🚀 go-pugleaf

In article <PSHANNON.92Dec20181421@iapetus.cv.nrao.edu>, pshannon@iapetus.cv.nrao.edu (Paul Shannon) writes:
|> I'm trying to learn more InterViews by extending the example program
|> "preview.c" so that it's more nearly a true editor.  I didn't get very
|> far in this before I got stuck on the concepts of damage and repair.
|> At least that's where I think I'm stuck.
|> 

I've had the same problem.

|> I'd like to find an explanation, and I'd like to solve this specific
|> problem:
|> 
|> void DocumentView::erase ()
|> {
|>  
|>   printf ("in DocumentView::erase   ");
|>   printf ("glyphs in buffer: %d\n", page_->count ());
|> 
|>   for (GlyphIndex i=0; i < page_->count (); i++)
|>      page_->remove (i);
|> 
|> 
|> Having removed these glyphs, what do I do to see force the screen
|> update?
|> 

I've solved the problem as follows:

DocumentView has to be derived from Patch (instead from MonoGlyph)
and an update function could be defined as

DocumentView::update() {
  page_->repair();
  reallocate();
  redraw();
}

Now you need only to call this update function in your erase function:

...
  for (GlyphIndex i=0; i < page_->count (); i++)
    page_->remove (i);

  update();
...


I hope this will help you.
-- 

==========================

Andre' Mueller
Nestler electronics GmbH
D-7630 Lahr/Schwarzwald
Tel:    +49(0)7821 284361 
E-mail: amr@nestler.DE

==========================