Subversion Repositories Games.Chess Giants

// hyperlinks.c

#include <windows.h>

#define PROP_HYPERLINK_STRUCT L"_HyperlinkStruct"

#define PROP_HYPERLINKPARENT_STRUCT L"_HyperlinkParentStruct"

// standard hand cursor definition

#ifndef IDC_HAND

#define IDC_HAND 147

#endif

// hyperlink'ed static text control structure

typedef struct hyperlink_s

{

   HWND hWnd; // static text control window handle

   WNDPROC pfnOrigProc; // original static text control window procedure

   HFONT font; // underlined hypertext font used for this control

} hyperlink_t;

// hyperlink parent window structure

typedef struct hyperlinkparent_s

{

   HWND hWnd; // hyperlink parent window handle

   WNDPROC pfnOrigProc; // original static text control window parent procedure

} hyperlinkparent_t;

// hyperlink cursor

static HCURSOR hyperlink_cursor = NULL;

static LOGFONT hyperlink_logicalfont;

// hyperlinks.c function prototypes

void ConvertStaticToHyperlink (HWND hWndStatic);

static int WINAPI _HyperlinkParentProc (HWND hWnd, unsigned int message, WPARAM wParam, LPARAM lParam);

static int WINAPI _HyperlinkProc (HWND hWnd, unsigned int message, WPARAM wParam, LPARAM lParam);

void ConvertStaticToHyperlink (HWND hWndStatic)

{

   // subclass the parent so we can color the controls as we desire

   hyperlinkparent_t *hyperlinkparent;

   hyperlink_t *hyperlink;

   // first off, if the hand cursor isn't loaded yet, do it (this part is done once)

   if (hyperlink_cursor == NULL)

   {

      // since IDC_HAND is not available on all operating systems, we will load the arrow cursor if IDC_HAND is not present.

      hyperlink_cursor = LoadCursor (NULL, MAKEINTRESOURCE (IDC_HAND));

      if (hyperlink_cursor == NULL)

         hyperlink_cursor = LoadCursor (NULL, MAKEINTRESOURCE (IDC_ARROW)); // fallback cursor

   }

   // does this control belong to a window ?

   if (GetParent (hWndStatic) != NULL)

   {

      // mallocate space for a new hyperlink parent

      hyperlinkparent = (hyperlinkparent_t *) malloc (sizeof (hyperlinkparent_t));

      if (hyperlinkparent == NULL)

         return; // on failure, just return

      hyperlinkparent->hWnd = GetParent (hWndStatic); // save away the hyperlink parent's window handle

      hyperlinkparent->pfnOrigProc = (WNDPROC) GetWindowLong (GetParent (hWndStatic), GWL_WNDPROC); // get its current window procedure

      // has this parent NOT been already subclassed by another hyperlink ?

      if (hyperlinkparent->pfnOrigProc != (WNDPROC) _HyperlinkParentProc)

      {

         // save a pointer to the hyperlink structure in the window's properties and subclass it by replacing its window procedure by our own

         SetProp (GetParent (hWndStatic), PROP_HYPERLINKPARENT_STRUCT, (HANDLE) hyperlinkparent);

         SetWindowLongPtr (GetParent (hWndStatic), GWL_WNDPROC, (long) (WNDPROC) _HyperlinkParentProc);

      }

   }

   // mallocate space for a new hyperlink

   hyperlink = (hyperlink_t *) malloc (sizeof (hyperlink_t));

   if (hyperlink == NULL)

      return; // on failure, just return

   hyperlink->hWnd = hWndStatic; // get the static control's window handle

   hyperlink->pfnOrigProc = (WNDPROC) GetWindowLong (hyperlink->hWnd, GWL_WNDPROC); // get the static control's window procedure

   // create an updated font by adding an underline

   hyperlink->font = (HFONT) SendMessage (hyperlink->hWnd, WM_GETFONT, 0, 0);

   memset (&hyperlink_logicalfont, 0, sizeof (hyperlink_logicalfont));

   GetObject (hyperlink->font, sizeof (hyperlink_logicalfont), &hyperlink_logicalfont);

   hyperlink_logicalfont.lfUnderline = 1;

   hyperlink->font = CreateFontIndirect (&hyperlink_logicalfont);

   SendMessage (hyperlink->hWnd, WM_SETFONT, (WPARAM) hyperlink->font, 0);

   // make sure the static control will send event notifications to its window procedure

   SetWindowLong (hyperlink->hWnd, GWL_STYLE, GetWindowLong (hyperlink->hWnd, GWL_STYLE) | SS_NOTIFY);

   // save a pointer to the hyperlink structure in the window's properties and subclass it by replacing its window procedure by our own

   SetProp (hyperlink->hWnd, PROP_HYPERLINK_STRUCT, (HANDLE) hyperlink);

   SetWindowLongPtr (hyperlink->hWnd, GWL_WNDPROC, (long) (WNDPROC) _HyperlinkProc);

   return; // finished transforming the static text control

}

static int WINAPI _HyperlinkParentProc (HWND hWnd, unsigned int message, WPARAM wParam, LPARAM lParam)

{

   // this function hooks the hyperlink parent's control drawing messages so as to draw hyperlinks differently from normal static controls

   hyperlinkparent_t *hyperlinkparent;

   WNDPROC OriginalWindowProc;

   LRESULT result;

   // get a pointer to the hyperlink structure

   hyperlinkparent = (hyperlinkparent_t *) GetProp (hWnd, PROP_HYPERLINKPARENT_STRUCT);

   if (hyperlinkparent == NULL)

      return (DefWindowProc (hWnd, message, wParam, lParam)); // consistency check

   // are we drawing a static control ?

   if (message == WM_CTLCOLORSTATIC)

   {

      result = CallWindowProc (hyperlinkparent->pfnOrigProc, hWnd, message, wParam, lParam); // call the window procedure normally

      if ((WNDPROC) GetWindowLong ((HWND) lParam, GWL_WNDPROC) == (WNDPROC) _HyperlinkProc)

         SetTextColor ((HDC) wParam, RGB (0, 0, 192)); // but notify the parent to draw this text in blue if it's one of our hyperlinks

      return (result); // and return the original window proc return result

   }

   // else are we destroying ourselves ?

   else if (message == WM_DESTROY)

   {

      OriginalWindowProc = hyperlinkparent->pfnOrigProc;

      SetWindowLongPtr (hWnd, GWL_WNDPROC, (long) OriginalWindowProc); // restore the original window procedure

      if (hyperlinkparent != NULL)

         free (hyperlinkparent); // free the hyperlink parent structure

      hyperlinkparent = NULL;

      RemoveProp (hWnd, PROP_HYPERLINKPARENT_STRUCT); // and remove the window property where we used to save it

      return (OriginalWindowProc (hWnd, message, wParam, lParam)); // now call the freshly restored window procedure to let things go

   }

   // now call the original window procedure to let things go normally

   return (CallWindowProc (hyperlinkparent->pfnOrigProc, hWnd, message, wParam, lParam));

}

static int WINAPI _HyperlinkProc (HWND hWnd, unsigned int message, WPARAM wParam, LPARAM lParam)

{

   // this function hooks the messages directed to the static text control that we turned into a hyperlink

   hyperlink_t *hyperlink;

   WNDPROC OriginalWindowProc;

   // get a pointer to the hyperlink structure

   hyperlink = (hyperlink_t *) GetProp (hWnd, PROP_HYPERLINK_STRUCT);

   if (hyperlink == NULL)

      return (DefWindowProc (hWnd, message, wParam, lParam)); // consistency check

   // is the mouse moving inside the static control ?

   if (message == WM_SETCURSOR)

   {

      if (hyperlink_cursor != NULL)

         SetCursor (hyperlink_cursor); // set the static control cursor to be the pointing hand, if we have it

      return (1); // halt further processing on this message

   }

   // else are we destroying the static control ?

   else if (message == WM_DESTROY)

   {

      OriginalWindowProc = hyperlink->pfnOrigProc;

      SetWindowLongPtr (hWnd, GWL_WNDPROC, (long) OriginalWindowProc); // restore the original static control procedure

      if (hyperlink != NULL)

         free (hyperlink); // free the hyperlink structure

      hyperlink = NULL;

      RemoveProp (hWnd, PROP_HYPERLINK_STRUCT); // and remove the static control property where we used to save it

      return (OriginalWindowProc (hWnd, message, wParam, lParam)); // now call the freshly restored window procedure to let things go

   }

   // now call the original static control procedure to let things go normally

   return (CallWindowProc (hyperlink->pfnOrigProc, hWnd, message, wParam, lParam));

}