Refactor application structure and initialize core components

I decided to rewrite the program taking into account the experience gained.

internal/gui/view/convertor.go

@@ -0,0 +1,33 @@
+package view
+
+import (
+	"fyne.io/fyne/v2"
+	"fyne.io/fyne/v2/container"
+	"fyne.io/fyne/v2/lang"
+	"fyne.io/fyne/v2/widget"
+)
+
+func Convertor() fyne.CanvasObject {
+	form := newFormConvertor()
+
+	converterVideoFilesTitle := lang.L("converterVideoFilesTitle")
+	return widget.NewCard(converterVideoFilesTitle, "", container.NewVScroll(form.getForm()))
+}
+
+type formConvertor struct {
+	form  *widget.Form
+	items []*widget.FormItem
+}
+
+func newFormConvertor() *formConvertor {
+	f := widget.NewForm()
+	f.SubmitText = lang.L("converterVideoFilesSubmitTitle")
+
+	return &formConvertor{
+		form: f,
+	}
+}
+
+func (f *formConvertor) getForm() *widget.Form {
+	return f.form
+}

internal/gui/view/error.go

@@ -0,0 +1,39 @@
+package view
+
+import (
+	"fyne.io/fyne/v2"
+	"fyne.io/fyne/v2/container"
+	"fyne.io/fyne/v2/lang"
+	"fyne.io/fyne/v2/widget"
+	"git.kor-elf.net/kor-elf/gui-for-ffmpeg/internal/application/setting"
+)
+
+func StartWithError(err error, languages []setting.Lang, funcSelected func(lang setting.Lang)) fyne.CanvasObject {
+	messageHead := lang.L("error")
+
+	listView := widget.NewList(
+		func() int {
+			return len(languages)
+		},
+		func() fyne.CanvasObject {
+			return widget.NewLabel("template")
+		},
+		func(i widget.ListItemID, o fyne.CanvasObject) {
+			block := o.(*widget.Label)
+			block.SetText(languages[i].Title)
+		})
+	listView.OnSelected = func(id widget.ListItemID) {
+		funcSelected(languages[id])
+	}
+
+	return container.NewBorder(
+		container.NewVBox(
+			widget.NewLabel(messageHead),
+			widget.NewLabel(err.Error()),
+		),
+		nil,
+		nil,
+		nil,
+		listView,
+	)
+}

internal/gui/view/start_without_support_lang.go

@@ -0,0 +1,28 @@
+package view
+
+import (
+	"fyne.io/fyne/v2"
+	"fyne.io/fyne/v2/lang"
+	"fyne.io/fyne/v2/widget"
+	"git.kor-elf.net/kor-elf/gui-for-ffmpeg/internal/application/setting"
+)
+
+func StartWithoutSupportLang(languages []setting.Lang, funcSelected func(lang setting.Lang)) fyne.CanvasObject {
+	listView := widget.NewList(
+		func() int {
+			return len(languages)
+		},
+		func() fyne.CanvasObject {
+			return widget.NewLabel("template")
+		},
+		func(i widget.ListItemID, o fyne.CanvasObject) {
+			block := o.(*widget.Label)
+			block.SetText(languages[i].Title)
+		})
+	listView.OnSelected = func(id widget.ListItemID) {
+		funcSelected(languages[id])
+	}
+
+	messageHead := lang.L("languageSelectionHead")
+	return widget.NewCard(messageHead, "", listView)
+}