Line 26 – 32 : We update the existing record of the student using the updateStudent() function. Line 24: We read a table named student using the getStudents() function. Line 21 – 22: We insert a student in our table named Student using the insert keyword.
If it exists, that instance will be returned.Line 11 – 18: We create and connect to a database named studentDB and create a table named Student. The database getter will check if there’s any previously created instance of the Database object. The DatabaseProvider class needs to be a singleton class, so we can create just one object of this class and use its state globally throughout the app whenever we want to use one of its methods. single reference to the database throughout the app Static final DatabaseProvider db = DatabaseProvider._() Next, add the following lines to your DatabaseProvider class: // make this a singleton class Instead of manually typing dream everytime we want to query on our dream table, we can simply use the TABLE_DREAM constant in its place. Hence, we created the 4 constants TABLE_DREAM, COLUMN_ID, COLUMN_TITLE and COLUMN_DETAILS to avoid typing errors when we write our database queries or perform serialisation/deserialisation in our Dream class. Our database will have one table called dream, and this table will have 3 fields namely id, title and details because these are the 3 fields that we want to record for every dream entry in our journal. Static const String COLUMN_DETAILS = 'details' Static const String COLUMN_TITLE = 'title' Static const String TABLE_DREAM = 'dream' Import 'package:sqflite/sqlite_api.dart' import 'models.dart' // the file that contains our Dream class This will contain our DatabaseProvider class – the class responsible for performing all operations related to our database. Let’s set these up next! Creating The Database Helper ClassĬreate a new file db_provider.dart. Simply put, toMap() will handle the serialisation of our Dream object, and fromMap() will handle the deserialisation.Īlso note the use of constants in place of each of the keys in our Map in the toMap() and fromMap() methods. The fromMap() method converts the Map object that we retrieve from the database into the actual Dream object which will then be displayed in its respective UI. The toMap() method converts our Dream object to a Map object, so it can be stored in our database, Title = map ĭetails = map Įach dream entry that we create for our journal will have a unique id, title and dream details that we want to record. / deserialise object when reading from database
/ serialise object when writing to databaseĭatabaseProvider.COLUMN_DETAILS: details, Next, create a simple Dream class with the attributes you want to record and store in the database: class Dream )
FLUTTER SQLITE UPGRADE
If you run into any errors relating to version conflicts while running flutter pub get, upgrade or downgrade the version of the plugin throwing this error to make it consistent with the current version of your flutter sdk. Path is the plugin responsible for physically embedding the database to the local disk. Sqflite is the Flutter plugin for SQLite and will be used to create/open our locally embedded database and perform CRUD operations on it, Getting Startedįirst off, add the following dependencies in your pubspec.yaml: dependencies: This tutorial will only focus on the aspects of SQFLite – to keep things simple. I’m using BLoC for State Management here, but it’s etirely up to you to use whichever state management technique you prefer, depending on your use case. Screen 3: a search screen to look up dream entries containing that specific keyword in their titles. Screen 2: a form for the journal entry used to either record a new dream or to view an existing dream and edit it. Screen 1: a list of all entries along with a floating action button to create a new journal entry, and each entry has a X button to delete that specific entry. Dream Journal app using SQFLite App ArchitectureĪs seen in the gif above, our Dream Journal app has a total of 3 screens:
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