The Static Class

You create static child window controls by using "static" as the window class in the CreateWindow function. These are fairly benign child windows. They do not accept mouse or keyboard input, and they do not send WM_COMMAND messages back to the parent window.

When you move or click the mouse over a static child window, the child window traps the WM_NCHITTEST message and returns a value of HTTRANSPARENT to Windows. This causes Windows to send the same WM_NCHITTEST message to the underlying window, which is usually the parent. The parent usually passes the message to DefWindowProc, where it is converted to a client-area mouse message.

The first six static window styles simply draw a rectangle or a frame in the client area of the child window. The "RECT" static styles (left column below) are filled-in rectangles; the three "FRAME" styles (right column) are rectangular outlines that are not filled in.

SS_BLACKRECT	SS_BLACKFRAME
SS_GRAYRECT	SS_GRAYFRAME
SS_WHITERECT	SS_WHITEFRAME

"BLACK," "GRAY," and "WHITE" do not mean the colors are black, gray, and white. Rather, the colors are based on system colors, as shown here:

Static Control	System Color
BLACK	COLOR_3DDKSHADOW
GRAY	COLOR_BTNSHADOW
WHITE	COLOR_BTNHIGHLIGHT

The window text field of the CreateWindow call is ignored for these styles. The upper left corner of the rectangle begins at the x position and y position coordinates relative to the parent window. You can also use the SS_ETCHEDHORZ, SS_ETCHEDVERT, or SS_ETCHEDFRAME styles to create a shadowed-looking frame with the white and gray colors.

The static class also includes three text styles: SS_LEFT, SS_RIGHT, and SS_CENTER. These create left-justified, right-justified, and centered text. The text is given in the window text parameter of the CreateWindow call, and it can be changed later using SetWindowText. When the window procedure for static controls displays this text, it uses the DrawText function with DT_WORDBREAK, DT_NOCLIP, and DT_EXPANDTABS parameters. The text is wordwrapped within the rectangle of the child window.

The background of these three text-style child windows is normally COLOR_BTNFACE, and the text itself is COLOR_WINDOWTEXT. You can intercept WM_CTLCOLORSTATIC messages to change the text color by calling SetTextColor and the background color by calling SetBkColor and by returning the handle to the background brush. This will be demonstrated in the COLORS1 program shortly.

Finally, the static class also includes the window styles SS_ICON and SS_USERITEM. However, these styles have no meaning when they are used as child window controls. We'll look at them again when we discuss dialog boxes.