Programming |  Windows Programming |  CHOOSECOLOR

CHOOSECOLOR

The CHOOSECOLOR structure contains information the ChooseColor function uses to initialize the Color dialog box. After the user closes the dialog box, the system returns information about the user's selection in this structure.

Syntax

    typedef struct {
        DWORD lStructSize;
        HWND hwndOwner;
        HWND hInstance;
        COLORREF rgbResult;
        COLORREF *lpCustColors;
        DWORD Flags;
        LPARAM lCustData;
        LPCCHOOKPROC lpfnHook;
        LPCTSTR lpTemplateName;
    } CHOOSECOLOR, *LPCHOOSECOLOR;

Members

• lStructSize
  Specifies the length, in bytes, of the structure.
• hwndOwner
  Handle to the window that owns the dialog box. This member can be any valid window handle, or it can be NULL if the dialog box has no owner.
• hInstance
  If the CC_ENABLETEMPLATEHANDLE flag is set in the Flags member, hInstance is a handle to a memory object containing a dialog box template. If the CC_ENABLETEMPLATE flag is set, hInstance is a handle to a module that contains a dialog box template named by the lpTemplateName member. If neither CC_ENABLETEMPLATEHANDLE nor CC_ENABLETEMPLATE is set, this member is ignored.
• rgbResult
  If the CC_RGBINIT flag is set, rgbResult specifies the color initially selected when the dialog box is created. If the specified color value is not among the available colors, the system selects the nearest solid color available. If rgbResult is zero or CC_RGBINIT is not set, the initially selected color is black. If the user clicks the OK button, rgbResult specifies the user's color selection. To create a COLORREF color value, use the RGB macro.
• lpCustColors
  Pointer to an array of 16 values that contain red, green, blue (RGB) values for the custom color boxes in the dialog box. If the user modifies these colors, the system updates the array with the new RGB values. To preserve new custom colors between calls to the ChooseColor function, you should allocate static memory for the array. To create a COLORREF color value, use the RGB macro.
• Flags
  A set of bit flags that you can use to initialize the Color dialog box. When the dialog box returns, it sets these flags to indicate the user's input. This member can be a combination of the following flags.
  • CC_ANYCOLOR
    Causes the dialog box to display all available colors in the set of basic colors.
  • CC_ENABLEHOOK
    Enables the hook procedure specified in the lpfnHook member of this structure. This flag is used only to initialize the dialog box.
  • CC_ENABLETEMPLATE
    Indicates that the hInstance and lpTemplateName members specify a dialog box template to use in place of the default template. This flag is used only to initialize the dialog box.
  • CC_ENABLETEMPLATEHANDLE
    Indicates that the hInstance member identifies a data block that contains a preloaded dialog box template. The system ignores the lpTemplateName member if this flag is specified. This flag is used only to initialize the dialog box.
  • CC_FULLOPEN
    Causes the dialog box to display the additional controls that allow the user to create custom colors. If this flag is not set, the user must click the Define Custom Color button to display the custom color controls.
  • CC_PREVENTFULLOPEN
    Disables the Define Custom Color button.
  • CC_RGBINIT
    Causes the dialog box to use the color specified in the rgbResult member as the initial color selection.
  • CC_SHOWHELP
    Causes the dialog box to display the Help button. The hwndOwner member must specify the window to receive the HELPMSGSTRING registered messages that the dialog box sends when the user clicks the Help button.
  • CC_SOLIDCOLOR
    Causes the dialog box to display only solid colors in the set of basic colors.
• lCustData
  Specifies application-defined data that the system passes to the hook procedure identified by the lpfnHook member. When the system sends the WM_INITDIALOG message to the hook procedure, the message's lParam parameter is a pointer to the CHOOSECOLOR structure specified when the dialog was created. The hook procedure can use this pointer to get the lCustData value.
• lpfnHook
  Pointer to a CCHookProc hook procedure that can process messages intended for the dialog box. This member is ignored unless the CC_ENABLEHOOK flag is set in the Flags member.
• lpTemplateName
  Pointer to a null-terminated string that names the dialog box template resource in the module identified by the hInstance member. This template is substituted for the standard dialog box template. For numbered dialog box resources, lpTemplateName can be a value returned by the MAKEINTRESOURCE macro. This member is ignored unless the CC_ENABLETEMPLATE flag is set in the Flags member.

Structure Information

• Header Declared in Commdlg.h, include Windows.h
• Minimum operating systems Windows 95, Windows NT 3.1
• Unicode Implemented as ANSI and Unicode versions.

CHOOSECOLOR cc;                 // common dialog box structure 
static COLORREF acrCustClr[16]; // array of custom colors 
HWND hwnd;                      // owner window
HBRUSH hbrush;                  // brush handle
static DWORD rgbCurrent;        // initial color selection

// Initialize CHOOSECOLOR 
ZeroMemory(&cc, sizeof(cc));
cc.lStructSize = sizeof(cc);
cc.hwndOwner = hwnd;
cc.lpCustColors = (LPDWORD) acrCustClr;
cc.rgbResult = rgbCurrent;
cc.Flags = CC_FULLOPEN | CC_RGBINIT;
 
if (ChooseColor(&cc)==TRUE) {
    hbrush = CreateSolidBrush(cc.rgbResult);
    rgbCurrent = cc.rgbResult; 
}