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CreateDialogIndirectParam info  Overview  Group

The CreateDialogIndirectParam function 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.

HWND CreateDialogIndirectParam(

    HINSTANCE hInstance,

// handle to application instance

    LPCDLGTEMPLATE lpTemplate,

// pointer to dialog box template

    HWND hWndParent,

// handle to owner window

    DLGPROC lpDialogFunc,

// pointer to dialog box procedure

    LPARAM lParamInit 

// initialization value

   );

Parameters

hInstance
Identifies the instance of the module that will create the dialog box.
lpTemplate
Pointer to a global memory object containing a template that 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.

hWndParent
Identifies the window that owns the dialog box.
lpDialogFunc
Points to the dialog box procedure. For more information about the dialog box procedure, see DialogProc.
lParamInit
Specifies the value to pass to the dialog box in the lParam parameter of the WM_INITDIALOG message.

Return Values

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 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.

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 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. To create code that works on both Windows NT and Windows 95, use the MultiByteToWideChar function to generate these Unicode strings.

Windows 95: The system can support a maximum of 16,364 window handles.

See Also

CreateDialog, CreateDialogIndirect, CreateDialogParam, CreateWindowEx, DestroyWindow, DialogProc, DLGITEMTEMPLATE, DLGITEMTEMPLATEEX, DLGTEMPLATE, DLGTEMPLATEEX, MultiByteToWideChar, ShowWindow, WM_INITDIALOG, WM_SETFONT