feature: Added month and day view

- Added month view
- Added day view
- Added example to demonstrate month view and day view.

example/.gitignore

@@ -46,3 +46,4 @@ app.*.map.json
 /android/app/release
 
 pubspec.lock
+.vscode/

example/lib/constants.dart

@@ -0,0 +1,8 @@
+import 'dart:ui';
+
+class AppConstants {
+  AppConstants._();
+
+  static const Color black = Color(0xff444444);
+  static const Color white = Color(0xffefefef);
+}

example/lib/create_event_page.dart

@@ -0,0 +1,209 @@
+import 'package:example/constants.dart';
+import 'package:example/date_time_selector.dart';
+import 'package:example/event.dart';
+import 'package:flutter/cupertino.dart';
+import 'package:flutter/material.dart';
+import 'package:flutter_calendar_page/flutter_calendar_page.dart';
+
+import 'extension.dart';
+
+class CreateEventPage extends StatefulWidget {
+  final bool withDuration;
+
+  const CreateEventPage({Key? key, this.withDuration = false})
+      : super(key: key);
+
+  @override
+  _CreateEventPageState createState() => _CreateEventPageState();
+}
+
+class _CreateEventPageState extends State<CreateEventPage> {
+  GlobalKey<FormState> _formKey = GlobalKey();
+
+  late DateTime _date;
+  DateTime? _startTime;
+  DateTime? _endTime;
+  String _title = "";
+  String _description = "";
+
+  late FocusNode _titleNode;
+  late FocusNode _descriptionNode;
+  late FocusNode _dateNode;
+
+  @override
+  void initState() {
+    super.initState();
+
+    _titleNode = FocusNode();
+    _descriptionNode = FocusNode();
+    _dateNode = FocusNode();
+  }
+
+  @override
+  void dispose() {
+    _titleNode.dispose();
+    _descriptionNode.dispose();
+    _dateNode.dispose();
+
+    super.dispose();
+  }
+
+  @override
+  Widget build(BuildContext context) {
+    return Scaffold(
+      appBar: AppBar(
+        elevation: 0,
+        backgroundColor: Theme.of(context).scaffoldBackgroundColor,
+        centerTitle: false,
+        leading: IconButton(
+          onPressed: context.popRoute,
+          icon: Icon(
+            Icons.arrow_back,
+            color: AppConstants.black,
+          ),
+        ),
+        title: Text(
+          "Create New Event",
+          style: TextStyle(
+            color: AppConstants.black,
+            fontSize: 20.0,
+            fontWeight: FontWeight.bold,
+          ),
+        ),
+      ),
+      body: Form(
+        key: _formKey,
+        child: ListView(
+          padding: const EdgeInsets.symmetric(vertical: 30.0, horizontal: 10.0),
+          shrinkWrap: true,
+          scrollDirection: Axis.vertical,
+          children: [
+            TextFormField(
+              focusNode: _titleNode,
+              style: TextStyle(
+                color: AppConstants.black,
+                fontSize: 17.0,
+              ),
+              decoration: InputDecoration(
+                labelText: "Title",
+              ),
+              textInputAction: TextInputAction.next,
+              validator: (value) {
+                if (value == null || value.trim() == "") return "Invalid Title";
+                return null;
+              },
+              onSaved: (value) => _title = value ?? "",
+            ),
+            SizedBox(
+              height: 15.0,
+            ),
+            DateTimeSelectorFormField(
+              decoration: InputDecoration(
+                labelText: "Select Date",
+              ),
+              onSave: (date) => _date = date,
+              textStyle: TextStyle(
+                color: AppConstants.black,
+                fontSize: 17.0,
+              ),
+              type: DateTimeSelectionType.date,
+            ),
+            SizedBox(
+              height: 15.0,
+            ),
+            if (widget.withDuration) ...[
+              Row(
+                mainAxisSize: MainAxisSize.max,
+                children: [
+                  Expanded(
+                    child: DateTimeSelectorFormField(
+                      decoration: InputDecoration(
+                        labelText: "Start Time",
+                      ),
+                      textStyle: TextStyle(
+                        color: AppConstants.black,
+                        fontSize: 17.0,
+                      ),
+                      onSave: (date) => _startTime = date,
+                      type: DateTimeSelectionType.time,
+                    ),
+                  ),
+                  SizedBox(width: 20.0),
+                  Expanded(
+                    child: DateTimeSelectorFormField(
+                      decoration: InputDecoration(
+                        labelText: "End Time",
+                      ),
+                      textStyle: TextStyle(
+                        color: AppConstants.black,
+                        fontSize: 17.0,
+                      ),
+                      onSave: (date) => _endTime = date,
+                      type: DateTimeSelectionType.time,
+                    ),
+                  ),
+                ],
+              ),
+              SizedBox(
+                height: 15.0,
+              ),
+            ],
+            TextFormField(
+              focusNode: _descriptionNode,
+              style: TextStyle(
+                color: AppConstants.black,
+                fontSize: 17.0,
+              ),
+              keyboardType: TextInputType.multiline,
+              textInputAction: TextInputAction.newline,
+              selectionControls: MaterialTextSelectionControls(),
+              minLines: 1,
+              maxLines: 10,
+              maxLength: 1000,
+              validator: (value) {
+                if (value == null || value.trim() == "")
+                  return "Invalid Description";
+                return null;
+              },
+              decoration: InputDecoration(
+                labelText: "Description",
+              ),
+              onSaved: (value) => _description = value ?? "",
+            ),
+            SizedBox(
+              height: 50.0,
+            ),
+            ElevatedButton(
+              onPressed: () {
+                if (_formKey.currentState?.validate() ?? false) {
+                  _formKey.currentState?.save();
+                  CalendarEventData<Event> event = CalendarEventData<Event>(
+                    date: _date,
+                    event: Event(title: _title),
+                    title: _title,
+                    description: _description,
+                    startTime: _startTime,
+                    endTime: _endTime,
+                  );
+                  context.popRoute(event);
+                }
+              },
+              child: Text(
+                "Create",
+                style: Theme.of(context)
+                    .textTheme
+                    .subtitle1!
+                    .copyWith(color: AppConstants.white),
+              ),
+              style: ButtonStyle(
+                elevation: MaterialStateProperty.all<double>(8),
+                padding: MaterialStateProperty.all<EdgeInsets>(
+                    EdgeInsets.symmetric(vertical: 10.0)),
+              ),
+            ),
+          ],
+        ),
+      ),
+    );
+  }
+}

example/lib/date_time_selector.dart

@@ -0,0 +1,147 @@
+import 'package:flutter/material.dart';
+import 'package:flutter_calendar_page/flutter_calendar_page.dart';
+
+import 'extension.dart';
+
+typedef Validator = String? Function(String? value);
+
+enum DateTimeSelectionType { date, time }
+
+class DateTimeSelectorFormField extends StatefulWidget {
+  final Function(DateTime?)? onSelect;
+  final DateTimeSelectionType? type;
+  final FocusNode? focusNode;
+  final DateTime? minimumDateTime;
+  final Validator? validator;
+  final bool displayDefault;
+  final TextStyle? textStyle;
+  final void Function(DateTime date)? onSave;
+  final InputDecoration? decoration;
+
+  const DateTimeSelectorFormField({
+    this.onSelect,
+    this.type,
+    this.onSave,
+    this.decoration,
+    this.focusNode,
+    this.minimumDateTime,
+    this.validator,
+    this.displayDefault = false,
+    this.textStyle,
+  });
+
+  @override
+  _DateTimeSelectorFormFieldState createState() =>
+      _DateTimeSelectorFormFieldState();
+}
+
+class _DateTimeSelectorFormFieldState extends State<DateTimeSelectorFormField> {
+  late TextEditingController _textEditingController;
+  late FocusNode _focusNode;
+
+  late DateTime _selectedDate;
+
+  @override
+  void initState() {
+    super.initState();
+
+    _textEditingController = TextEditingController();
+    _focusNode = FocusNode();
+
+    _selectedDate = widget.minimumDateTime ?? DateTime.now();
+
+    if (widget.displayDefault && widget.minimumDateTime != null) {
+      if (widget.type == DateTimeSelectionType.date) {
+        _textEditingController.text = widget.minimumDateTime
+                ?.dateToStringWithFormat(format: "dd/MM/yyyy") ??
+            "";
+      } else {
+        _textEditingController.text =
+            widget.minimumDateTime?.getTimeInFormat(TimeStampFormat.parse_12) ??
+                "";
+      }
+    }
+  }
+
+  @override
+  void dispose() {
+    _focusNode.dispose();
+    _textEditingController.dispose();
+    super.dispose();
+  }
+
+  Future<void> _showSelector() async {
+    DateTime? date;
+
+    if (widget.type == DateTimeSelectionType.date) {
+      date = await _showDateSelector();
+      _textEditingController.text =
+          (date ?? _selectedDate).dateToStringWithFormat(format: "dd/MM/yyyy");
+    } else {
+      date = await _showTimeSelector();
+      _textEditingController.text =
+          (date ?? _selectedDate).getTimeInFormat(TimeStampFormat.parse_12);
+    }
+
+    _selectedDate = date ?? DateTime.now();
+
+    if (mounted) {
+      setState(() {});
+    }
+
+    widget.onSelect?.call(date);
+  }
+
+  Future<DateTime?> _showDateSelector() async {
+    DateTime now = widget.minimumDateTime ?? DateTime.now();
+
+    DateTime? date = await showDatePicker(
+      context: context,
+      initialDate: now,
+      firstDate: widget.minimumDateTime ?? now,
+      lastDate: Constants.maxDate,
+    );
+
+    if (date == null) return null;
+
+    return date;
+  }
+
+  Future<DateTime?> _showTimeSelector() async {
+    DateTime now = widget.minimumDateTime ?? DateTime.now();
+    TimeOfDay? time = await showTimePicker(
+      context: context,
+      builder: (context, widget) {
+        return widget ?? Container();
+      },
+      initialTime: TimeOfDay(hour: now.hour, minute: now.minute),
+    );
+
+    if (time == null) return null;
+
+    DateTime? date = now.copyWith(
+      hour: time.hour,
+      minute: time.minute,
+    );
+
+    if (widget.minimumDateTime == null) return date;
+
+    return date;
+  }
+
+  @override
+  Widget build(BuildContext context) {
+    return GestureDetector(
+      onTap: _showSelector,
+      child: TextFormField(
+        style: widget.textStyle,
+        controller: _textEditingController,
+        validator: widget.validator,
+        minLines: 1,
+        onSaved: (value) => widget.onSave?.call(_selectedDate),
+        enabled: false,
+        decoration: widget.decoration,
+      ),
+    );
+  }
+}