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 DLGITEMTEMPLATE

The DLGITEMTEMPLATE structure defines the dimensions and style of a control in a dialog box. One or more of these structures are combined with a DLGTEMPLATE structure to form a standard template for a dialog box.

Syntax

    typedef struct {
        DWORD style;
        DWORD dwExtendedStyle;
        short x;
        short y;
        short cx;
        short cy;
        WORD  id;
    } DLGITEMTEMPLATE, *PDLGITEMTEMPLATE;

Members

• style
  Specifies the style of the control. This member can be a combination of window style values (such as WS_BORDER) and one or more of the control style values (such as BS_PUSHBUTTON and ES_LEFT).
• dwExtendedStyle
  Specifies extended styles for a window. This member is not used to create controls in dialog boxes, but applications that use dialog box templates can use it to create other types of windows.
• x
  Specifies the x-coordinate, in dialog box units, of the upper-left corner of the control. This coordinate is always relative to the upper-left corner of the dialog box's client area.
• y
  Specifies the y-coordinate, in dialog box units, of the upper-left corner of the control. This coordinate is always relative to the upper-left corner of the dialog box's client area.
• cx
  Specifies the width, in dialog box units, of the control.
• cy
  Specifies the height, in dialog box units, of the control.
• id
  Specifies the control identifier. Windows 95/98/Me: Only the first byte is used (that is, 255 is the maximum).

Remarks

In a standard template for a dialog box, the DLGITEMTEMPLATE structure is always immediately followed by three variable-length arrays specifying the class, title, and creation data for the control. Each array consists of one or more 16-bit elements.

Each DLGITEMTEMPLATE structure in the template must be aligned on a DWORD boundary. The class and title arrays must be aligned on WORD boundaries. The creation data array must be aligned on a WORD boundary.

Immediately following each DLGITEMTEMPLATE structure is a class array that Specifies the window class of the control. If the first element of this array is any value other than 0xFFFF, the system treats the array as a null-terminated Unicode string that specifies the name of a registered window class. If the first element is 0xFFFF, the array has one additional element that specifies the ordinal value of a predefined system class. The ordinal can be one of the following atom values.

Value Meaning 0x0080 Button 0x0081 Edit 0x0082 Static 0x0083 List box 0x0084 Scroll bar 0x0085 Combo box

Following the class array is a title array that contains the initial text or resource identifier of the control. If the first element of this array is 0xFFFF, the array has one additional element that specifies an ordinal value of a resource, such as an icon, in an executable file. You can use a resource identifier for controls, such as static icon controls, that load and display an icon or other resource rather than text. If the first element is any value other than 0xFFFF, the system treats the array as a null-terminated Unicode string that specifies the initial text.

The creation data array begins at the next WORD boundary after the title array. This creation data can be of any size and format. If the first word of the creation data array is nonzero, it indicates the size, in bytes, of the creation data (including the size word). The control's window procedure must be able to interpret the data. When the system creates the control, it passes a pointer to this data in the lParam parameter of the WM_CREATE message that it sends to the control.

If you specify character strings in the class and title arrays, you must use Unicode strings. To create code that works on both Microsoft Windows 95/98/Me and Windows NT/2000/XP, use the [MultiByteToWideChar] function to generate these Unicode strings.

The x, y, cx, and cy members specify values in dialog box units. You can convert these values to screen units (pixels) by using the MapDialogRect function.

Structure Information

• Header Declared in Winuser.h, include Windows.h
• Minimum operating systems Windows 95, Windows NT 3.1

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Notebook exported on Monday, 7 July 2008, 18:56:50 PM Eastern Daylight Time