Mac Forum / Programming / Mac Programming / November 2004

In article
<8533bbd8ca58b1dffbce3473521f825d@localhost.talkaboutmac.com>,

Here, I've written your program for you:

On my source code web page,  <http://turbozen.com/sourcecode/>
I've put a PowerPlant project, MLTEDoc, with complete source code that
opens a RTF file into a LMLTEPane window.

Here's how you add a filter to PowerPlant's Open dialog box:

static pascal Boolean MyFilter(AEDesc *theItem, void * info, void *
/*callBackUD*/, NavFilterModes filterMode){
  switch(filterMode){
  case kNavFilteringBrowserList:
  case kNavFilteringFavorites:
  case kNavFilteringRecents:
     return CanOpen(theItem,
reinterpret_cast<NavFileOrFolderInfo*>(info));
  default:
     return true;
  }
  return false;
}

void CDocumentApp::ChooseDocument(){
  PP_StandardDialogs::LFileChooser chooser;
 
  NavDialogOptions* options = chooser.GetDialogOptions();
  if (options != nil) {
     options->dialogOptionFlags =  kNavDefaultNavDlogOptions
                             | kNavSelectAllReadableItem;
  }
  chooser.SetObjectFilterProc(MyFilter); // <- Notice
  LFileTypeList  fileTypeList(fileTypes_All);
  if(chooser.AskOpenFile(fileTypeList)){
     AEDescList     docList;
     chooser.GetFileDescList(docList);
     SendAEOpenDocList(docList);
  }
}

The complete source for "CanOpen" is in the example on my web site.
It handles the fact that Mac HFS+ filenames are really 16-bit per
character unicode, so you might like to filter by unicode suffixes.

I'll also submit it to the PowerPlant contributed class archives, but
don't hold your breath waiting for it to appear there.

I've also written a CUnicodeEditText control that is a drop in
replacement for LEditText: If you register it, instead of LEditText for
the signature 'etxt', then all your PPobs get my class instead of the
official LEditText. The advantage is that the new class uses Apple's
built in Control Manager Unicode Edit Control (not to be confused with
either MLTE or HITextView), so Unicode becomes as easy to work with for
editing as LStaticCaption makes it for static text.

I redefine GetDescriptor and SetDescriptor for my wrappers for LWindows,
and LAMControlImpl so that they assume they are working with UTF-8
strings, convert them to CFStrings, and pass them through PowerPlant's
CFString accessors. That way, all my old data files are suddenly Unicode
compatible, and even the 8-bit string manipulation in my app works right.