PlatformException(channel-error, Unable to establish connection on channel., null, null)

I tried to download document to local storage to Android, but got an error:

E/flutter ( 6441): [ERROR:flutter/lib/ui/ui_dart_state.cc(198)] Unhandled Exception: PlatformException(channel-error, Unable to establish connection on channel., null, null)
E/flutter ( 6441): #0      PathProviderApi.getApplicationDocumentsPath (package:path_provider_android/messages.g.dart:97:7)
E/flutter ( 6441): <asynchronous suspension>
E/flutter ( 6441): #1      getApplicationDocumentsDirectory (package:path_provider/path_provider.dart:115:24)
E/flutter ( 6441): <asynchronous suspension>
E/flutter ( 6441): #2      _FileContainerState.build.<anonymous closure>.<anonymous closure>
package:whatsapp_redesign/…/chat/file_container.dart:56
E/flutter ( 6441): <asynchronous suspension>

Here is the code:

  GestureDetector(
                  onTap: () async {
                    // chatBloc.add(SaveFileEvent(widget.message.file!));
                    final dir = await getApplicationDocumentsDirectory();
                    final file =
                        File('${dir.path}/${widget.message.file!.name}');
                    final ref = FirebaseStorage.instance
                        .ref('uploads/${widget.message.file!.name}');
                    await ref.writeToFile(file);
                  },

As I know, I need to get the local storage path and then save file from FireStorage Reference with writeToFile() method. But when I try to check if it works I get an error. Maybe I have to give some permission? I don't understand what is this error about :(

CodePudding user response：

Try to specify permissions if you are looking at a real android device.

<manifest xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
package="com.example.app">


<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />

<application

Inside android->app->src->main->AndroidManifest.xml