src/KnobWithDisplay.vala

   1 /*
   2     Copyright 2009 by Hans Baier
   3     License: LGPLv2+
   4 */
   5
   6 using Gtk;
   7
   8 namespace Prolooks {
   9
  10 public class KnobWithDisplay : EventBox {
  11     private Box vbox;
  12     private Knob knob;
  13     private ValueDisplay display;
  14
  15     public string unit { get; set; }
  16
  17     // This function is called whenever the knob value changes
  18     public delegate void DisplayFunc (Knob knob, ValueDisplay display, KnobWithDisplay knob_with_display);
  19
  20     private DisplayFunc? display_func = null;
  21     public void set_display_func (DisplayFunc func) {
  22         display_func = func;
  23     }
  24
  25     // delegating properties
  26     [Description(nick="show matrix", blurb="Whether a pixel matrix should be drawn in the display background (much faster if false)")]
  27     public bool show_matrix       { get { return display.show_matrix;    } set { display.show_matrix = value; } }
  28     public Adjustment adjustment  { get { return knob.get_adjustment (); } set { knob.set_adjustment (value); } }
  29     [Description(nick="knob mode", blurb="determines, how the knob will work / look like")]
  30     public KnobMode knob_mode     { get { return knob.knob_mode;         } set { knob.knob_mode = value;      } }
  31     [Description(nick="decimal places", blurb="The value will be rounded to the given number of decimal places")]
  32     public uint  decimal_places   { get { return knob.decimal_places;    } set { knob.decimal_places = value; } }
  33
  34     construct {
  35         vbox = new Box (Gtk.Orientation.VERTICAL, 0);
  36         knob = new Knob ();
  37         vbox.pack_start (knob);
  38         display = new ValueDisplay ();
  39         vbox.pack_start (display);
  40         knob.user_data = display;
  41                 decimal_places = 2;
  42         var adj = knob.get_adjustment ();
  43         knob.value_changed += (knob) => {
  44             ValueDisplay disp = knob.user_data as ValueDisplay;
  45             string text;
  46
  47             if (display_func != null) {
  48                 display_func (knob, display, this);
  49             } else {
  50                 text = "%.*f".printf (knob.decimal_places, knob.get_value ()) + " " + unit;
  51                 disp.text = text;
  52             }
  53         };
  54
  55         add (vbox);
  56         show_matrix = true;
  57         GLib.Timeout.add (512, ()=> {
  58             knob.value_changed ();
  59         });
  60     }
  61 }
  62
  63 } // namespace Prolooks
  64