A handle to the new window indicates success. NULL indicates failure. To get extended error information, call GetLastError.

Here, failure to create a window initiates DEBUGMSG:

    g_hwndMain =  CreateWindow  (
        TEXT ("AnxJTest Class"),
        lpstrWndTitle,
        WS_VISIBLE,
        0, 0, SCREEN_WIDTH, SCREEN_HEIGHT,
        NULL, NULL, g_hInstance, NULL);
    if (!g_hwndMain) {
        DEBUGMSG(ZONE_VERBOSE | ZONE_ERROR, 
(TEXT ("Could not create main window.")));
        return FALSE;
}

The CreateWindow function does not support the WM_PARENTNOTIFY message.

CreateWindow is implemented as a macro. It is defined as CreateWindowEx, but with the dwExStyle parameter set to 0L.

Menu bars are not supported. The hMenu parameter must be NULL, unless it is used as a child-window identifier.

The MDICLIENT window class is not supported.

The dwStyle parameter can be a combination of the window styles and control styles documented in Window and Message Box Styles and Control Styles.

The following dwStyle flags are not supported for Windows Embedded CE:

The following dwStyle flags are not supported for controls and dialog boxes:

You can use the BS_OWNERDRAW style as a substitute for the BS_USERBUTTON style.

Combine the BS_MULTILINE style with the BS_PUSHBUTTON style to wrap text on a button.

You can use the SS_LEFT or SS_LEFTNOWORDWRAP style instead of the SS_SIMPLE style for static controls.

All windows implicitly have the WS_CLIPSIBLINGS and WS_CLIPCHILDREN styles.

Windows CE 1.0 does not support owned windows, except for dialog boxes. If the hwndParent parameter is not NULL, the window is implicitly given the WS_CHILD style.

Windows CE 1.0 does not support menu bars.

For Windows CE 2.10 and later, if nWidth and nHeight are set to CW_USEDEFAULT, the child window has dimensions of 0 x 0.

Before returning, CreateWindow sends a WM_CREATE message to the window procedure. For overlapped, pop-up, and child windows, CreateWindow sends WM_CREATE messages to the window. The lParam parameter of the WM_CREATE message contains a pointer to a CREATESTRUCT structure. If the WS_VISIBLE style is specified, CreateWindow sends the window all the messages required to activate and show the window.

The following predefined control classes can be specified in the lpClassName parameter. Note the corresponding control styles you can use in the dwStyle parameter.

BUTTON

Designates a small rectangular child window that represents a button the user can click to turn it on or off. Button controls can be used alone or in groups, and they can either be labeled or appear without text. Button controls typically change appearance when the user clicks them. For more information about buttons and the styles you can specify in the dwStyle parameter, see Control Styles.

COMBOBOX

Designates a control consisting of a list box and a selection field similar to an edit control. When using this style, an application should either display the list box at all times or enable a drop-down list box. If the list box is visible, typing characters into the selection field highlights the first list box entry that matches the characters typed. Conversely, selecting an item in the list box displays the selected text in the selection field. For more information, see Combo Boxes. For a table of the combo box styles you can specify in the dwStyle parameter, see Combo Box Styles.

EDIT

Designates a rectangular child window into which the user can type text from the keyboard. The user selects the control and gives it the keyboard focus by clicking it or moving to it by pressing the TAB key. The user can type text when the edit control displays a flashing caret; use the mouse to move the cursor, select characters to be replaced, or position the cursor for inserting characters; or use the BACKSPACE key to delete characters. For more information about edit controls and the styles you can specify in the dwStyle parameter, see Control Styles.

LISTBOX

Designates a list of character strings. Specify this control whenever an application must present a list of names, such as filenames, from which the user can choose. The user can select a string by clicking it. A selected string is highlighted, and a notification message is passed to the parent window. For more information about list boxes and the styles you can specify in the dwStyle parameter, see Control Styles.

MDICLIENT

Designates an MDI client window. This window receives messages that control the MDI application's child windows. The recommended style bits are WS_CLIPCHILDREN and WS_CHILD. Specify the WS_HSCROLL and WS_VSCROLL styles to create an MDI client window that allows the user to scroll MDI child windows into view.

RICHEDIT

Designates a Rich Edit 1.0 control. This window lets the user view and edit text with character and paragraph formatting, and can include embedded COM objects.

RICHEDIT_CLASS

Designates a Rich Edit 2.0 control. This control lets the user view and edit text with character and paragraph formatting, and can include embedded COM objects. Windows Mobile 6 Professional and Windows Mobile 6 Classic do not support this control class.

SCROLLBAR

Designates a rectangle that contains a scroll box and has direction arrows at both ends. The scroll bar sends a notification message to its parent window whenever the user clicks the control. The parent window is responsible for updating the position of the scroll box, if necessary. For more information about scroll bars and the styles you can specify in the dwStyle parameter, see Control Styles.

STATIC

Designates a simple text field, box, or rectangle used to label, box, or separate other controls. Static controls take no input and provide no output. For more information about static controls and the styles you can specify in the dwStyle parameter, see Control Styles.

Note:
If you specify Windows 4.x when linking your application, its windows cannot have caption buttons unless they also have window menus. This is not a requirement if you specify Windows 3.x when linking your application.

Reference