fix list boxes with a temporary hack to access the 'ldes' resource from the Finder

widget/src/mac/nsListBox.cpp

@@ -19,6 +19,8 @@
 #include "nsListBox.h"
 #include <StringCompare.h>
 #include <Resources.h>
+#include <Folders.h>
+#include <LowMem.h>
 #if TARGET_CARBON
 #include <ControlDefinitions.h>
 #endif
@@ -92,26 +94,68 @@ NS_IMETHODIMP nsListBox::Create(nsIWidget *aParent,
                       nsIToolkit *aToolkit,
                       nsWidgetInitData *aInitData) 
 {
-	Handle resH = ::NewHandleClear(sizeof(ldesRsrc));
-	if (resH)
-	{
-		ldesRsrc** ldesH = (ldesRsrc**)resH;
-		(*ldesH)->cols = 1;
-		(*ldesH)->vertScroll = 1;
-		short resID = mValue = 2222;
-		::AddResource(resH, 'ldes', resID, "\p");
+		short			sysVRefNum;
+		long			sysDirID;
+		short			fRefNum;
+		short			saveResFile;
+		Handle		resH;
+
+	#define kFinderLDESRsrcID 128
+
+	{	//---
+		// Hack: the list control needs a 'ldes' resource to initialize properly but
+		// we don't have any global resource file that we could use to store one as a 
+		// resource template so we temporarily borrow the resource that exists in the Finder.
+		//
+		//¥REVISIT: this hack is probably a big performance hit because the Finder rsrc fork
+		// is accessed each time a list box is created. Amongst possible solutions:
+		//	- Switch to GFX widgets. Problem: maybe we'll still want to keep the native widgets.
+		//	- Define a Mozilla resource file that all the applications (internal + embedding)
+		//		will have to include. Problem: risk of rsrc ID conflicts with embedding apps.
+		//	- Keep this hack but have a global refNum for the Finder. Problem: well...
+		//	- Stop using the Appearance Manager control for list boxes: use LNew directly.
+		saveResFile = ::CurResFile();
+		::FindFolder(kOnSystemDisk, kSystemFolderType, kDontCreateFolder, &sysVRefNum, &sysDirID);
+		fRefNum = HOpenResFile(sysVRefNum, sysDirID, ::LMGetFinderName(), fsRdPerm);
+		if (fRefNum != -1)
+		{
+			::UseResFile(fRefNum);
+
+			resH = ::GetResource(kControlListDescResType, kFinderLDESRsrcID);
+			if (resH)
+			{
+				ldesRsrc** ldesH = (ldesRsrc**)resH;
+				(*ldesH)->version 		= 0;
+				(*ldesH)->rows 				= 0;
+				(*ldesH)->cols 				= 1;
+				(*ldesH)->cellHeight 	= 0;
+				(*ldesH)->cellWidth 	= 0;
+				(*ldesH)->vertScroll 	= 1;
+				(*ldesH)->horizScroll	= 0;
+				(*ldesH)->ldefID 			= 0;
+				(*ldesH)->hasGrow 		= 0;
+			}
+		}
 	}
 
+	mValue = kFinderLDESRsrcID;
 	nsresult res = Inherited::Create(aParent, aRect, aHandleEventFunction,
 						aContext, aAppShell, aToolkit, aInitData);
-	if (resH)
-	{
-		::RemoveResource(resH);
-		::DisposeHandle(resH);
+
+	{	//---
+		// Hack: part 2 - see above
+		if (fRefNum != -1)
+		{
+			if (resH)
+				::ReleaseResource(resH);
+
+			::CloseResFile(fRefNum);
+			::UseResFile(saveResFile);
+		}
 	}
 
-  	if (res == NS_OK)
-  	{
+	if (res == NS_OK)
+	{
 		Size actualSize;
 		::GetControlData(mControl, kControlNoPart, kControlListBoxListHandleTag, sizeof(ListHandle), (Ptr)&mListHandle, &actualSize);
 		if (mListHandle)
@@ -123,8 +167,8 @@ NS_IMETHODIMP nsListBox::Create(nsIWidget *aParent,
 			::LSetDrawingMode(mVisible, mListHandle);
 		}
 		else
-  			res = NS_ERROR_FAILURE;
-  	}
+			res = NS_ERROR_FAILURE;
+	}
 
 	return res;
 }