GTK#

Range widgets

Example

This example is a somewhat modified version of the "range controls" test from testgtk.c. It basically puts up a window with three range widgets all connected to the same adjustment, and a couple of controls for adjusting some of the parameters mentioned above and in the section on adjustments, so you can see how they affect the way these widgets work for the user.

C# example

// checkbuttons.cs - GTK# Tutorial example
//
// Authors: Alejandro Sanchez Acosta &li;raciel@es.gnu.org>
//          Cesar Octavio Lopez Nataren &li;cesar@ciencias.unam.mx>
//
// (C) 2002 Alejandro Sanchez Acosta &li;raciel@es.gnu.org>
//          Cesar Octavio Lopez Nataren &li;cesar@ciencias.unam.mx>

namespace GtkSharpTutorial {


        using Gtk;
        using GtkSharp;
        using System;
        using System.Drawing;


        public class rangeWidgetsSamples
        {
                static HScale hscale;
                static VScale vscale;
                
                static void cb_pos_menu_select (object obj, PositionType pos)
                {
                        /* Set the value position on both scale widgets */
                        ((Scale) hscale).ValuePos = pos;
                        ((Scale) vscale).ValuePos = pos;
                }

                
                static void cb_update_menu_select (object obj, UpdateType policy)
                {
                        /* Set the update policy for both scale widgets */
                        ((Range) hscale).UpdatePolicy = policy;
                        ((Range) vscale).UpdatePolicy = policy;
                }


                static void cb_digits_scale (Adjustment adj)
                {
                        /* Set the number of decimal places to which adj->value is rounded */
                        
                        /* FIXME: this might be wrong */
                        // ((Scale) hscale) = adj.Value;
                        // ((Scale) vscale) = adj.Value;
                }

                
                // FIXME
                static void cb_page_size (Adjustment get, Adjustment set)
                {
                        /* Set the page size and page increment size of the sample
                         * adjustment to the value specified by the "Page Size" scale */
                        //set.PageSize = get.Value;
                        //set->page_increment = = get.Value;

                        /* This sets the adjustment and makes it emit the "changed" signal to 
                           reconfigure all the widgets that are attached to this signal.  */
                        //set.ClampPage (                       
                }
                
                // FIXME
                static void cb_draw_value (ToggleButton button)
                {
                        /* Turn the value display on the scale widgets off or on depending
                         *  on the state of the checkbutton */
                        //((Scale) hscale).DrawValue  button.Active
                        //((Scale) vscale).DrawValue  button.Active                     
                }


                /* Convenience functions */

                // FIXME:
                static Widget make_menu_item (string name /*, callback , gpointer */)
                {
                        Widget w = null;
                        return w;
                }


                static void scale_set_default_values (Scale s)
                {
                        s.UpdatePolicy = UpdateType.Continuous;
                        s.Digits = 1;
                        s.ValuePos = PositionType.Top;
                        s.DrawValue = true;
                }

                static void create_range_controls ()
                {
                        Window window;
                        VBox box1, box3;
                        Box box2;
                        Button button;
                        HScrollbar scrollbar;
                        HSeparator separator;
                        Widget item; /* FIXME: find out the exactly widgets */
                        OptionMenu opt;
                        Menu menu;
                        Label label;
                        Scale scale;
                        Adjustment adj1, adj2;

                        window = new Window (WindowType.Toplevel);
                        // window.DeleteEvent += new DeleteEventHandler
                        window.Title = "range controls";
                        
                        box1 = new VBox (false, 0);
                        window.Add (box1);
                        box1.ShowAll ();

                        box2 = new HBox (false, 0);
                        box2.BorderWidth = 10;
                        box1.PackStart (box2, true, true, 0);
                        box2.ShowAll ();

                        /* value, lower, upper, step_increment, page_increment, page_size */
                        /* Note that the page_size value only makes a difference for
                         * scrollbar widgets, and the highest value you'll get is actually
                         * (upper - page_size). */
                        adj1 = new Adjustment (0.0, 0.0, 101.0, 0.1, 1.0, 1.0);
                        
                        vscale = new VScale ((Adjustment) adj1);
                        scale_set_default_values (vscale);
                        
                        box2.PackStart (vscale, true, true, 0);
                        vscale.ShowAll ();

                        box3 = new VBox (false, 10);
                        box2.PackStart (box3, true, true, 0);
                        box3.ShowAll ();

                        /* Reuse the same adjustment */
                        hscale = new HScale ((Adjustment) adj1);
                        hscale.SetSizeRequest (200, -1);
                        scale_set_default_values (hscale);

                        box3.PackStart (hscale, true, true, 0);
                        hscale.ShowAll ();

                        /* reuse the same adjustment again */
                        scrollbar = new HScrollbar ((Adjustment) adj1);

                        /* Notice how this causes the scales to always be updated
                         * continuously when the scrollbar is moved */
                        scrollbar.UpdatePolicy = UpdateType.Continuous;

                        box3.PackStart (scrollbar, true, true, 0);
                        scrollbar.ShowAll ();

                        box2 = new HBox (false, 10);
                        box2.BorderWidth = 10;
                        box1.PackStart (box2, true, true, 0);
                        box2.ShowAll ();

                        /* A checkbutton to control whether the value is displayed or not */
                        button = new Button ("Display value on scale widgets");
                        //FIXME
                        //((ToggleButton) button).Active = true;
                        // FIXME: find out the handler signature
                        //((ToggleButton) button).Toggled += 
                        box2.PackStart (button, true, true, 0);
                        button.ShowAll ();
                        
                        box2 = new HBox (false, 10);
                        box2.BorderWidth = 10;

                        /* An option menu to change the position of the value */
                        label = new Label ("Scale Value Position:");
                        box2.PackStart (label, false, false, 0);
                        label.ShowAll ();

                        opt = new OptionMenu ();
                        menu = new Menu ();

                        //FIXME:
                        item = new MenuItem ();
                        menu.Append (item);

                        // item =
                        menu.Append (item);
                        
                        // item = 
                        menu.Append (item);
                        
                        // item = 
                        menu.Append (item);

                        ((OptionMenu) opt).Menu = menu;
                        box2.PackStart (opt, true, true, 0);
                        opt.ShowAll ();

                        box1.PackStart (box2, true, true, 0);
                        box2.ShowAll ();
                        
                        box2 = new HBox (false, 10);
                        box2.BorderWidth = 10;

                        /* Yet another option menu, this time for the update policy of the
                         * scale widgets */
                        label = new Label ("Scale Update Policy:");
                        box2.PackStart (label, false, false, 0);
                        label.ShowAll ();

                        opt = new OptionMenu ();
                        menu = new Menu ();

                        // FIXME: continuous
                        item = new MenuItem  ();
                        menu.Append (item);

                        // FIXME: discontinuous
                        item = new MenuItem ();
                        menu.Append (item);

                        //FIXME: delayed
                        item = new MenuItem ();
                        menu.Append (item);

                        opt.Menu = menu;
                        
                        box2.PackStart (opt, true, true, 0);
                        opt.ShowAll ();

                        box1.PackStart (box2, true, true, 0);
                        box2.ShowAll ();

                        box2 = new HBox (false, 10);
                        box2.BorderWidth = 10;

                        /* An HScale widget for adjusting the number of digits on the
                         * sample scales. */
                        label = new Label ("Scale Digits:");
                        box2.PackStart (label, false, false, 0);
                        label.ShowAll ();

                        adj2 = new Adjustment (1.0, 0.0, 5.0, 1.0, 1.0, 0.0);
                        //FIXME: add a value_changed signal handler
                        scale = new HScale (adj2);
                        scale.Digits = 0;
                        
                        box2.PackStart (scale, true, true, 0);
                        scale.ShowAll ();
                        
                        box1.PackStart (box2, true, true, 0);
                        box2.ShowAll ();

                        box2 = new HBox (false, 10);
                        box2.BorderWidth = 10;

                        /* And, one last HScale widget for adjusting the page size of the
                         * scrollbar. */
                        label = new Label ("Scrollbar Page Size:");
                        box2.PackStart (label, false, false, 0);
                        label.ShowAll ();

                        adj2 = new Adjustment (1.0, 1.0, 101.0, 1.0, 1.0, 0.0);
                        // FIXME: write a value_changed signal handler
                        scale = new HScale (adj2);
                        scale.Digits = 0;
                        box2.PackStart (scale, true, true, 0);
                        scale.ShowAll ();

                        box1.PackStart (box2, true, true, 0);
                        box2.ShowAll ();

                        separator = new HSeparator ();
                        box1.PackStart (separator, false, true, 0);
                        separator.ShowAll ();
                        
                        box2 = new VBox (false, 10);
                        box2.BorderWidth = 10;
                        box1.PackStart (box2, false, true, 0);
                        box2.ShowAll ();

                        button = new Button ("Quit");
                        // FIXME: write a clicked signal handler
                        box2.PackStart (button, true, true, 0);
                        //FIXME: set widget flags
                        //FIXME: grab default
                        button.ShowAll ();

                        window.ShowAll ();                      
                }
                
                
                public static void Main (string [] args)
                {
                        Application.Init ();
                        create_range_controls ();
                        Application.Run ();
                }
        }
}


MonoBasic example