flutter-sport/lib/db/step_db.dart

import 'dart:async';

import 'package:path/path.dart';
import 'package:sport/provider/bluetooth.dart';
import 'package:sqflite/sqflite.dart';

class StepDB {
  static final StepDB _instance = new StepDB.internal();

  factory StepDB() => _instance;

  static Database _db;

  StepDB.internal();

  Future<Database> get db async {
    if (_db != null) {
      return _db;
    }
    _db = await initDb();

    return _db;
  }

  final String TABLE = 'step';

  initDb() async {
    String databasesPath = await getDatabasesPath();
    String path = join(databasesPath, 'step.db');

    var db = await openDatabase(path, version: 1, onCreate: _onCreate);
    return db;
  }

  FutureOr<void> _onCreate(Database db, int version) async {
    await db.execute('CREATE TABLE $TABLE(id INTEGER PRIMARY KEY, step INTEGER, distance INTEGER, time INTEGER)');
  }

  Future<int> insert(PartItem item) async {
    var dbClient = await db;
    var result = await dbClient.insert(TABLE, item.toJson());
    return result;
  }

  Future insertAll(List<PartItem> items) async {
    var dbClient = await db;
    var batch = dbClient.batch();
    items.forEach((item) {
      batch.insert(TABLE, item.toJson());
    });
    batch.commit();
  }

  Future<List<Map<String, dynamic>>> find() async {
    var dbClient = await db;
    return await dbClient.rawQuery('SELECT SUM(step) as st, SUM(distance) as di, time FROM $TABLE GROUP BY time ORDER BY time LIMIT 1000');
  }

  Future<int> delete(int time) async {
    var dbClient = await db;
    return await dbClient.delete(TABLE, where: "time <= ?", whereArgs: [time]);
  }
}