇关于在SQLite数据库混乱中搜索的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！