Symantec Top 10

This monthly column, written by Symantec’s Technical Support Engineers, aims to provide you with technical information based on the use of Symantec products.

By Craig Conner

This month, we are going to answer some questions about using the TCL class CStyleText with Visual Architect. A project demonstrating CStyleText is available on either CompuServe or America Online, or on ftp.devtools.symantec.com.

Q: How do I create a CStyleText pane in Visual Architect?

A: Since this class does not appear in the VA Base Class popup in the Classes dialog you cannot override it in the standard way. You can, however, create a class based on CEditText and use CStyleText as a Library Class.

To review how library classes work: Usually, VA produces x_class classes derived from the class specified in the Base Class popup menu. When you use a Library Class, VA bases the x_class on the library class and assumes the library class is derived from the base class.

Creating a class in this fashion causes VA to generate an x_class derived from CStyleText, which in turn is based on CEditText, so everything is right with the world. You can then assign this class to a panorama created with the normal panorama tool, not the EditText-like tool, which is actually a CDialogText pane.

Note: For the rest of this article, I will refer to this view with the name TextPane (real original, huh?) and the class as CStyledTextEditPano, for short. I also call the document class CStyledDoc, and the application class CStyleApp.

Q: I have problems aligning the pane into the window correctly. What is the best way to set this up?

A: The easy way to set up a pane or panorama to completely cover a window is to adjust the bounds using the edit boxes. You will want to overlap the pane one pixel on each side. For example, when I look in the View Info dialog for my project, it lists the Width as 471 and Height as 443. So my CStyleText panorama is positioned at (-1, -1), and has a Width of 473 and a Height of 445.

Q: How do I set up the Font, Style and Size menus?

A: The Add Menu popup for the Menu Bar dialog box contains pre-created Font, Size and Style menus. Add these menus to the current menu bar. The Style menu has commands associated with each menu item, so TCL will take care of changing styles for the current selection. Both the default Font and Size menus are empty, so we will have to add items programmatically.

To add items we must override CApplication::SetUpMenus(), and then we revert to standard Macintosh Toolbox practices to add items. For example:

 void CStyleApp::SetUpMenus()
{
    // To handle standard initialization.
 CApplication::SetUpMenus();

    // Add the system fonts the standard way
 AddResMenu(GetMHandle(MENUfont), 'FONT');

 MenuHandle sizeMenuH = GetMHandle(MENUsize);

    // I’ve got other things planned, so we might as well 
    // account for that possibility now
 short numItems = CountMItems(sizeMenuH);

 InsMenuItem(sizeMenuH, "\p9", numItems + 1);
 
    // Similarly for other sizes...

    // Now deal with keeping items highlighted and uncheck all items   
    // when Update menus called for ease of dealing with at that time.
 gBartender -> SetDimOption(MENUfont, dimNone);
 gBartender -> SetUnchecking(MENUfont, TRUE);

    // do the same for MENUsize and MENUstyle...
}

These Font and Style menus do not have commands
associated with them because of the generic way TCL handles font and size changes. Look in CAbstractText::DoCommand() and CTextStyleTask::Do() for more information.

Having added and configured the menus, we now have to handle checking the correct menu item when the menus are displayed. We do this in the CStyledDoc::UpdateMenus(), like so:

CStyledDoc::UpdateMenus()
{
 short whichAttributes = doFont | doSize | doFace;
 TextStyle theStyle;
 Str255 itemString;
 short fontNumber;
 long fontSize;
 short count;
 
 inherited::UpdateMenus();
 
 MenuHandle fontMenu = GetMHandle(MENUfont);
 count = CountMItems(fontMenu);
 
 for (int n = 1; n <= count; n++)
 {
 GetItem(fontMenu, n, itemString);
 GetFNum(itemString, &fontNumber);
 
 if(fontNumber == theStyle.tsFont)
 CheckItem(fontMenu, n, TRUE);
 }

 
 MenuHandle sizeMenu = GetMHandle(MENUsize);
 count = CountMItems(sizeMenu);
 
 for (n = 3; n <= count; n++)
 {
 GetItem(sizeMenu, n, itemString);
 StringToNum(itemString, &fontSize);
 
 if(fontSize == theStyle.tsSize)
 CheckItem(sizeMenu, n, TRUE);
 }

    // handle easy case first
 if (theStyle.tsFace == normal)
 gBartender->CheckMarkCmd(cmdPlain, TRUE);
 else
 {
    // Turn on the correct ones
 if(theStyle.tsFace & bold)
 gBartender->CheckMarkCmd(cmdBold, TRUE);
 
    // similarly for italic, underline, etc.
 } 
}

Q: What happens if I want to use a different font size than what is in the menu?

A. Well, we can add an Other menu item to the Size menu in VA, and for correctness there should be a line between this item and the font sizes, so add one of those too. These need to be at the top of the menu, so TCL does not lose track of where it is in the menu. (All items with commands need to appear in menus before items without commands associated with them.)

Create a modal dialog view that has a DialogText item in it, so we can have the user enter the size. The item should be set to be of type CIntegerText. You should also set a range in the Pane Info dialog under CIntegerText, for example from 4 to 256. Also check the showRangeOnErr checkbox to inform the user if they make a mistake. (It’s the Macintosh Way.)

Now to complete the VA part of this, create a cmdOtherSize and associate it with the Other menu item. Have the command generate code to open the newly created dialog in the CStyleText derived class.

Next, we have to add code to handle the size change. We add this to an override of ProviderChanged() in CStyledTextEditPano:

 if(reason == kFontSizeDialogEnding)
 {
 long size;
 size = ((CFontSizeDialogData *)info)
  -> fPointSizeDialog_PointSizeEditText;
 
    // To fake out the CStyleText operations and handle a 
    // non-menu item size, we throw a new item into the menu and
    // call the command, then delete menu item
 long theCmd = (MENUsize << 16) + 3;
 Str255 string;
 
 NumToString(size, string);
 gBartender->InsertMenuCmd
 (theCmd, string, MENUsize, 2);
 
    // negate the command, so TCL knows it does not have an
    // associated command and send it.
 DoCommand(-theCmd);

 gBartender->RemoveMenuCmd(theCmd);
 }
 else
 inherited::ProviderChanged(aProvider,reason,info);

Q: After generating and compiling, why isn’t the cursor in the pane when I open a view?

A: Currently, the gopher is assigned to theMainPane of the window. To associate the gopher with the style text pane, we can re-assign it:

       
       itsGopher = fTextPane_StyleTextPano;

Do this at the end of CStyleDoc::ContentsToWindow().

Q: How do I save and read in a styled text document?

A: Saving a styled text document requires saving the text, and saving the style of that text. An easy way to do this is to use the CSimpleSaver class. In VA, make CSimpleSaver a library class for CStyledDoc. You will also need to override ReadContents() and WriteContents() (they can have empty bodies) in CStyledDoc to complete the class definition.

You can save the text using the CDataFile object member of CStyledDoc, itsFile. To save the style of the text, we need to save it into a 'styl' resource with the ID number 128. This is the standard location for style information. To save into the resource you can create a CResFile object.

Add something like this to

CStyledDoc::ContentsToWindow():

 if(itsFile)
 {
    // Deal with the text first
 Handle text = 
 fTextPane_StyleTextPano->GetTextHandle();
 ((CDataFile *)itsFile)->WriteAll(text);
 
    // And now deal with the style info
 FSSpec theSpec;

 itsFile->GetFSSpec(&theSpec);
 
 CResFile theResFile;
 
 theResFile.SpecifyFSSpec(&theSpec);

 if(!theResFile.HasResFork())
 theResFile.CreateNew('ttxt','TEXT');

 theResFile.Open(fsRdWrPerm);
 
 Handle theStyle, newStyle;
 
 theStyle = GetResource('styl', 128);
 
    // as per IM:Text p. 2-52 with a little TCL thrown in
 long savedStart, savedEnd;

 fTextPane_StyleTextPano->
 GetSelection(&savedStart, &savedEnd);
 
 (*fTextPane_StyleTextPano->macTE)->selStart = 0;
 (*fTextPane_StyleTextPano->macTE)->selEnd = 
 fTextPane_StyleTextPano->GetLength();
 
 newStyle = (Handle)fTextPane_StyleTextPano ->
 GetTheStyleScrap();
 
 (*fTextPane_StyleTextPano->macTE)->selStart =
 savedStart;
 (*fTextPane_StyleTextPano->macTE)->selEnd =
 savedEnd;
 
 HLock(theStyle);
 HLock(newStyle);
 
 if(theStyle)
 {
 long len = GetHandleSize(newStyle);
 
 SetHandleSize(theStyle, len);

 BlockMove(*newStyle, *theStyle, len);
 
 ChangedResource((Handle)theStyle);
 WriteResource(theStyle);
 }
 else
 {
 AddResource(
 newStyle , 'styl', 128, "\ptext style"
 );
 WriteResource(newStyle);
 }

 HUnlock(theStyle);
 HUnlock(newStyle);
 
 theResFile.Update();
 }

Reading in a styled text document is basically the reverse of this, and left as an exercise for the reader.

Q: Why does the application crash when I try to open a currently open document?

A: In x_CStyledDoc::FailOpen(), you will see that it calls Failure() if the file is already open. You will want to override FailOpen() to open a dialog or otherwise handle the situation.

Q: How do I get the document to print?

A: TCL has code to handle this for you. Make sure you have the Print checkbox checked in the View Info dialog for the main window.

Q: When I print, why does it cut lines in half at the bottom of the page?

A: You have the fixedLineHeights checkbox checked in the Pane Info for the StyledText panorama. (I did not tell you to turn it off earlier because I would then have only nine questions.) Uncheck that and TCL will handle printing styled text correctly.

Q: When there is no current selection, changing the Font, Size, or Style menus do not affect what I type next. Why not?

A: TCL relies on the style of the current selection to set the menus when that information is needed. To change this behavior we need to create a data member of type TextStyle for our CStyledTextEditPano to save the menu choices. I called it theStyle. Then we need to save this information:

void CStyledTextEditPano::
 DoKeyDown(
 char theChar, Byte keyCode, EventRecord *macEvent
 )
{
 long selStart, selEnd;
 
 CStyleText::GetSelection(&selStart,&selEnd);
 
// The case we want to change behavior of
 if(selStart == selEnd)
 {
 short whichAttributes = doFont | doSize | doFace;
 GetTextStyle(&whichAttributes, &theStyle);
 }
 
 inherited::DoKeyDown(theChar, keyCode, macEvent);
}

and restore the correct style:

void CStyledTextEditPano::TypeChar(
 char theChar, short theModifers
)
{
 short whichAttributes = doFont | doSize | doFace;
 
 TESetStyle(
 whichAttributes, &theStyle, FALSE, macTE
 );
 
 inherited::TypeChar(theChar, theModifers);
}