sqlite - 在 Android 上后台获取 Flutter 访问数据库

Question

我试图在应用程序完全关闭时访问设备上的本地数据库，为此我使用了 sqlite 插件 sqflite: ^1.2.0和后台获取插件background_fetch: ^0.4.0 .

我可以毫无问题地注册 headless 后台任务，当我尝试运行后台任务时，出现以下错误!

当应用程序运行或进入后台模式时，插件似乎工作正常。

请问有什么建议吗？

错误

[ERROR:flutter/lib/ui/ui_dart_state.cc(157)] Unhandled Exception: MissingPluginException(No implementation found for method getDatabasesPath on channel com.tekartik.sqflite)

flutter 版本:

Flutter 1.12.13+hotfix.7 • channel stable • https://github.com/flutter/flutter.git
Framework • revision 9f5ff2306b (11 days ago) • 2020-01-26 22:38:26 -0800
Engine • revision a67792536c
Tools • Dart 2.7.0

flutter 医生

[✓] Flutter (Channel stable, v1.12.13+hotfix.7, on Mac OS X 10.15.2 19C57, locale en-GB)

[✓] Android toolchain - develop for Android devices (Android SDK version 28.0.3)
[✓] Xcode - develop for iOS and macOS (Xcode 11.3)
[✓] Android Studio (version 3.5)
[✓] Connected device (1 available)

• No issues found!

Answer 1

你可以试试看sqflite他们 Github 页面上的故障排除部分，尤其是 the one related to your error .让我把那个页面的内容粘贴到这里。

This error is typically a build/setup error after adding the dependency.

• Try all the steps defined at the top of the documents
• Make sure you stop the current running application if any
• Force a flutter packages get
• Try to clean your build folder flutter clean
• On iOS, you can try to force a pod install / pod update
• Search for other bugs in flutter like this, other people face the same issue with other plugins so it is likely not sqflite related

Advanced checks:

Check the GeneratedPluginRegistrant file that flutter run should have generated in your project contains a line registering the plugin.

安卓:

SqflitePlugin.registerWith(registry.registrarFor("com.tekartik.sqflite.SqflitePlugin"));

IOS:

[SqflitePlugin registerWithRegistrar:[registry registrarForPlugin:@"SqflitePlugin"]];

• Check MainActivity.java (Android) contains a call to GeneratedPluginRegistrant asking it to register itself. This call should be made from the app launch method (onCreate).

public class MainActivity extends FlutterActivity {
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        GeneratedPluginRegistrant.registerWith(this);
    }
}

• Check AppDelegate.m (iOS) contains a call to GeneratedPluginRegistrant asking it to register itself. This call should be made from the app launch method (application:didFinishLaunchingWithOptions:).

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {
  [GeneratedPluginRegistrant registerWithRegistry:self];
  return [super application:application didFinishLaunchingWithOptions:launchOptions];
}

Before raising this issue, try adding another well established plugin (the simplest being path_provider or shared_preferences) to see if you get the error here as well.