Add datepicker widget

widget/datepicker.go

@@ -0,0 +1,212 @@
+// DatePicker is a widget for selecting a date. It consists of three dropdowns
+// for year, month, and day. The days dropdown is dynamically updated based
+// on the selected month and year.
+//
+// Usage:
+//
+//	dp := widgets.NewDatePicker()
+//	date, err := dp.GetDate()
+//	if err != nil {
+//	    log.Println("No date selected")
+//	} else {
+//	    log.Println("Selected date:", date)
+//	}
+
+package widget
+
+import (
+	"fmt"
+	"strconv"
+	"time"
+
+	"fyne.io/fyne/v2"
+)
+
+// DatePicker is a custom widget for selecting a date.
+type DatePicker struct {
+	BaseWidget
+	YearSelect  *Select
+	MonthSelect *Select
+	DaySelect   *Select
+}
+
+// NewDatePicker creates a new DatePicker widget.
+func NewDatePicker() *DatePicker {
+	dp := &DatePicker{}
+	dp.ExtendBaseWidget(dp)
+
+	// Generate lists of years and months
+	years := generateYears()
+	months := generateMonths()
+
+	// Get Current Time to use as placeholders
+	currentTime := time.Now()
+
+	// Extract the year, month, and day and convert them to strings
+	year := currentTime.Year()
+	month := currentTime.Month()
+	day := currentTime.Day()
+
+	// Convert year and day to strings
+	yearStr := strconv.Itoa(year)
+	dayStr := strconv.Itoa(day)
+
+	// Get the numeric value of the month (integer)
+	monthNum := int(month)
+
+	// Convert the month to a string
+	monthStr := strconv.Itoa(monthNum)
+
+	// Create Select widgets for years and months
+	dp.YearSelect = NewSelect(years, nil)
+	dp.YearSelect.PlaceHolder = yearStr
+
+	dp.MonthSelect = NewSelect(months, nil)
+	dp.MonthSelect.PlaceHolder = monthStr
+
+	dp.DaySelect = NewSelect([]string{}, nil) // Initialize with empty days
+	dp.DaySelect.PlaceHolder = dayStr
+
+	// Function to update the days based on the selected month and year
+	updateDays := func() {
+		selectedYear := dp.YearSelect.Selected
+		selectedMonth := dp.MonthSelect.Selected
+
+		if selectedYear == "" || selectedMonth == "" {
+			return // No selection yet
+		}
+
+		// Convert selected year and month to integers
+		year := 0
+		month := 0
+		fmt.Sscanf(selectedYear, "%d", &year)
+		fmt.Sscanf(selectedMonth, "%d", &month)
+
+		// Generate the list of days for the selected month and year
+		days := generateDays(month, year)
+
+		// Update the DaySelect widget
+		dp.DaySelect.Options = days
+		dp.DaySelect.Refresh()
+	}
+
+	// Set up callbacks for year and month selection
+	dp.YearSelect.OnChanged = func(_ string) {
+		updateDays()
+	}
+	dp.MonthSelect.OnChanged = func(_ string) {
+		updateDays()
+	}
+
+	return dp
+}
+
+// CreateRenderer implements fyne.Widget.
+func (dp *DatePicker) CreateRenderer() fyne.WidgetRenderer {
+	return &datePickerRenderer{
+		dp: dp,
+	}
+}
+
+// datePickerRenderer is the renderer for the DatePicker widget.
+type datePickerRenderer struct {
+	dp *DatePicker
+}
+
+// Layout implements fyne.WidgetRenderer.
+func (r *datePickerRenderer) Layout(size fyne.Size) {
+	// Define the layout for the YearSelect, MonthSelect, and DaySelect widgets
+	yearWidth := size.Width / 3
+	monthWidth := size.Width / 3
+	dayWidth := size.Width / 3
+
+	r.dp.YearSelect.Resize(fyne.NewSize(yearWidth, size.Height))
+	r.dp.MonthSelect.Resize(fyne.NewSize(monthWidth, size.Height))
+	r.dp.DaySelect.Resize(fyne.NewSize(dayWidth, size.Height))
+
+	r.dp.YearSelect.Move(fyne.NewPos(0, 0))
+	r.dp.MonthSelect.Move(fyne.NewPos(yearWidth, 0))
+	r.dp.DaySelect.Move(fyne.NewPos(yearWidth+monthWidth, 0))
+}
+
+// MinSize implements fyne.WidgetRenderer.
+func (r *datePickerRenderer) MinSize() fyne.Size {
+	// Calculate the minimum size required for the DatePicker
+	yearMin := r.dp.YearSelect.MinSize()
+	monthMin := r.dp.MonthSelect.MinSize()
+	dayMin := r.dp.DaySelect.MinSize()
+
+	totalWidth := yearMin.Width + monthMin.Width + dayMin.Width
+	maxHeight := fyne.Max(yearMin.Height, fyne.Max(monthMin.Height, dayMin.Height))
+
+	return fyne.NewSize(totalWidth, maxHeight)
+}
+
+// Refresh implements fyne.WidgetRenderer.
+func (r *datePickerRenderer) Refresh() {
+	// Refresh the child widgets
+	r.dp.YearSelect.Refresh()
+	r.dp.MonthSelect.Refresh()
+	r.dp.DaySelect.Refresh()
+}
+
+// Objects implements fyne.WidgetRenderer.
+func (r *datePickerRenderer) Objects() []fyne.CanvasObject {
+	return []fyne.CanvasObject{
+		r.dp.YearSelect,
+		r.dp.MonthSelect,
+		r.dp.DaySelect,
+	}
+}
+
+// Destroy implements fyne.WidgetRenderer.
+func (r *datePickerRenderer) Destroy() {
+}
+
+// GetDate returns the selected date as a formatted string (YYYY-MM-DD).
+func (dp *DatePicker) GetDate() (string, error) {
+	selectedYear := dp.YearSelect.Selected
+	selectedMonth := dp.MonthSelect.Selected
+	selectedDay := dp.DaySelect.Selected
+
+	if selectedYear == "" || selectedMonth == "" || selectedDay == "" {
+		return "", fmt.Errorf("no date selected")
+	}
+
+	year := 0
+	month := 0
+	day := 0
+	fmt.Sscanf(selectedYear, "%d", &year)
+	fmt.Sscanf(selectedMonth, "%d", &month)
+	fmt.Sscanf(selectedDay, "%d", &day)
+
+	date := time.Date(year, time.Month(month), day, 0, 0, 0, 0, time.Local)
+	return date.Format("2006-01-02"), nil
+}
+
+// Helper functions
+func generateYears() []string {
+	var years []string
+	currentYear := time.Now().Year()
+	for year := currentYear; year >= 1960; year-- {
+		years = append(years, fmt.Sprintf("%d", year))
+	}
+	return years
+}
+
+func generateMonths() []string {
+	var months []string
+	for month := 1; month <= 12; month++ {
+		months = append(months, fmt.Sprintf("%02d", month)) // Format as two digits
+	}
+	return months
+}
+
+func generateDays(month int, year int) []string {
+	var days []string
+	daysInMonth := time.Date(year, time.Month(month+1), 0, 0, 0, 0, 0, time.Local).Day()
+	for day := 1; day <= daysInMonth; day++ {
+		days = append(days, fmt.Sprintf("%02d", day)) // Format as two digits
+	}
+	return days
+}

widget/datepicker_test.go

@@ -0,0 +1,32 @@
+package widget_test
+
+import (
+	"testing"
+	"time"
+
+	"fyne.io/fyne/v2/widget"
+	"github.com/stretchr/testify/assert"
+)
+
+func TestDatePicker(t *testing.T) {
+
+	dp := widget.NewDatePicker()
+
+	// Simulate selecting a date
+	dp.YearSelect.SetSelected("2025")
+	dp.MonthSelect.SetSelected("02")
+	dp.DaySelect.SetSelected("14")
+
+	// Get the formatted date string
+	dateStr, err := dp.GetDate()
+	assert.NoError(t, err)
+
+	// Parse the formatted string back into a time.Time object
+	date, err := time.Parse("2006-01-02", dateStr)
+	assert.NoError(t, err)
+
+	// Validate the parsed date
+	assert.Equal(t, 2025, date.Year())
+	assert.Equal(t, time.February, date.Month())
+	assert.Equal(t, 14, date.Day())
+}