🚀 go-pugleaf

In article <1993Jan7.213019.7023@ornl.gov> woo@ornl.gov (John W. Wooten)  
writes:
> I am working on an application where I compose questions
> that will contain rich text (including diagrams).  I have a simple  
> subclass of Object called QuestionObj that I create an instance of for  
> each question and then maintain the questions in a List Object.
> 
> The text is in a text field with id "text".
> 
> I try to do the following:
> 	NXStream *buffer;
> 	
> 	count = [questions count];
> 	newQuestion = [[QuestionObj alloc] init];
> 	buffer = NXOpenMemory(NULL,0,NX_WRITEONLY);
                                    ^^^^^^^^^^^^
> 	[text writeRTFDTo:buffer];
> 	[newQuestion setText:buffer];
> 
> Now in the QuestionObj, I have:
> - setText:(NXStream *)str
> {
> 	buffer = str;
> 	return self;
> }
> - (NXStream *)text
> {
> 	return buffer;
> }
> with interface of:
> @interface QuestionObj:Object
> {
> 	int num;
> 	NXStream *buffer;
> }
> 
> - setNum:(int)val;
> - (int)num;
> - setText:(NXStream *)str;
> - (NXStream *)text;
> 
> Now, first it appears that I'm not getting the Rich Text because I  
> can't get it back out of the object with text method.

You're opening the stream as write-only.  Either open it as as read-write, or  
close the stream and have your setText method store the address of the  
buffer, rather than the stream.  To do the latter, after writing the stream,  
use NXGetMemoryBuffer() to get the address of the memory buffer that was  
created.  Use NXClose() (or NXCloseMemory() with the NX_TRUNCATEBUFFER  
option) to close the stream.  Give setText: the address of the buffer.  Then,  
when you want to read from the buffer, you can use NXOpenMemory() with the  
address of the buffer as returned by your text method.


> Also, if this even works, in the -read -write methods of the
> QuestionObj class, what do I put for the descriptor when I use
> NXWriteTypedStreamToFile ?

I don't know if you can archive a NXStream, but, if you use the second option  
I suggested, you can archive the memory buffer with NXWriteArray() with a  
type of "c".


> I used a * when it was a char * and it worked.

The "*" type is meant for strings.  It probably won't work right with memory  
buffers.

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