GrayString

GrayString

The GrayString function draws gray text at the specified location. The function draws the text by copying it into a memory bitmap, graying the bitmap, and then copying the bitmap to the screen. The function grays the text regardless of the selected brush and background. GrayString uses the font currently selected for the specified device context.

If the lpOutputFunc parameter is NULL, GDI uses the TextOut function, and the lpData parameter is assumed to be a pointer to the character string to be output. If the characters to be output cannot be handled by TextOut (for example, the string is stored as a bitmap), the application must supply its own output function.

BOOL GrayString(

HDC hDC,	// handle to the device context
HBRUSH hBrush,	// handle to the brush for graying
GRAYSTRINGPROC lpOutputFunc,	// pointer to the callback function
LPARAM lpData,	// pointer to application-defined data
int nCount,	// number of characters to output
int X,	// horizontal position
int Y,	// vertical position
int nWidth,	// width
int nHeight	// height
);

Parameters

hDC

Identifies the device context.

hBrush

Identifies the brush to be used for graying. If this parameter is NULL, the text is grayed with the same brush that was used to draw window text.

lpOutputFunc

Points to the application-defined function that will draw the string, or, if TextOut is to be used to draw the string, it is a NULL pointer. For details, see the OutputProc callback function.

lpData

Specifies a pointer to data to be passed to the output function. If the lpOutputFunc parameter is NULL, lpData must be a pointer to the string to be output.

nCount

Specifies the number of characters to be output. If the nCount parameter is zero, GrayString calculates the length of the string (assuming lpData is a pointer to the string). If nCount is -1 and the function pointed to by lpOutputFunc returns FALSE, the image is shown but not grayed.

Specifies the device x-coordinate of the starting position of the rectangle that encloses the string.

Specifies the device y-coordinate of the starting position of the rectangle that encloses the string.

nWidth

Specifies the width, in device units, of the rectangle that encloses the string. If this parameter is zero, GrayString calculates the width of the area, assuming lpData is a pointer to the string.

nHeight

Specifies the height, in device units, of the rectangle that encloses the string. If this parameter is zero, GrayString calculates the height of the area, assuming lpData is a pointer to the string.

Return Values

If the string is drawn, the return value is nonzero.

If either the TextOut function or the application-defined output function returned zero, or there was insufficient memory to create a memory bitmap for graying, the return value is zero.

Remarks

Without calling GrayString, an application can draw grayed strings on devices that support a solid gray color. The system color COLOR_GRAYTEXT is the solid-gray system color used to draw disabled text. The application can call the GetSysColor function to retrieve the color value of COLOR_GRAYTEXT. If the color is other than zero (black), the application can call the SetTextColor function to set the text color to the color value and then draw the string directly. If the retrieved color is black, the application must call GrayString to gray the text.