CreateDialogIndirectParamA function (winuser.h)

Creates a modeless 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

HWND CreateDialogIndirectParamA(
  [in, optional] HINSTANCE       hInstance,
  [in]           LPCDLGTEMPLATEA lpTemplate,
  [in, optional] HWND            hWndParent,
  [in, optional] DLGPROC         lpDialogFunc,
  [in]           LPARAM          dwInitParam
);

Parameters

[in, optional] hInstance

Type: HINSTANCE

A handle to the module which contains the dialog box template. If this parameter is NULL, then the current executable is used.

[in] lpTemplate

Type: LPCDLGTEMPLATE

The template CreateDialogIndirectParam 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, 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 dialog box template, the header uses the DLGTEMPLATEEX format and the control definitions use the DLGITEMTEMPLATEEX format.

After CreateDialogIndirectParam returns, you can free the template, which is only used to get the dialog box started.

[in, optional] hWndParent

Type: HWND

A handle to the window that owns the dialog box.

[in, optional] lpDialogFunc

Type: DLGPROC

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

[in] dwInitParam

Type: LPARAM

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

Return value

Type: HWND

If the function succeeds, the return value is the window handle to the dialog box.

If the function fails, the return value is NULL. To get extended error information, call GetLastError.

Remarks

The CreateDialogIndirectParam function uses the CreateWindowEx function to create the dialog box. CreateDialogIndirectParam 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 if the template specifies the WS_VISIBLE style. Finally, CreateDialogIndirectParam returns the window handle to the dialog box.

After CreateDialogIndirectParam returns, you can use the ShowWindow function to display the dialog box (if it is not already visible). To destroy the dialog box, use the DestroyWindow function. To support keyboard navigation and other dialog box functionality, the message loop for the dialog box must call the IsDialogMessage function.

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.

Note

The winuser.h header defines CreateDialogIndirectParam 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 2000 Professional [desktop apps only]
Minimum supported server Windows 2000 Server [desktop apps only]
Target Platform Windows
Header winuser.h (include Windows.h)
Library User32.lib
DLL User32.dll
API set ext-ms-win-ntuser-dialogbox-l1-1-0 (introduced in Windows 8)

See also

Conceptual

CreateDialog

CreateDialogIndirect

CreateDialogParam

CreateWindowEx

DLGITEMTEMPLATE

DLGITEMTEMPLATEEX

DLGTEMPLATE

DLGTEMPLATEEX

DestroyWindow

Dialog Boxes

DialogProc

MultiByteToWideChar

Other Resources

Reference

ShowWindow

WM_INITDIALOG

WM_SETFONT