sqflite_state_repository #

This package encapsulates Sqflite Table defined by RowModel, it encapsulats all the CRUD operations

Getting Started #

First we define the table Structure using Tabledef and Fieldefs

// It defines the table and fields that que repository creates // and manage CRUD operations // / // dart // table = TableDef(tableName: 'notes', fields: [ // FieldDef('id', DbType.integer, // primaryKey: true, // primaryKeyType: PrimaryKeyType.integer_auto_incremental), // FieldDef('title', DbType.text), // FieldDef('description', DbType.text), // FieldDef('priority', DbType.integer), // FieldDef('date', DbType.datetime) //

After we define the RowModel

Must create the props and implement

class Note extends RowModel{

  int get id => this['id'] ;
	String get title => this['title'];
  String get description => this['description'];
  int get priority => this['priority'];
  DateTime get date =>this['date'];

	set title(String newTitle) {
		if (newTitle.length <= 255) {
			this['title'] = newTitle;
		}
	}
  set description(String newDescription) {
		if (newDescription.length <= 255) {
			this['description'] = newDescription;
		}
	}
	set priority(int newPriority) {
		if (newPriority >= 1 && newPriority <= 2) {
			this['priority'] = newPriority;
		}
	}
	set date(DateTime newDate) {
		this['date'] = newDate;
	}

	Note(TableDef tableDef, [title, date, priority, description]) : super(tableDef)
  {
     if(!loaded())
      this.newRecord();
		this['title'] = title;
		this['description'] = description;
		this['priority'] = priority;
		this['date'] = date;   
  }
}

At last we inherit from SqfRepository

 class NoteRepository extends SqfRepository<Note> {
   NoteRepository() : super();

 Note addNew(String title, DateTime date, int priority, [String description]) {
   Note newNote = Note(this.table, title, date, priority, description);
   rows.add(newNote);
   this.current = newNote;
   return newNote;
 }


Define the table structure and when the class its instantiate, it creates the table

   @override
   getTableDefiniton() {
     table = TableDef(tableName: 'notes', fields: [
       FieldDef('id', DbType.integer,
           primaryKey: true,
           primaryKeyType: PrimaryKeyType.integer_auto_incremental),
       FieldDef('title', DbType.text),
       FieldDef('description', DbType.text),
       FieldDef('priority', DbType.integer),
       FieldDef('date', DbType.datetime)
     ]);
   }

   @override
   Note getNewRow() {
     return Note(table);
   }
 }

Then we can use in widgets and sign for change notifications Code for list

class NoteListState extends NotifiableState<NoteList> {
  NoteRepository noteRepo;
  @override
  void initState() {
    noteRepo = NoteRepository();
    noteRepo.addListener(this);
    super.initState();
  }

  @override
  Widget build(BuildContext context) {

    return Scaffold(
      appBar: AppBar(
        title: Text('Notes'),
      ),
      body: getNoteListView(),
      floatingActionButton: FloatingActionButton(
        onPressed: () {
          debugPrint('FAB clicked');
          noteRepo.addNew('',DateTime.now(),2);
          navigateToDetail('Add Note');
        },
        tooltip: 'Add Note',
        child: Icon(Icons.add),
      ),
    );
  }

  ListView getNoteListView() {
    TextStyle titleStyle = Theme.of(context).textTheme.subhead;
    
    return ListView.builder(
      itemCount: noteRepo.rows.length,
      itemBuilder: (BuildContext context, int position) {
        return Card(
          color: Colors.white,
          elevation: 2.0,
          child: ListTile(
            leading: CircleAvatar(
              backgroundColor:
                     getPriorityColor(noteRepo.rows[position]['priority']),
              child: getPriorityIcon(noteRepo.rows[position]['priority']),
            ),
            title: Text(
              //noteRepo.rows[position]['title'] work's this way either
              noteRepo.rows[position].title,
              style: titleStyle,
            ),
            subtitle: Text(DateFormat.yMMMMd().format(noteRepo.rows[position].date)),
            trailing: GestureDetector(
              child: Icon(
                Icons.delete,
                color: Colors.grey,
              ),
              onTap: () {
                _delete(context, noteRepo.rows[position]);
              },
            ),
            onTap: () {
              debugPrint("ListTile Tapped");
              noteRepo.setCurrent(noteRepo.rows[position]);
              navigateToDetail('Edit Note');
            },
          ),
        );
      },
    );
  }

  // Returns the priority color
  Color getPriorityColor(int priority) {
    switch (priority) {
      case 1:
        return Colors.red;
        break;
      case 2:
        return Colors.yellow;
        break;

      default:
        return Colors.yellow;
    }
  }

  // Returns the priority icon
  Icon getPriorityIcon(int priority) {
    switch (priority) {
      case 1:
        return Icon(Icons.play_arrow);
        break;
      case 2:
        return Icon(Icons.keyboard_arrow_right);
        break;

      default:
        return Icon(Icons.keyboard_arrow_right);
    }
  }

  void _delete(BuildContext context, Note note) async {
    int result = await noteRepo.delete(note);
    if (result == 1) {
      _showSnackBar(context, 'Note Deleted Successfully');
    }
  }

  void _showSnackBar(BuildContext context, String message) {
    final snackBar = SnackBar(content: Text(message));
    Scaffold.of(context).showSnackBar(snackBar);
  }

  void navigateToDetail(String title) async {
        await Navigator.push(context, MaterialPageRoute(builder: (context) {
      return NoteDetail(title);
    }));
  }

Code for detail

class NoteDetail extends StatefulWidget {

	final String appBarTitle;
	Note note;

	NoteDetail(this.appBarTitle);

	@override
  NotifiableState<StatefulWidget> createState() {

    return NoteDetailState(this.appBarTitle);
  }
}

class NoteDetailState extends NotifiableState<NoteDetail> {

	static var _priorities = ['High', 'Low'];

	String appBarTitle;
	Note note;

	TextEditingController titleController = TextEditingController();
	TextEditingController descriptionController = TextEditingController();

	NoteDetailState(this.appBarTitle);

@override
  void initState() {
    note = Repository.of<NoteRepository>().current;
    super.initState();
  }

	@override
  Widget build(BuildContext context) {

		TextStyle textStyle = Theme.of(context).textTheme.title;

		titleController.text = note.title;
		descriptionController.text = note.description;

    return WillPopScope(

	    onWillPop: () {
	    	// Write some code to control things, when user press Back navigation button in device navigationBar
		    moveToLastScreen();
	    },

	    child: Scaffold(
	    appBar: AppBar(
		    title: Text(appBarTitle),
		    leading: IconButton(icon: Icon(
				    Icons.arrow_back),
				    onPressed: () {
		    	    // Write some code to control things, when user press back button in AppBar
		    	    moveToLastScreen();
				    }
		    ),
	    ),

	    body: Padding(
		    padding: EdgeInsets.only(top: 15.0, left: 10.0, right: 10.0),
		    child: ListView(
			    children: <Widget>[

			    	// First element
				    ListTile(
					    title: DropdownButton(
							    items: _priorities.map((String dropDownStringItem) {
							    	return DropdownMenuItem<String> (
									    value: dropDownStringItem,
									    child: Text(dropDownStringItem),
								    );
							    }).toList(),

							    style: textStyle,

							    value: getPriorityAsString(note.priority),

							    onChanged: (valueSelectedByUser) {
							    	setState(() {
							    	  debugPrint('User selected $valueSelectedByUser');
							    	  updatePriorityAsInt(valueSelectedByUser);
							    	});
							    }
					    ),
				    ),

				    // Second Element
				    Padding(
					    padding: EdgeInsets.only(top: 15.0, bottom: 15.0),
					    child: TextField(
						    controller: titleController,
						    style: textStyle,
						    onChanged: (value) {
						    	debugPrint('Something changed in Title Text Field');
						    	updateTitle();
						    },
						    decoration: InputDecoration(
							    labelText: 'Title',
							    labelStyle: textStyle,
							    border: OutlineInputBorder(
								    borderRadius: BorderRadius.circular(5.0)
							    )
						    ),
					    ),
				    ),

				    // Third Element
				    Padding(
					    padding: EdgeInsets.only(top: 15.0, bottom: 15.0),
					    child: TextField(
						    controller: descriptionController,
						    style: textStyle,
						    onChanged: (value) {
							    debugPrint('Something changed in Description Text Field');
							    updateDescription();
						    },
						    decoration: InputDecoration(
								    labelText: 'Description',
								    labelStyle: textStyle,
								    border: OutlineInputBorder(
										    borderRadius: BorderRadius.circular(5.0)
								    )
						    ),
					    ),
				    ),

				    // Fourth Element
				    Padding(
					    padding: EdgeInsets.only(top: 15.0, bottom: 15.0),
					    child: Row(
						    children: <Widget>[
						    	Expanded(
								    child: RaisedButton(
									    color: Theme.of(context).primaryColorDark,
									    textColor: Theme.of(context).primaryColorLight,
									    child: Text(
										    'Save',
										    textScaleFactor: 1.5,
									    ),
									    onPressed: () {

									    	  debugPrint("Save button clicked");
									    	  _save();
									    },
								    ),
							    ),

							    Container(width: 5.0,),

							    Expanded(
								    child: RaisedButton(
									    color: Theme.of(context).primaryColorDark,
									    textColor: Theme.of(context).primaryColorLight,
									    child: Text(
										    'Delete',
										    textScaleFactor: 1.5,
									    ),
									    onPressed: () {
											    debugPrint("Delete button clicked");
											    _delete();
									    },
								    ),
							    ),

						    ],
					    ),
				    ),

			    ],
		    ),
	    ),

    ));
  }

  void moveToLastScreen() {
		Navigator.pop(context, true);
  }

	// Convert the String priority in the form of integer before saving it to Database
	void updatePriorityAsInt(String value) {
		switch (value) {
			case 'High':
				note.priority = 1;
				break;
			case 'Low':
				note.priority = 2;
				break;
		}
	}

	// Convert int priority to String priority and display it to user in DropDown
	String getPriorityAsString(int value) {
		String priority;
		switch (value) {
			case 1:
				priority = _priorities[0];  // 'High'
				break;
			case 2:
				priority = _priorities[1];  // 'Low'
				break;
		}
		return priority;
	}

	// Update the title of Note object
  void updateTitle(){
    note.title = titleController.text;
  }

	// Update the description of Note object
	void updateDescription() {
		note.description = descriptionController.text;
	}

	// Save data to database
	void _save() async {

		moveToLastScreen();

		note.date = DateTime.now();
		int result;
		if (note.id != null) {  // Case 1: Update operation
			result = await Repository.of<NoteRepository>().update(note);
		} else { // Case 2: Insert Operation
			result = await Repository.of<NoteRepository>().insert(note);
		}

		if (result != 0) {  // Success
			_showAlertDialog('Status', 'Note Saved Successfully');
		} else {  // Failure
			_showAlertDialog('Status', 'Problem Saving Note');
		}

	}

	void _delete() async {

		moveToLastScreen();

		// Case 1: If user is trying to delete the NEW NOTE i.e. he has come to
		// the detail page by pressing the FAB of NoteList page.
		if (note.id == null) {
			_showAlertDialog('Status', 'No Note was deleted');
			return;
		}

		// Case 2: User is trying to delete the old note that already has a valid ID.
		int result =await Repository.of<NoteRepository>().delete(note);
		if (result != 0) {
			_showAlertDialog('Status', 'Note Deleted Successfully');
		} else {
			_showAlertDialog('Status', 'Error Occured while Deleting Note');
		}
	}

	void _showAlertDialog(String title, String message) {

		AlertDialog alertDialog = AlertDialog(
			title: Text(title),
			content: Text(message),
		);
		showDialog(
				context: context,
				builder: (_) => alertDialog
		);
	}

}