INSTALLUI_HANDLERA callback function (msi.h)

The INSTALLUI_HANDLER function prototype defines a callback function that the installer calls for progress notification and error messages. For more information on the usage of this function prototype, a sample code snippet is available in Handling Progress Messages Using MsiSetExternalUI.

Syntax

INSTALLUI_HANDLERA InstalluiHandlera;

int InstalluiHandlera(
  LPVOID pvContext,
  UINT iMessageType,
  LPCSTR szMessage
)
{...}

Parameters

pvContext

Pointer to an application context passed to the MsiSetExternalUI function. This parameter can be used for error checking.

iMessageType

Specifies a combination of one message box style, one message box icon type, one default button, and one installation message type. This parameter must be one of the following.

Message box StylesFlag Meaning
MB_ABORTRETRYIGNORE
The message box contains the Abort, Retry, and Ignore buttons.
MB_OK
The message box contains the OK button. This is the default.
MB_OKCANCEL
The message box contains the OK and Cancel buttons.
MB_RETRYCANCEL
The message box contains the Retry and Cancel buttons.
MB_YESNO
The message box contains the Yes and No buttons.
MB_YESNOCANCEL
The message box contains the Yes, No, and Cancel buttons.
 
Message box IconTypesFlag Meaning
MB_ICONEXCLAMATION, MB_ICONWARNING
An exclamation point appears in the message box.
MB_ICONINFORMATION, MB_ICONASTERISK
The information sign appears in the message box.
MB_ICONQUESTION
A question mark appears in the message box.
MB_ICONSTOP, MB_ICONERROR, MB_ICONHAND
A stop sign appears in the message box.
 
Default ButtonsFlag Meaning
MB_DEFBUTTON1
The first button is the default button.
MB_DEFBUTTON2
The second button is the default button.
MB_DEFBUTTON3
The third button is the default button.
 
Install message TypesFlag Meaning
INSTALLMESSAGE_FATALEXIT
Premature termination
INSTALLMESSAGE_ERROR
Formatted error message
INSTALLMESSAGE_WARNING
Formatted warning message
INSTALLMESSAGE_USER
User request message.
INSTALLMESSAGE_INFO
Informative message for log
INSTALLMESSAGE_FILESINUSE
List of files currently in use that must be closed before being replaced.
INSTALLMESSAGE_RESOLVESOURCE
Request to determine a valid source location
INSTALLMESSAGE_RMFILESINUSE
List of files currently in use that must be closed before being replaced. Available beginning with Windows Installer 4.0. For more information about this message see Using Restart Manager with an External UI.
INSTALLMESSAGE_OUTOFDISKSPACE
Insufficient disk space message
INSTALLMESSAGE_ACTIONSTART
Start of action message. This message includes the action name and description.
INSTALLMESSAGE_ACTIONDATA
Formatted data associated with the individual action item.
INSTALLMESSAGE_PROGRESS
Progress gauge information. This message includes information on units so far and total number of units.
INSTALLMESSAGE_COMMONDATA
Formatted dialog information for user interface.
INSTALLMESSAGE_INITIALIZE
Sent prior to UI initialization, no string data
INSTALLMESSAGE_TERMINATE
Sent after UI termination, no string data
INSTALLMESSAGE_SHOWDIALOG
Sent prior to display of authored dialog or wizard
INSTALLMESSAGE_INSTALLSTART
Sent prior to installation of product.
INSTALLMESSAGE_INSTALLEND
Sent after installation of product.
 
 

The following defaults should be used if any of the preceding messages are missing: MB_OK, no icon, and MB_DEFBUTTON1. There is no default installation message type; a message type is always specified.

szMessage

Specifies the message text.

Return value

The following return values map to the buttons specified by the message box style:

IDOK

 
IDCANCEL
 
IDABORT
 
IDRETRY
 
IDIGNORE
 
IDYES
 
IDNO

Remarks

For more information on returning values from an external user interface handler, see the Returning Values from an External User Interface Handler topic.

Note

The msi.h header defines INSTALLUI_HANDLER as an alias which automatically selects the ANSI or Unicode version of this function based on the definition of the UNICODE preprocessor constant. Mixing usage of the encoding-neutral alias with code that not encoding-neutral can lead to mismatches that result in compilation or runtime errors. For more information, see Conventions for Function Prototypes.

Requirements

Requirement Value
Minimum supported client Windows Installer 5.0 on Windows Server 2012, Windows 8, Windows Server 2008 R2 or Windows 7. Windows Installer 4.0 or Windows Installer 4.5 on Windows Server 2008 or Windows Vista. Windows Installer on Windows Server 2003 or Windows XP
Target Platform Windows
Header msi.h

See also

MsiSetExternalUI