golang fyne example

main.go

package main

import (
	"fmt"
	"time"

	"fyne.io/fyne/v2"
	"fyne.io/fyne/v2/app"
	"fyne.io/fyne/v2/container"
	"fyne.io/fyne/v2/data/binding"
	"fyne.io/fyne/v2/driver/desktop"
	"fyne.io/fyne/v2/widget"
)

var (
	altQ     = &desktop.CustomShortcut{KeyName: fyne.KeyQ, Modifier: fyne.KeyModifierAlt}
	altH     = &desktop.CustomShortcut{KeyName: fyne.KeyH, Modifier: fyne.KeyModifierAlt}
	altLeft  = &desktop.CustomShortcut{KeyName: fyne.KeyLeft, Modifier: fyne.KeyModifierAlt}
	altRight = &desktop.CustomShortcut{KeyName: fyne.KeyRight, Modifier: fyne.KeyModifierAlt}
)

func main() {
	myApp := app.New().NewWindow("Hello")
	quitItem := fyne.NewMenuItem("Quit", myApp.Close)
	quitItem.IsQuit = true
	quitItem.Shortcut = altQ
	fileMenu := fyne.NewMenu("File", quitItem)
	mainMenu := fyne.NewMainMenu(fileMenu)
	myApp.SetMainMenu(mainMenu)

	stringBind := binding.NewString()
	myEntryLeft := newMyEntryWithData(stringBind)
	updateEntryLeft := widget.NewButton("Update Left", myEntryLeft.updateFromBind)
	myEntryRight := newMyEntryWithData(stringBind)
	updateEntryRight := widget.NewButton("Update Right", myEntryRight.updateFromBind)

	sayHiButton := widget.NewButton(
		"Hi!",
		func() {
			if err := stringBind.Set("Welcome :)"); err != nil {
				fmt.Printf("Error %s\n", err)
			}
		},
	)
	clickQuitItem := func(shortcut fyne.Shortcut) {
		quitItem.Action()
	}
	clickUpdateEntryLeft := func(shortcut fyne.Shortcut) {
		updateEntryLeft.Tapped(nil)
	}
	clickUpdateEntryRight := func(shortcut fyne.Shortcut) {
		updateEntryRight.Tapped(nil)
	}
	clickHiButton := func(shortcut fyne.Shortcut) {
		sayHiButton.Tapped(nil)
	}

	setupShortcuts(myApp, clickHiButton, clickQuitItem, clickUpdateEntryLeft, clickUpdateEntryRight, myEntryLeft, myEntryRight)

	floatBind := binding.NewFloat()
	progressBar1 := widget.NewProgressBarWithData(floatBind)
	progressBar2 := widget.NewProgressBarWithData(floatBind)
	periodicallyIncrease(floatBind)

	myApp.SetContent(
		container.NewVBox(
			container.NewStack(
				container.NewGridWithColumns(
					2,
					container.NewVBox(
						container.NewStack(myEntryLeft),
						updateEntryLeft,
					),
					container.NewVBox(
						container.NewStack(myEntryRight),
						updateEntryRight,
					),
				),
			),
			sayHiButton,
			container.NewGridWithColumns(
				2,
				progressBar1,
				progressBar2,
			),
		),
	)

	myApp.ShowAndRun()
}

func setupShortcuts(myApp fyne.Window, sayHiKeyAction func(shortcut fyne.Shortcut), closeAppKeyAction func(shortcut fyne.Shortcut), updateLeftKeyAction func(shortcut fyne.Shortcut), updateRightKeyAction func(shortcut fyne.Shortcut), myEntryLeft *myEntry, myEntryRight *myEntry) {
	myApp.Canvas().AddShortcut(altH, sayHiKeyAction)
	myApp.Canvas().AddShortcut(altQ, closeAppKeyAction)
	myApp.Canvas().AddShortcut(altLeft, updateLeftKeyAction)
	myApp.Canvas().AddShortcut(altRight, updateRightKeyAction)

	myEntryLeft.AddShortcut(altH, sayHiKeyAction)
	myEntryLeft.AddShortcut(altQ, closeAppKeyAction)
	myEntryLeft.AddShortcut(altLeft, updateLeftKeyAction)
	myEntryLeft.AddShortcut(altRight, updateRightKeyAction)

	myEntryRight.AddShortcut(altH, sayHiKeyAction)
	myEntryRight.AddShortcut(altQ, closeAppKeyAction)
	myEntryRight.AddShortcut(altLeft, updateLeftKeyAction)
	myEntryRight.AddShortcut(altRight, updateRightKeyAction)
}

func periodicallyIncrease(floatBind binding.Float) {
	go func() {
		for {
			if value, err := floatBind.Get(); err != nil {
				fmt.Printf("Error: %s\n", err)
			} else {
				time.Sleep(50 * time.Millisecond)
				if value > 1 {
					value = 0
				}
				if err := floatBind.Set(value + 0.01); err != nil {
					fmt.Printf("Error: %s\n", err)
				}
			}
		}
	}()
}

type myEntry struct {
	widget.Entry
	stringBind binding.String
	shortcuts  map[string]func(fyne.Shortcut)
}

func newMyEntryWithData(data binding.String) *myEntry {
	myEntry := &myEntry{widget.Entry{Wrapping: fyne.TextWrapWord, MultiLine: true}, data, nil}
	myEntry.ExtendBaseWidget(myEntry)
	myEntry.shortcuts = make(map[string]func(fyne.Shortcut))
	myEntry.Bind(data)
	myEntry.Validator = nil
	return myEntry
}

func (m *myEntry) updateFromBind() {
	if text, err := m.stringBind.Get(); err == nil {
		m.Entry.SetText(text)
		m.Refresh()
	} else {
		fmt.Printf("Error: %s", err)
	}
}

func (m *myEntry) TypedShortcut(s fyne.Shortcut) {
	if _, ok := s.(*desktop.CustomShortcut); !ok {
		m.Entry.TypedShortcut(s)
	}
	if function := m.shortcuts[s.ShortcutName()]; function != nil {
		function(s)
	}
}

func (m *myEntry) AddShortcut(shortcut fyne.Shortcut, action func(fyne.Shortcut)) {
	m.shortcuts[shortcut.ShortcutName()] = action
}