DialogBoxIndirectParam function (Windows)

Applies to: desktop apps only

Creates a modal dialog box from a dialog box template in memory. Before displaying the dialog box, the function passes an application-defined value to the dialog box procedure as the lParam parameter of the WM_INITDIALOG message. An application can use this value to initialize dialog box controls.

Syntax

INT_PTR WINAPI DialogBoxIndirectParam(
  __in_opt  HINSTANCE hInstance,
  __in      LPCDLGTEMPLATE hDialogTemplate,
  __in_opt  HWND hWndParent,
  __in_opt  DLGPROC lpDialogFunc,
  __in      LPARAM dwInitParam
);

Parameters

hInstance [in, optional]

Type: HINSTANCE

A handle to the module that creates the dialog box.

hDialogTemplate [in]

Type: LPCDLGTEMPLATE

The template that DialogBoxIndirectParam uses to create the dialog box. A dialog box template consists of a header that describes the dialog box, followed by one or more additional blocks of data that describe each of the controls in the dialog box. The template can use either the standard format or the extended format.

In a standard template for a dialog box, the header is a DLGTEMPLATE structure followed by additional variable-length arrays. The data for each control consists of a DLGITEMTEMPLATE structure followed by additional variable-length arrays.

In an extended template for a dialog box, the header uses the DLGTEMPLATEEX format and the control definitions use the DLGITEMTEMPLATEEX format.

hWndParent [in, optional]

Type: HWND

A handle to the window that owns the dialog box.

lpDialogFunc [in, optional]

Type: DLGPROC

A pointer to the dialog box procedure. For more information about the dialog box procedure, see DialogProc.

dwInitParam [in]

Type: LPARAM

The value to pass to the dialog box in the lParam parameter of the WM_INITDIALOG message.

Return value

Type: INT_PTR

If the function succeeds, the return value is the nResult parameter specified in the call to the EndDialog function that was used to terminate the dialog box.

If the function fails because the hWndParent parameter is invalid, the return value is zero. The function returns zero in this case for compatibility with previous versions of Windows. If the function fails for any other reason, the return value is –1. To get extended error information, call GetLastError.

Remarks

The DialogBoxIndirectParam function uses the CreateWindowEx function to create the dialog box. DialogBoxIndirectParam then sends a WM_INITDIALOG message to the dialog box procedure. If the template specifies the DS_SETFONT or DS_SHELLFONT style, the function also sends a WM_SETFONT message to the dialog box procedure. The function displays the dialog box (regardless of whether the template specifies the WS_VISIBLE style), disables the owner window, and starts its own message loop to retrieve and dispatch messages for the dialog box.

When the dialog box procedure calls the EndDialog function, DialogBoxIndirectParam destroys the dialog box, ends the message loop, enables the owner window (if previously enabled), and returns the nResult parameter specified by the dialog box procedure when it called EndDialog.

In a standard dialog box template, the DLGTEMPLATE structure and each of the DLGITEMTEMPLATE structures must be aligned on DWORD boundaries. The creation data array that follows a DLGITEMTEMPLATE structure must also be aligned on a DWORD boundary. All of the other variable-length arrays in the template must be aligned on WORD boundaries.

In an extended dialog box template, the DLGTEMPLATEEX header and each of the DLGITEMTEMPLATEEX control definitions must be aligned on DWORD boundaries. The creation data array, if any, that follows a DLGITEMTEMPLATEEX structure must also be aligned on a DWORD boundary. All of the other variable-length arrays in the template must be aligned on WORD boundaries.

All character strings in the dialog box template, such as titles for the dialog box and buttons, must be Unicode strings.

Requirements

See also

Reference

CreateWindowEx

DialogBox

DialogBoxIndirect

DialogBoxParam

DialogProc

DLGITEMTEMPLATE

DLGITEMTEMPLATEEX

DLGTEMPLATE

DLGTEMPLATEEX

EndDialog

WM_INITDIALOG

WM_SETFONT

Conceptual

Dialog Boxes

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Build date: 2/10/2012