Re: GtkTextMark right gravity

[Darryl Ross <djr dazco com au>]

Havoc Pennington wrote:

>On Wed, Feb 05, 2003 at 02:58:49PM +1100, Darryl Ross wrote:
>  
>
>>I am trying to mark a section of text within a GtkTextBuffer and then 
>>later retrieve the text along with any changes made within the section. 
>>I have done the following:
>>
>>    /* mark the section */
>>    start_mark = gtk_text_buffer_create_mark(buffer, NULL, &iter, TRUE);
>>    gtk_text_buffer_insert(buffer, &iter, "Hello, this is some text", -1);
>>    end_mark = gtk_text_buffer_create_mark(buffer, NULL, &iter, FALSE);
>>    /* here is some more text */   
>>    gtk_text_buffer_insert(buffer, &iter, "some more text", -1);
>>
>>    /* retrieve the section */
>>    gtk_text_buffer_get_iter_at_mark(buffer, &start, start_mark);
>>    gtk_text_buffer_get_iter_at_mark(buffer, &end, end_mark);
>>    text = gtk_text_buffer_get_text(buffer, &start, &end, FALSE);
>>
>>When I get the text the "some more text" text is included if end_mark 
>>has left gravity set to false, but it is not included if end_mark has 
>>left gravity set to true. I want end_mark to be right gravity as I want 
>>insertions at the end of the section to remain within the marked section.
>>
>>    
>>
>
>If end_mark has right gravity and you insert at end_mark, then the
>inserted text should be to the left of end_mark, thus inside your
>marked section.
>
>Is the problem just how to keep "some more text" from being inside the
>section? To do that you probably have to move the end_mark after
>inserting "some more text", or create end_mark after inserting it, or
>something.
>
Thanks for the help Havoc.

Ahh, now I get it. By putting a mark with right gravity at the end of my 
text, the mark stays to the right of  the next piece of text inserted by 
my code. It's so obvious now :)

Here's my solution, just in case anyone wants to know:

    /* mark the section */
    start_mark = gtk_text_buffer_create_mark(buffer, NULL, &iter, TRUE);
    gtk_text_buffer_insert(buffer, &iter, "Hello, this is some text", -1);
    end_mark_left = gtk_text_buffer_create_mark(buffer, NULL, &iter,  TRUE);
     /* here is some more text */
    gtk_text_buffer_insert(buffer, &iter, "some more text", -1);

    /* now create a mark with right gravity at the end of the section 
(marked by end_mark_left). */
    gtk_text_buffer_get_iter_at_mark(buffer, &end_mark_iter, end_mark_left);
    end_mark = gtk_text_buffer_create_mark(buffer, NULL, &end_mark_iter, 
FALSE);

    /* retrieve the section */
    gtk_text_buffer_get_iter_at_mark(buffer, &start, start_mark);
    gtk_text_buffer_get_iter_at_mark(buffer, &end, end_mark);
    text = gtk_text_buffer_get_text(buffer, &start, &end, FALSE);

-- 
Darryl Ross
Principal Consultant, Dazco Technology ABN: 58 829 870 455
+61 3 9734 2466 http://www.dazco.com.au