view_note.dart

import 'package:flutter/material.dart';
import 'package:stream_post/data/blocs/bloc_provider.dart';
import 'package:stream_post/data/blocs/view_note_bloc.dart';
import 'package:stream_post/models/note_model.dart';

class ViewNotePage extends StatefulWidget {
    ViewNotePage({
        Key key,
        this.note
    }) : super(key: key);

    final Note note;

    @override
    _ViewNotePageState createState() => _ViewNotePageState();
}

class _ViewNotePageState extends State<ViewNotePage> {
    ViewNoteBloc _viewNoteBloc;
    TextEditingController _noteController = new TextEditingController();

    @override
    void initState() {
        super.initState();

        _viewNoteBloc = BlocProvider.of<ViewNoteBloc>(context);
        _noteController.text = widget.note.contents;
    }

    void _saveNote() async {
        widget.note.contents = _noteController.text;

        // Add the updated note to the save note stream. This triggers the function
        // we set in the listener.
        _viewNoteBloc.inSaveNote.add(widget.note);
    }

    void _deleteNote() {
        // Add the note id to the delete note stream. This triggers the function
        // we set in the listener.
        _viewNoteBloc.inDeleteNote.add(widget.note.id);

        // Wait for `deleted` to be set before popping back to the main page. This guarantees there's no
        // mismatch between what's stored in the database and what's being displayed on the page.
        // This is usually only an issue with more database heavy actions, but it's a good thing to
        // add regardless.
        _viewNoteBloc.deleted.listen((deleted) {
            if (deleted) {
                // Pop and return true to let the main page know that a note was deleted and that
                // it has to update the note stream.
                Navigator.of(context).pop(true);
            }
        });
    }

    @override
    Widget build(BuildContext context) {
        return Scaffold(
            appBar: AppBar(
                title: Text('Note ' + widget.note.id.toString()),
                actions: <Widget>[
                    IconButton(
                        icon: Icon(Icons.save),
                        onPressed: _saveNote,
                    ),
                    IconButton(
                        icon: Icon(Icons.delete),
                        onPressed: _deleteNote,
                    ),
                ],
            ),
            body: Container(
                child: TextField(
                    maxLines: null,
                    controller: _noteController,
                ),
            ),
        );
    }
}