How to display images from a external storage path in flutter?

Question

Im basically new to flutter. I want to display Images from specific path like "Storage/WhatsApp/Media/". I want to show all the images in grid view. How can i acheive this in flutter. I have seen many examples but everyone is using assets folder. This is the code for getting the path. How to display them in grid view?

 Future<String> get localpath async
 {
  final dir=await getExternalStorageDirectory();
  return dir.path;
 }

 Future<File> get localfile async{
 final path=await localpath;
 return File('$path/WhatsApp/Media/WhatsApp Images');
}

Future<String> readData() async{
try{
  final file=await localfile;
  String image_path=await file.readAsString();
  return image_path;
}
catch(e) {return e.toString();}
}

Now since i got the path how to display images in gridview? Should i use gridview.builder?

Solution 1

Provide your storage path and you can display image

Image.file(File(imagePath);

Solution 2

I've tried following a similar approach as yours for fetching files by using path_provider. However, the plugin is only able to fetch the app's directory, even when using getExternalStorageDirectory(). This behavior is also pointed out in this Stack Overflow post.

Instead, I've used ext_storage to access the device's storage.

This sample app demonstrates fetching files on your device's /Download folder using ext_storage, handling permissions using permission_handler, file extension check, and displaying images from path on a GridView.

import 'dart:io';

import 'package:flutter/material.dart';
import 'package:ext_storage/ext_storage.dart';
import 'package:permission_handler/permission_handler.dart';

void main() {
  runApp(MyApp());
}

class MyApp extends StatelessWidget {
  // This widget is the root of your application.
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Flutter Demo',
      theme: ThemeData(
        primarySwatch: Colors.blue,
        visualDensity: VisualDensity.adaptivePlatformDensity,
      ),
      home: MyHomePage(title: 'Flutter Demo Home Page'),
    );
  }
}

class MyHomePage extends StatefulWidget {
  MyHomePage({Key key, this.title}) : super(key: key);

  final String title;

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

class _MyHomePageState extends State<MyHomePage> {
  Future _futureGetPath;
  List<dynamic> listImagePath = List<dynamic>();
  var _permissionStatus;

  @override
  void initState() {
    super.initState();
    _listenForPermissionStatus();
    // Declaring Future object inside initState() method
    // prevents multiple calls inside stateful widget
    _futureGetPath = _getPath();
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text(widget.title),
      ),
      body: Column(
        mainAxisAlignment: MainAxisAlignment.spaceEvenly,
        children: <Widget>[
          Expanded(
            flex: 1,
            child: FutureBuilder(
              future: _futureGetPath,
              builder: (BuildContext context, AsyncSnapshot snapshot) {
                if (snapshot.hasData) {
                  var dir = Directory(snapshot.data);
                  print('permission status: $_permissionStatus');
                  if (_permissionStatus) _fetchFiles(dir);
                  return Text(snapshot.data);
                } else {
                  return Text("Loading");
                }
              },
            ),
          ),
          Expanded(
            flex: 19,
            child: GridView.count(
              primary: false,
              padding: const EdgeInsets.all(20),
              crossAxisSpacing: 10,
              mainAxisSpacing: 10,
              crossAxisCount: 3,
              children: _getListImg(listImagePath),
            ),
          )
        ],
      ),
    );
  }

  // Check for storage permission
  void _listenForPermissionStatus() async {
    final status = await Permission.storage.request().isGranted;
    // setState() triggers build again
    setState(() => _permissionStatus = status);
  }

  // Get storage path
  // https://pub.dev/documentation/ext_storage/latest/
  Future<String> _getPath() {
    return ExtStorage.getExternalStoragePublicDirectory(
        ExtStorage.DIRECTORY_DOWNLOADS);
  }

  _fetchFiles(Directory dir) {
    List<dynamic> listImage = List<dynamic>();
    dir.list().forEach((element) {
      RegExp regExp =
      new RegExp("\.(gif|jpe?g|tiff?|png|webp|bmp)", caseSensitive: false);
      // Only add in List if path is an image
      if (regExp.hasMatch('$element')) listImage.add(element);
      setState(() {
        listImagePath = listImage;
      });
    });
  }

  List<Widget> _getListImg(List<dynamic> listImagePath) {
    List<Widget> listImages = List<Widget>();
    for (var imagePath in listImagePath) {
      listImages.add(
        Container(
          padding: const EdgeInsets.all(8),
          child: Image.file(imagePath, fit: BoxFit.cover),
        ),
      );
    }
    return listImages;
  }
}

Note that this only covers the basics of displaying images on a GridView. To scale, I suggest following this guide on performance best practices.

Comments

[Oswin Noetzelmann]

You are on the right path. Make sure to check out the FileImage class and using Gridview.builder should work fine. See this blog.

[Admin]

Yeah I got it. But suppose the directory has 10 images like 'WA001.JPG,WA004.JPG'. Should I create an array list and send it to FileImage?

[Oswin Noetzelmann]

No, the Gridview.builder uses the list to build 10 FileImages inside the itembuilder property - compare the example on the blog I linked.