Re: Widget sizing?

[The Devils Jester <thedevilsjester gmail com>]

A GtkLayout does not seem to work, it seems that it does indeed request the
size of its children, so that if I put a GtkLayout inside a GtkWindow, and
I size the GtkLayout to a specific size, then I cant resize the window
smaller than that.

I have included a simple toy sample that demonstrates the issue I am
having.  If you run it, and resize the window, you cant ever make the
window smaller.

If I dont "request size" for the GtkLayout, then it is always a zero size
(or its initial size) so that any buttons or other widgets I put in it clip
immediately.  All of the children (so the layouts inside of the layouts, or
any widgets inside of those) are all sized based on the root (Window) size,
but I cant resize the root window because those widgets are all holding it
to a minimum size. I don't know what to do to solve this.  Any help solving
this would be much appreciated.

#include <gtk/gtk.h>
static void container_resize( GtkWidget *widget, GdkEvent *event, gpointer
data)
{
    gtk_widget_set_size_request((GtkWidget*)data, event->configure.width,
event->configure.height);
}

int main( int   argc, char *argv[] )
{
    gtk_init (&argc, &argv);

    // Create the Window
    GtkWidget *window;
    window = gtk_window_new (GTK_WINDOW_TOPLEVEL);

    // Create the GtkLayout child
    GtkObject* wadjust = gtk_adjustment_new(0, 0, 0, 0, 0, 0);
    GtkObject* hadjust = gtk_adjustment_new(0, 0, 0, 0, 0, 0);
    GtkWidget* layout = (GtkWidget*)
gtk_layout_new((GtkAdjustment*)wadjust, (GtkAdjustment*)hadjust);
    gtk_widget_set_size_request(layout, 500,500);
    gtk_container_add (GTK_CONTAINER (window), layout);

    // Connect to our resize function
    g_signal_connect (window, "configure-event", G_CALLBACK
(container_resize), layout);

    // Show Everything
    gtk_widget_show(layout);
    gtk_widget_show  (window);
    gtk_main ();

    return 0;
}



On Thu, Nov 13, 2014 at 1:04 PM, The Devils Jester <
thedevilsjester gmail com> wrote:

> With just a cursory glance at the containers documentation and function
> list, it seems to be exactly what I need, thank you.
>
> On Thu, Nov 13, 2014 at 12:57 PM, Tristan Van Berkom <
> tristan upstairslabs com> wrote:
>
> > On Thu, 2014-11-13 at 12:53 -0600, The Devils Jester wrote:
> > > You say that GTK has a lot of containers, are there any that already
> > > fit my needs (minimally, I am not looking for overkill).
> > >
> > >
> > > I need a container that I can add an arbitrary number of widgets to as
> > > children, and it will display these children.
> > > I don't want any styling, or layout management of any kind, I want to
> > > position/size the children as I see fit.
> > > GtkFixed fits the bill pretty nicely except that it has a "minimum
> > > size" based on the contents.
> > >
> > >
> > > Before I reinvent the wheel (or sub class the wheel!), is there an
> > > existing GTK container that can already do this?
> >
> > GtkLayout does that, but then it does not request *any* space, and
> > child widgets will simply be clipped out of the visible area unless
> > the layout is allocated enough space.
> >
> > > On Thu, Nov 13, 2014 at 12:45 PM, Tristan Van Berkom
> > > <tristan upstairslabs com> wrote:
> > >         On Thu, 2014-11-13 at 12:42 -0600, The Devils Jester wrote:
> > >         > I considered GtkContainer but my Google searches did not
> > >         come up with
> > >         > any recent examples of sub classing it and I am having a
> > >         difficult
> > >         > time understanding the mechanics behind sub classing a GTK
> > >         object.
> > >         > Does anyone have a bare bones hello world subclassed
> > >         GtkContainer
> > >         > sample that I could examine?
> > >
> > >         GTK+ has a lot of containers, my suggestion would be to pick
> > >         one
> > >         that comes close to what you want (a box perhaps ?), and start
> > >         by copying it and removing the bits that are not relevant.
> > >
> > >         The simplest cases to start with might be bin widgets like
> > >         GtkEventBox (but it does some extra stuff like creating
> > >         an extra event window).
> > >
> > >         Cheers,
> > >             -Tristan
> > >
> > >         >
> > >         > On Thu, Nov 13, 2014 at 11:34 AM, Tristan Van Berkom
> > >         > <tristan upstairslabs com> wrote:
> > >         >         On Thu, 2014-11-13 at 11:23 -0600, The Devils Jester
> > >         wrote:
> > >         >         > In a nutshell I am (more or less) trying to
> > >         simulate a
> > >         >         vertical layout
> > >         >         > manager using a GtkFixed layout manager. I have
> > >         specific
> > >         >         need to do this,
> > >         >         > rather than just use the Gtk provided one.
> > >         >
> > >         >         If you need a kind of container that GTK+ does not
> > >         provide,
> > >         >         you really
> > >         >         should just subclass GtkContainer and implement the
> > >         size
> > >         >         requesting
> > >         >         and size allocation methods.
> > >         >
> > >         >         Trying to simulate it using a GtkFixed and setting
> > >         size
> > >         >         requests might
> > >         >         seem tempting, but just wont get you what you want,
> > >         if what
> > >         >         you want
> > >         >         is content driven size allocations (you will find
> > >         yourself in
> > >         >         a catch 22
> > >         >         very quickly, where the size you previously forced
> > >         on a child
> > >         >         is
> > >         >         reported when you ask for it's new size, hence you
> > >         can never
> > >         >         know what
> > >         >         it's new requested size might be, because you
> > >         already forced
> > >         >         it
> > >         >         explicitly).
> > >         >
> > >         >         Best,
> > >         >             -Tristan
> > >         >
> > >         >         >
> > >         >         > The problem occurs when I have to resize a widget
> > >         in the
> > >         >         GtkFixed
> > >         >         > container.  The function I am using for this is
> > >         >         > gtk_widget_set_size_request.  The widget resizes
> > >         (in this
> > >         >         case it stretches
> > >         >         > to fit the "container size"), but then the window
> > >         can never
> > >         >         be resized to
> > >         >         > smaller than the widget size.   I can make the
> > >         window larger
> > >         >         (which makes
> > >         >         > the container larger, which makes the widget
> > >         larger) but I
> > >         >         can never make
> > >         >         > the window smaller because the size request holds
> > >         it to a
> > >         >         minimum size.
> > >         >         >
> > >         >         > How can I resize the widget in a way that the
> > >         window will
> > >         >         ignore its size
> > >         >         > when calculating the minimum window size?
> > >         >         > _______________________________________________
> > >         >         > gtk-app-devel-list mailing list
> > >         >         > gtk-app-devel-list gnome org
> > >         >         >
> > >         https://mail.gnome.org/mailman/listinfo/gtk-app-devel-list
> > >         >
> > >         >
> > >         >
> > >         >