Re: Why does this behave the way it does?

[Kjell Ahlstedt <kjell ahlstedt bredband net>]

2012-02-29 16:16, D. R. Evans skrev:
> Oooh! That's interesting. Thank you for making things much clearer.
>
> So suppose that the bug were fixed, and also suppose that I switch to using
> a Grid instead of a Table (since if that's deprecated, they might not be
> willing to fix any bugs related to it). How would I get the Grid NOT to
> ignore those cells where nothing has been attached?
When I tested with Grid, I added two empty labels like so:

// Force the grid to contain N_ROWS x N_COLS cells
  Gtk::Label dummy1;
  Gtk::Label dummy2;
  grid.attach(dummy1, 0, 0, N_COLS, 1);  // left, top, width, height
  grid.attach(dummy2, 0, 1, 1, N_ROWS-1);  // left, top, width, height

Now I've made some more tests. I also added
  dummy1.set_size_request(SCREEN_WIDTH, SCREEN_HEIGHT/N_ROWS);
  dummy2.set_size_request(SCREEN_WIDTH/N_COLS, SCREEN_HEIGHT - 
SCREEN_HEIGHT/N_ROWS);

and all of a sudden the size is correct! This trick works also with Table.

It's probably important to have at least one widget that spans only one 
column, and one widget (not necessarily another one) that spans only one 
row. The size request routines in GtkTable (and probably also in 
GtkGrid) make a clear distinction between widgets that span a single row 
and those that span multiple rows. The same goes for single and multiple 
columns.

If you can accept one empty row and one empty column, where you attach 
empty widgets (e.g. labels) it seems you can get the table or grid size 
you want. I admit it's not very nice. With a Grid I think you must 
anyway make sure a least one widget is attached to each column, and one 
widget to each row. Ignoring empty rows and empty columns is meant to be 
a great advantage of Grid, I believe. Often it is, but not in your case.

Kjell