Question

I try to get a localized message box in the .onInit method which fails with the following code:

!insertmacro MUI_LANGUAGE "English"
!insertmacro MUI_LANGUAGE "German"

LangString Message ${LANG_ENGLISH} "This is a message."
LangString Message ${LANG_GERMAN} "Dies ist eine Nachricht"

Function .onInit
  !insertmacro MUI_LANGDLL_DISPLAY
  MessageBox MB_OK "$(Message)"
FunctionEnd

The MessageBox always shows the same language string.

Answer 1

The Problem is, that the language is processed after the .onInit method.

A workaround for this could be to put the custom code from the .onInit method to the .onGUIInit method.

With MUI2 this is done as follows:

!define MUI_CUSTOMFUNCTION_GUIINIT myGuiInit

!include "MUI2.nsh"

!insertmacro MUI_LANGUAGE "English"
!insertmacro MUI_LANGUAGE "German"

LangString Message ${LANG_ENGLISH} "This is a message."
LangString Message ${LANG_GERMAN} "Dies ist eine Nachricht"

Function .onInit
  !insertmacro MUI_LANGDLL_DISPLAY
FunctionEnd

Function myGuiInit
  MessageBox MB_OK "$(Message)"
FunctionEnd

Now the MessageBox should show the correctly localized message.