Блог

Я новичок в Flutter и в программировании.

Я создал ListView с несколькими карточками внутри каждой карточки, чтобы разделить PDF-документы, которые загружаются с помощью пакета ‘advance_pdf_viewer’. Я сделал все это жестко. Но я хотел бы динамически генерировать карточки и PDF-документ. Как я могу это сделать?

Вот мои существующие коды:

Файл Main.dart:

 import 'package:flutter/material.dart';
import 'package:url_launcher/url_launcher.dart';
import 'package:font_awesome_flutter/font_awesome_flutter.dart';

import 'c9Bban.dart';
import 'c9Bbanbakoron.dart';

void main() => runApp(MyApp());

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      debugShowCheckedModeBanner: false,
      title: 'HSC Textbooks',
      theme: ThemeData(
        primarySwatch: Colors.cyan,
      ),
      home: MyHomePage(),
    );
  }
}

class MyHomePage extends StatefulWidget {
  @override
  _MyHomePageState createState() => _MyHomePageState();
}

class _MyHomePageState extends State<MyHomePage> {
  
  @override
  void initState() {
    super.initState();
  }

  @override
  Widget build(BuildContext context) {
  
    return Scaffold(
      appBar: AppBar(
        title: Text(
          '১ম - ১০ম শ্রেণী পাঠ্যবই',
          style: TextStyle(
            //fontSize: 14,
            fontFamily: 'Baloo Da',
          ),
        ),
        centerTitle: true,
      ),
      body: ListView(children: [
        Card(
          child: Row(children: <Widget>[
            Expanded(
              flex: 8, // 20%
              child: Container(
                child: ListTile(
                  leading: ConstrainedBox(
                    constraints: BoxConstraints(
                      maxWidth: 44,
                      maxHeight: 44,
                    ),
                    child: Image.asset('images/bangla bakaron.jpg',
                        fit: BoxFit.cover),
                  ),
                  title: Text(
                    'বাংলা ব্যাকরণ',
                    style: TextStyle(
                      fontSize: 16,
                      fontWeight: FontWeight.bold,
                      fontFamily: 'Baloo da',
                    ),
                  ),
                  subtitle: Text(
                    'জাতীয় শিক্ষাক্রম ও পাঠ্যপুস্তক বোর্ড',
                    style: TextStyle(
                      fontSize: 12,
                      fontFamily: 'Baloo da',
                    ),
                  ),
                ),
              ),
            ),
            Expanded(
              flex: 4, // 20%
              child: GestureDetector(
                onTap: () {
                  Navigator.push(context,
                      MaterialPageRoute(builder: (context) => C9Bbanbakoron()));
                },
                child: Container(
                  decoration: BoxDecoration(
                      border: Border.all(color: Colors.grey[300])),
                  child: Column(
                    mainAxisAlignment: MainAxisAlignment.center,
                    crossAxisAlignment: CrossAxisAlignment.center,
                    children: [
                      Icon(FontAwesomeIcons.book, color: Colors.green),
                      SizedBox(height: 5),
                      Text('বাংলা ও ইংরেজি ভার্সন',
                          textAlign: TextAlign.center,
                          style: TextStyle(
                            fontSize: 14,
                          )),
                    ],
                  ),
                ),
              ),
            ),
          ]),
        ),
        Card(
          child: Row(children: <Widget>[
            Expanded(
              flex: 8, // 20%
              child: Container(
                child: ListTile(
                  leading: ConstrainedBox(
                    constraints: BoxConstraints(
                      maxWidth: 44,
                      maxHeight: 44,
                    ),
                    child: Image.asset('images/BGS.jpg', fit: BoxFit.cover),
                  ),
                  title: Text(
                    'বাংলাদেশ ও বিশ্বপরিচয়',
                    style: TextStyle(
                      fontSize: 16,
                      fontWeight: FontWeight.bold,
                      fontFamily: 'Baloo da',
                    ),
                  ),
                  subtitle: Text(
                    'জাতীয় শিক্ষাক্রম ও পাঠ্যপুস্তক বোর্ড',
                    style: TextStyle(
                      fontSize: 12,
                      fontFamily: 'Baloo da',
                    ),
                  ),
                ),
              ),
            ),
            Expanded(
              flex: 2, // 20%
              child: GestureDetector(
                onTap: () {
                  Navigator.push(context,
                      MaterialPageRoute(builder: (context) => C9Bbgs()));
                },
                child: Container(
                  decoration: BoxDecoration(
                      border: Border.all(color: Colors.grey[300])
                  ),
                  child: Column(
                    mainAxisAlignment: MainAxisAlignment.center,
                    crossAxisAlignment: CrossAxisAlignment.center,
                    children: [
                      Icon(FontAwesomeIcons.book, color: Colors.green),
                      SizedBox(height: 5),
                      Text('বাংলা ভার্সন',
                          textAlign: TextAlign.center,
                          style: TextStyle(
                            fontSize: 14,
                          )
                      ),
                    ],
                  ),
                ),
              ),
            ),
            Expanded(
              flex: 2, // 20%
              child: GestureDetector(
                onTap: () {
                  Navigator.push(context,
                      MaterialPageRoute(builder: (context) => C9Ebgs()));
                },
                child: Container(
                  decoration: BoxDecoration(
                      border: Border.all(color: Colors.grey[300])
                  ),
                  child: Column(
                    mainAxisAlignment: MainAxisAlignment.center,
                    crossAxisAlignment: CrossAxisAlignment.center,
                    children: [
                      Icon(FontAwesomeIcons.book, color: Colors.green),
                      SizedBox(height: 5),
                      Text('ইংরেজি ভার্সন',
                          textAlign: TextAlign.center,
                          style: TextStyle(
                            fontSize: 14,
                          )
                      ),
                    ],
                  ),
                ),
              ),
            ),
          ]),
        ),
      ]),
    );
  }
}
 

Файл c9Bban.dart (один из отдельных файлов для загрузки отдельных PDF-документов. Остальные файлы точно такие же, за исключением того, что URL-адрес PDF отличается):

 import 'package:flutter/material.dart';
import 'package:advance_pdf_viewer/advance_pdf_viewer.dart';

class C9Bban extends StatefulWidget {
  @override
  _MyC9Bban createState() => _MyC9Bban();
}

class _MyC9Bban extends State<C9Bban> {
  bool _isLoading = true;
  PDFDocument document;

  @override
  void initState() {
    super.initState();
    loadDocument();
  }

  loadDocument() async {
    document = await PDFDocument.fromURL('https://storage.googleapis.com/school_books/Class9/ban/Bangla Sahitto.pdf');

    setState(() => _isLoading = false);
  }
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      home: Scaffold(
        appBar: AppBar(
          toolbarHeight: 20,
        ),
        body: Center(
          child: _isLoading
              ? Center(child: CircularProgressIndicator())
              : PDFViewer(
            document: document,
            zoomSteps: 1,
          ),
        ),
        bottomNavigationBar: BottomAppBar(
          child: Container(
            height: 85.0,
          ),
        ),
      ),
    );
  }
}
 

До сих пор я смог создать это, которое работает для динамического создания карточек ListView.

 import 'package:flutter/material.dart';
import 'package:font_awesome_flutter/font_awesome_flutter.dart';
import 'package:advance_pdf_viewer/advance_pdf_viewer.dart';

import 'c9Bban.dart';
import 'c9Bbansohopath.dart';

void main() => runApp(MyApp());

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      debugShowCheckedModeBanner: false,
      title: 'HSC Textbooks',
      theme: ThemeData(
        primarySwatch: Colors.cyan,
      ),
      home: MyHomePage(),
    );
  }
}

class MyHomePage extends StatefulWidget {
  @override
  _MyHomePageState createState() => _MyHomePageState();
}

class _MyHomePageState extends State<MyHomePage> {

  @override
  Widget build(BuildContext context) {
    List booklist = [
      Books(
        image: 'Bangla.jpg',
        bookname: 'Bangla',
        banbookname: 'C9Bban',
      ),
      Books(
        image: 'bangla shapath.jpg',
        bookname: 'Bangla Sahapath',
        banbookname: 'C9Bbansohopath',
      ),
    ];

    void updateBook(index) {
      Navigator.push(context, MaterialPageRoute(builder: (context) => booklist[index].banbookname));
    }

    return Scaffold(
      appBar: AppBar(
        title: Text('Book App'),
        centerTitle: true,
      ),
      body: ListView.builder(
          itemCount: booklist.length,
          itemBuilder: (context, index) {
            return Card(
              child: Row(children: <Widget>[
                Expanded(
                  flex: 8, // 20%
                  child: Container(
                    child: ListTile(
                      leading: ConstrainedBox(
                        constraints: BoxConstraints(
                          maxWidth: 44,
                          maxHeight: 44,
                        ),
                        child:
                            Image.asset('images/islam.jpg', fit: BoxFit.cover),
                      ),
                      title: Text(
                        booklist[index].bookname,
                        style: TextStyle(
                          fontSize: 16,
                          fontWeight: FontWeight.bold,
                          fontFamily: 'Baloo da',
                        ),
                      ),
                      subtitle: Text(
                        'জাতীয় শিক্ষাক্রম ও পাঠ্যপুস্তক বোর্ড',
                        style: TextStyle(
                          fontSize: 12,
                          fontFamily: 'Baloo da',
                        ),
                      ),
                    ),
                  ),
                ),
                Expanded(
                  flex: 2, // 20%
                  child: GestureDetector(
                    onTap: () {
                      updateBook(index);
                    },
                    child: Container(
                      decoration: BoxDecoration(
                          border: Border.all(color: Colors.grey[300])),
                      child: Column(
                        mainAxisAlignment: MainAxisAlignment.center,
                        crossAxisAlignment: CrossAxisAlignment.center,
                        children: [
                          Icon(FontAwesomeIcons.book, color: Colors.green),
                          SizedBox(height: 5),
                          Text('বাংলা ভার্সন',
                              textAlign: TextAlign.center,
                              style: TextStyle(
                                fontSize: 14,
                              )),
                        ],
                      ),
                    ),
                  ),
                ),
                Expanded(
                  flex: 2, // 20%
                  child: GestureDetector(
                    onTap: () {
                      updateBook(index);
                    },
                    child: Container(
                      decoration: BoxDecoration(
                          border: Border.all(color: Colors.grey[300])),
                      child: Column(
                        mainAxisAlignment: MainAxisAlignment.center,
                        crossAxisAlignment: CrossAxisAlignment.center,
                        children: [
                          Icon(FontAwesomeIcons.book, color: Colors.green),
                          SizedBox(height: 5),
                          Text('ইংরেজি ভার্সন',
                              textAlign: TextAlign.center,
                              style: TextStyle(
                                fontSize: 14,
                              )),
                        ],
                      ),
                    ),
                  ),
                ),
              ]),
            );
          }),
    );
  }
}

class Books {
  String image;
  String bookname;
  String banbookname;
  String engbook;

  Books({this.image, this.bookname, this.banbookname});
}