Add FFplay help feature and keyboard shortcut guide

Introduced a new "Help FFplay" section in the help menu to provide information about FFplay player keyboard shortcuts and actions.

menu/view.go

@@ -4,6 +4,7 @@ import (
 	"fyne.io/fyne/v2"
 	"fyne.io/fyne/v2/canvas"
 	"fyne.io/fyne/v2/container"
+	"fyne.io/fyne/v2/theme"
 	"fyne.io/fyne/v2/widget"
 	"git.kor-elf.net/kor-elf/gui-for-ffmpeg/kernel"
 	"github.com/nicksnyder/go-i18n/v2/i18n"
@@ -14,6 +15,7 @@ import (
 type ViewContract interface {
 	About(ffmpegVersion string, ffprobeVersion string, ffplayVersion string)
 	Gratitude()
+	HelpFFplay()
 }
 
 type View struct {
@@ -144,6 +146,151 @@ func (v View) About(ffmpegVersion string, ffprobeVersion string, ffplayVersion s
 	view.Show()
 }
 
+func (v View) HelpFFplay() {
+	view := v.app.GetAppFyne().NewWindow(v.app.GetLocalizerService().GetMessage(&i18n.LocalizeConfig{
+		MessageID: "helpFFplay",
+	}))
+	view.Resize(fyne.Size{Width: 800, Height: 550})
+	view.SetFixedSize(true)
+
+	data := [][]string{
+		[]string{
+			v.app.GetLocalizerService().GetMessage(&i18n.LocalizeConfig{
+				MessageID: "helpFFplayKeys",
+			}),
+			v.app.GetLocalizerService().GetMessage(&i18n.LocalizeConfig{
+				MessageID: "helpFFplayDescription",
+			}),
+		},
+		[]string{
+			"Q, ESC",
+			v.app.GetLocalizerService().GetMessage(&i18n.LocalizeConfig{
+				MessageID: "helpFFplayQuit",
+			}),
+		},
+		[]string{
+			"F, " + v.app.GetLocalizerService().GetMessage(&i18n.LocalizeConfig{
+				MessageID: "helpFFplayDoubleClickLeftMouseButton",
+			}),
+			v.app.GetLocalizerService().GetMessage(&i18n.LocalizeConfig{
+				MessageID: "helpFFplayToggleFullScreen",
+			}),
+		},
+		[]string{
+			"P, " +
+				v.app.GetLocalizerService().GetMessage(&i18n.LocalizeConfig{
+					MessageID: "helpFFplayKeySpace",
+				}),
+			v.app.GetLocalizerService().GetMessage(&i18n.LocalizeConfig{
+				MessageID: "helpFFplayPause",
+			}),
+		},
+		[]string{
+			"M",
+			v.app.GetLocalizerService().GetMessage(&i18n.LocalizeConfig{
+				MessageID: "helpFFplayToggleMute",
+			}),
+		},
+		[]string{
+			"9, /",
+			v.app.GetLocalizerService().GetMessage(&i18n.LocalizeConfig{
+				MessageID: "helpFFplayDecreaseVolume",
+			}),
+		},
+		[]string{
+			"0, *",
+			v.app.GetLocalizerService().GetMessage(&i18n.LocalizeConfig{
+				MessageID: "helpFFplayIncreaseVolume",
+			}),
+		},
+		[]string{
+			v.app.GetLocalizerService().GetMessage(&i18n.LocalizeConfig{
+				MessageID: "helpFFplayKeyLeft",
+			}),
+			v.app.GetLocalizerService().GetMessage(&i18n.LocalizeConfig{
+				MessageID: "helpFFplaySeekBackward10Seconds",
+			}),
+		},
+		[]string{
+			v.app.GetLocalizerService().GetMessage(&i18n.LocalizeConfig{
+				MessageID: "helpFFplayKeyRight",
+			}),
+			v.app.GetLocalizerService().GetMessage(&i18n.LocalizeConfig{
+				MessageID: "helpFFplaySeekForward10Seconds",
+			}),
+		},
+		[]string{
+			v.app.GetLocalizerService().GetMessage(&i18n.LocalizeConfig{
+				MessageID: "helpFFplayKeyDown",
+			}),
+			v.app.GetLocalizerService().GetMessage(&i18n.LocalizeConfig{
+				MessageID: "helpFFplaySeekBackward1Minute",
+			}),
+		},
+		[]string{
+			v.app.GetLocalizerService().GetMessage(&i18n.LocalizeConfig{
+				MessageID: "helpFFplayKeyUp",
+			}),
+			v.app.GetLocalizerService().GetMessage(&i18n.LocalizeConfig{
+				MessageID: "helpFFplaySeekBForward1Minute",
+			}),
+		},
+		[]string{
+			"Page Down",
+			v.app.GetLocalizerService().GetMessage(&i18n.LocalizeConfig{
+				MessageID: "helpFFplaySeekBackward10Minutes",
+			}),
+		},
+		[]string{
+			"Page Up",
+			v.app.GetLocalizerService().GetMessage(&i18n.LocalizeConfig{
+				MessageID: "helpFFplaySeekBForward10Minutes",
+			}),
+		},
+		[]string{
+			"S, " + v.app.GetLocalizerService().GetMessage(&i18n.LocalizeConfig{
+				MessageID: "helpFFplayKeyHoldS",
+			}),
+			v.app.GetLocalizerService().GetMessage(&i18n.LocalizeConfig{
+				MessageID: "helpFFplayActivateFrameStepMode",
+			}),
+		},
+		[]string{
+			"W",
+			v.app.GetLocalizerService().GetMessage(&i18n.LocalizeConfig{
+				MessageID: "helpFFplayCycleVideoFiltersOrShowModes",
+			}),
+		},
+	}
+
+	list := widget.NewTable(
+		func() (int, int) {
+			return len(data), len(data[0])
+		},
+		func() fyne.CanvasObject {
+			return widget.NewLabel("")
+		},
+		func(i widget.TableCellID, o fyne.CanvasObject) {
+			if i.Row == 0 {
+				o.(*widget.Label).TextStyle.Bold = true
+				o.(*widget.Label).SizeName = theme.SizeNameSubHeadingText
+			}
+			if i.Col == 0 {
+				o.(*widget.Label).TextStyle.Bold = true
+			}
+			o.(*widget.Label).SetText(data[i.Row][i.Col])
+		})
+	list.SetRowHeight(0, 40)
+	list.SetColumnWidth(0, 200)
+	list.SetColumnWidth(1, 585)
+	list.SetRowHeight(2, 55)
+	view.SetContent(
+		container.NewScroll(list),
+	)
+	view.CenterOnScreen()
+	view.Show()
+}
+
 func (v View) getCopyright() *widget.RichText {
 	return widget.NewRichTextFromMarkdown("Copyright (c) 2024 **[Leonid Nikitin (kor-elf)](https://git.kor-elf.net/kor-elf/)**.")
 }