feat(ui): allow temporarily revealing the UI with the alt button if hidden

app.go

@@ -70,6 +70,7 @@ type State struct {
 	RecentManager                 *gtk.RecentManager
 	BackgroundColorCssProvider    *gtk.CssProvider
 	PageCacheTrimTimeoutHandle    *glib.SourceHandle
+	UITemporarilyRevealed         bool
 }
 
 //go:embed about.jpg
@@ -236,6 +237,11 @@ func (app *App) handleKeyPress(key uint, shift bool, ctrl bool) {
 		} else {
 			app.W.MenuItemNextPage.Activate()
 		}
+	case gdk.KEY_Alt_L:
+		if app.Config.HideUI {
+			app.S.UITemporarilyRevealed = !app.S.UITemporarilyRevealed
+			app.toggleHideUI(!app.S.UITemporarilyRevealed)
+		}
 	}
 }
 

config.go

@@ -202,6 +202,7 @@ func (app *App) setHideUI(hideUI bool) {
 	app.Config.HideUI = hideUI
 	app.toggleHideUI(hideUI)
 	app.W.MenuItemHideUI.SetActive(hideUI)
+	app.S.UITemporarilyRevealed = false
 }
 
 func (app *App) setShrink(shrink bool) {

image_area.go

@@ -35,6 +35,12 @@ func (app *App) imageAreaInit() {
 	})
 
 	app.W.ScrolledWindow.Connect("button-press-event", func(self *gtk.ScrolledWindow, event *gdk.Event) bool {
+		if app.S.UITemporarilyRevealed {
+			app.S.UITemporarilyRevealed = false
+			app.toggleHideUI(true)
+			return true
+		}
+
 		be := &gdk.EventButton{Event: event}
 		switch be.Button() {
 		case 1: