how to decrease size of scrolledwindow, anybody? ... was: programatically resizing a scrolledwindow/viewport

["Karl H. Beckers" <karl h beckers gmx net>]

Hi all,

I need to make a scrolledwindow smaller but can't find a way to do it. 
It always retains its original size (unless, of course, resized 
interactively). The scrolledwindow contains a 
viewport>vbox>number_of_widgets and resides in a frame in a table in a 
dialog. I've tried out everything that seemed promising like:

before showing the dialog:

 // this is the maximum size we can have. Use this to make the dialog 
position for worst case
 gtk_widget_set_size_request( viewport1, -1, 400);

... after showing the dialog ...

 {
 // FIXME: this does not work as desired
 GtkRequisition size;
 GtkAllocation alloc;
 int set_size;

 gtk_widget_size_request(vbox2, &size);
 set_size = ( size.height > 400 ? 400 : size.height );
 alloc.x = -1;
 alloc.y = -1;
 alloc.width = size.width;
 alloc.height = set_size + 4;

 gtk_container_set_resize_mode (GTK_CONTAINER(viewport1), 
GTK_RESIZE_IMMEDIATE);
 gtk_container_set_resize_mode (GTK_CONTAINER(scrolledwindow1), 
GTK_RESIZE_IMMEDIATE);
 gtk_container_set_resize_mode (GTK_CONTAINER(frame1), 
GTK_RESIZE_IMMEDIATE);

 // actually I would like to get the right correction numbers from the 
widget, but
 // gtk_container_get_border_width always seems to return 0 ... more 
research needed.
 gtk_widget_set_size_request (viewport1, -1, ( set_size + 4 ) );
 gtk_widget_set_size_request (scrolledwindow1, -1, ( set_size + 4 ) );

 gtk_widget_set_usize(frame1, -1, ( set_size + 8 ));
 gtk_widget_set_usize(scrolledwindow1, -1, ( set_size + 8 ));
 gtk_widget_set_usize(frame1, -1, ( set_size + 8 ));

 gtk_widget_size_allocate ( viewport1, &alloc );
 gtk_widget_size_allocate ( scrolledwindow1, &alloc );
 gtk_widget_size_allocate ( frame1, &alloc );

 gtk_widget_queue_resize (viewport1);
 gtk_widget_queue_resize (scrolledwindow1);
 gtk_widget_queue_resize (frame1);
 }


TIA,

Karl.





> Hi all,
>
> in a dialog window I'm trying to have a number of widgets (each 
> represents an error) in a vbox which is contained in a scrolledwindow 
> and a viewport. When I request a minimum width for the error widgets 
> the viewport nicely calculates its width to the error widget's width 
> and thus displays it without need to scroll.
>
> This does not happen quite as nicely for height, though.
> I always get a default height of  smth. like 60 or so which isn't even 
> enough for one error widget (at a width of a couple of hundreds).
>
> Now, my desired behaviour would be: If the size of all combined error 
> widgets is less than some sensible number (e.g. 400) make the viewport 
> exactly as large. If it exceeds this value set it to the maximum and scroll. 
>
>
> I don't get real values for the vbox's height until I show the dialog. 
> This is inconvenient because if I resize the viewport from 60 to 400 
> after the window has been positioned, it's probably going to grow out 
> of the lower end of the screen.
>
> A workaround might be to first set the viewport's size to the maximum 
> value, thus causing the dialog to be positioned alright for a worst 
> case and making the viewport smaller after showing the window. 
> However, nothing I try seems to be able to make the 
> scrolledwindow/viewport smaller again.
>
> Any hints?
> Or do I have to go with a static viewport size?
>
> TIA,
>
> Karl.