showed an error message if the client cannot connect to a host (#910)

d2app/app.go

@@ -894,10 +894,10 @@ func (a *App) updateInitError(target d2interface.Surface) error {
 }
 
 // ToMainMenu forces the game to transition to the Main Menu
-func (a *App) ToMainMenu() {
+func (a *App) ToMainMenu(errorMessageOptional ...string) {
 	buildInfo := d2gamescreen.BuildInfo{Branch: a.gitBranch, Commit: a.gitCommit}
 
-	mainMenu, err := d2gamescreen.CreateMainMenu(a, a.asset, a.renderer, a.inputManager, a.audio, a.ui, buildInfo)
+	mainMenu, err := d2gamescreen.CreateMainMenu(a, a.asset, a.renderer, a.inputManager, a.audio, a.ui, buildInfo, errorMessageOptional...)
 	if err != nil {
 		log.Print(err)
 		return
@@ -925,12 +925,14 @@ func (a *App) ToCreateGame(filePath string, connType d2clientconnectiontype.Clie
 	}
 
 	if err = gameClient.Open(host, filePath); err != nil {
-		// https://github.com/OpenDiablo2/OpenDiablo2/issues/805
+		errorMessage := fmt.Sprintf("can not connect to the host: %s", host)
-		fmt.Printf("can not connect to the host: %s", host)
+		fmt.Println(errorMessage)
+		a.ToMainMenu(errorMessage)
+	} else {
+		a.screen.SetNextScreen(d2gamescreen.CreateGame(
+			a, a.asset, a.ui, a.renderer, a.inputManager, a.audio, gameClient, a.terminal, a.guiManager,
+		))
 	}
-
-	a.screen.SetNextScreen(d2gamescreen.CreateGame(a, a.asset, a.ui, a.renderer, a.inputManager,
-		a.audio, gameClient, a.terminal, a.guiManager))
 }
 
 // ToCharacterSelect forces the game to transition to the Character Select (load character) screen

d2common/d2interface/navigate.go

@@ -6,7 +6,7 @@ import (
 
 // Navigator is used for transitioning between game screens
 type Navigator interface {
-	ToMainMenu()
+	ToMainMenu(errorMessageOptional ...string)
 	ToSelectHero(connType d2clientconnectiontype.ClientConnectionType, connHost string)
 	ToCreateGame(filePath string, connType d2clientconnectiontype.ClientConnectionType, connHost string)
 	ToCharacterSelect(connType d2clientconnectiontype.ClientConnectionType, connHost string)

d2game/d2gamescreen/main_menu.go

@@ -59,12 +59,14 @@ const (
 	networkCancelBtnX, networkCancelBtnY     = 264, 540
 	tcpHostBtnX, tcpHostBtnY                 = 264, 280
 	tcpJoinBtnX, tcpJoinBtnY                 = 264, 320
+	errorLabelX, errorLabelY                 = 400, 250
 )
 
 const (
 	white       = 0xffffffff
 	lightYellow = 0xffff8cff
 	gold        = 0xd8c480ff
+	red         = 0xff0000ff
 )
 
 const (
@@ -107,6 +109,7 @@ type MainMenu struct {
 	commitLabel         *d2ui.Label
 	tcpIPOptionsLabel   *d2ui.Label
 	tcpJoinGameLabel    *d2ui.Label
+	errorLabel          *d2ui.Label
 	tcpJoinGameEntry    *d2ui.TextBox
 	screenMode          mainMenuScreenMode
 	leftButtonHeld      bool
@@ -132,6 +135,7 @@ func CreateMainMenu(
 	audioProvider d2interface.AudioProvider,
 	ui *d2ui.UIManager,
 	buildInfo BuildInfo,
+	errorMessageOptional ...string,
 ) (*MainMenu, error) {
 	heroStateFactory, err := d2hero.NewHeroStateFactory(asset)
 	if err != nil {
@@ -151,6 +155,11 @@ func CreateMainMenu(
 		heroState:      heroStateFactory,
 	}
 
+	if len(errorMessageOptional) != 0 {
+		mainMenu.errorLabel = ui.NewLabel(d2resource.FontFormal12, d2resource.PaletteUnits)
+		mainMenu.errorLabel.SetText(errorMessageOptional[0])
+	}
+
 	return mainMenu, nil
 }
 
@@ -258,6 +267,12 @@ func (v *MainMenu) createLabels(loading d2screen.LoadingState) {
 	v.tcpJoinGameLabel.Color[0] = rgbaColor(gold)
 
 	v.tcpJoinGameLabel.SetPosition(joinGameX, joinGameY)
+
+	if v.errorLabel != nil {
+		v.errorLabel.SetPosition(errorLabelX, errorLabelY)
+		v.errorLabel.Alignment = d2gui.HorizontalAlignCenter
+		v.errorLabel.Color[0] = rgbaColor(red)
+	}
 }
 
 func (v *MainMenu) createLogos(loading d2screen.LoadingState) {
@@ -454,6 +469,10 @@ func (v *MainMenu) renderLabels(screen d2interface.Surface) {
 	case ScreenModeTrademark:
 		v.copyrightLabel.Render(screen)
 		v.copyrightLabel2.Render(screen)
+
+		if v.errorLabel != nil {
+			v.errorLabel.Render(screen)
+		}
 	case ScreenModeMainMenu:
 		v.openDiabloLabel.Render(screen)
 		v.versionLabel.Render(screen)