Question

In my app I do want to save some data with sqflite plugin, but it keeps throwing me the error:

    Unhandled exception: type '_InternalLinkedHashMap' is not a subtype of type 
Map<String, dynamic>' where _InternalLinkedHashMap is from dart:collection 

     - Map is from dart:core
     - String is from dart:core

This is my code for regenerating my error:

Rezepte.dart The where I am handling the table named Rezepte from the database.

class Rezepte{
  Rezepte();

  int id;
  String name;
  int personen;
  String beschreibung;
  int favorit;

  static final spalten = ["id", "name", "personen", "beschreibung", "favorit"];

  Map toMap(){
    Map map = {
      "name": name,
      "personen": personen,
      "beschreibung": beschreibung,
      "favorit":favorit
    };

    if(id != null){
      map["id"] = id;
    }

    return map;
  }


  static fromMap(Map map){
    Rezepte rezepte = new Rezepte();
    rezepte.id = map["id"];
    rezepte.name = map["name"];
    rezepte.personen = map["personen"];
    rezepte.beschreibung = map["beschreibung"];
    rezepte.favorit = map["favorit"];

    return rezepte;
  }

}

Datenbank.dart The code for handling the whole database. My Database-H

import 'dart:async';
import 'dart:io';
import 'package:flutter_app/datenbank/Rezepte.dart';
import 'package:path/path.dart';
import 'package:sqflite/sqflite.dart';
import 'package:path_provider/path_provider.dart';

class DatabaseClient{
  Database database;

  //Datenbank wird erstellt
  Future erstellen() async{
    Directory pfad = await getApplicationDocumentsDirectory();
    String datenbankPfad = join(pfad.path, "rezept_buch.db");

    database = await openDatabase(datenbankPfad, version: 1, onCreate: this.erstelleTabellen);
  }

  //Die Tabellen werden erstellt
  Future erstelleTabellen(Database db, int version) async{
    await db.execute("""
      create table rezept (
        id integer primary key,
        name text not null,
        personen_anzahl integer not null,
        beschreibung text default null,
        favorit integer default 0
      )
    """);
  }


  Future setRezept(Rezepte rezepte) async{
    var count = Sqflite.firstIntValue(await database.rawQuery("SELECT * FROM rezept WHERE name =?", [rezepte.name]));
    if(count == 0){
      rezepte.id = await database.insert("rezept", rezepte.toMap());
    } else {
      await database.update("rezept", rezepte.toMap(), where: "id = ?", whereArgs: [rezepte.id]);
    }

    return rezepte;
  }

  //Daten aus Tabellen holen
  Future getAllRezepte(int id) async{
    List ergebnisse = await database.query("rezept", columns: Rezepte.spalten, where: "id=?", whereArgs: [id]);
    Rezepte rezepte = Rezepte.fromMap(ergebnisse[0]);

    return rezepte;
  }
}

This two files are the only one, that are able to generate my error. Does anybody have an idea how I could possibly solve the error?

Answer 1

Hard to know where the issue happens without a longer stack trace. Make sure you are using the latest version (sqflite >=8.4) especially if you are using --preview-dart-2. I also recommend turning on implicit-casts: false in analysis_options.yaml

analyzer:
  strong-mode:
    implicit-casts: false

Casting a Map to Map<String, dynamic> could throw an error if the map is not of the proper type. The crash reported by Flutter should also indicate the file and line where the issue happened.

Flutter SQflite: How to solve unhandled exception?

1 个答案: