HelpBox.cs

   1 using System.Collections;
   2 using System.IO;
   3 using System;
   4 using Cairo;
   5 using Pango;
   6
   7 public struct HelpItem {
   8         public string Key;
   9         public string Text;
  10
  11         public HelpItem(string key, string text) {
  12                 Key = key;
  13                 Text = text;
  14         }
  15
  16         public override string ToString() {
  17                 return "<b>" + Key + "</b>\t" + Text;
  18         }
  19 }
  20
  21 public class HelpBox {
  22         private Pango.Context pc;
  23         private Pango.FontDescription titleFont;
  24         private Pango.FontDescription textFont;
  25         private string helpTitle;
  26         private HelpItem[] helpText;
  27         private int Width = 480;
  28         private int Height = 360;
  29         private int Columns = 3;
  30
  31         public HelpBox(Pango.Context pc, string title, HelpItem[] items) {
  32                 this.pc = pc;
  33                 helpTitle = title;
  34                 helpText = items;
  35                 init();
  36         }
  37
  38         public HelpBox(Pango.Context pc, string filename) {
  39                 StreamReader file = new StreamReader(filename);
  40                 string line;
  41                 ArrayList items = new ArrayList();
  42
  43                 this.pc = pc;
  44                 helpTitle = file.ReadLine();
  45                 while ((line = file.ReadLine()) != null) {
  46                         string[] i = line.Split(null, 2);
  47                         if (i.Length == 2) {
  48                                 items.Add(new HelpItem(i[0], i[1]));
  49                         }
  50                 }
  51                 helpText = new HelpItem[items.Count];
  52                 for (int i = 0; i < items.Count; i++) {
  53                         helpText[i] = (HelpItem) items[i];
  54                 }
  55                 init();
  56         }
  57
  58         private void init() {
  59                 titleFont = Pango.FontDescription.FromString("Helvetica Bold 24");
  60                 textFont = Pango.FontDescription.FromString("Helvetica 16");
  61                 Pango.FontMetrics fmTitle = pc.GetMetrics(titleFont, null);
  62                 Pango.FontMetrics fmText = pc.GetMetrics(textFont, null);
  63                 int hTitle = Pango.Units.ToPixels(fmTitle.Ascent + fmTitle.Descent);
  64                 int hText = Pango.Units.ToPixels(fmText.Ascent + fmText.Descent);
  65
  66                 Width = 480;
  67                 for (int i = 0; i < helpText.Length; i++) {
  68                         Pango.Layout layout = new Pango.Layout(pc);
  69                         Pango.Rectangle r, r2;
  70
  71                         layout.FontDescription = textFont;
  72                         layout.SetMarkup(helpText[i].ToString());
  73                         layout.GetExtents(out r, out r2);
  74                         int pw = Pango.Units.ToPixels(r2.Width);
  75                         if ((pw + 8) * Columns > Width) {
  76                                 Width = (pw + 8) * Columns;
  77                         }
  78                 }
  79                 Height = hTitle + (helpText.Length / 3 + 1) * hText + 12;
  80         }
  81
  82         public void draw(Cairo.Context gr, int width, int height) {
  83                 Pango.Layout layout;
  84                 Cairo.Rectangle r = new Cairo.Rectangle(
  85                         width / 2 - Width / 2,
  86                         height / 2 - Height / 2,
  87                         Width, Height);
  88
  89                 gr.SetSourceRGBA(1.0, 1.0, 1.0, 0.8);
  90                 gr.NewPath();
  91                 gr.Rectangle(r);
  92                 gr.Fill();
  93
  94                 gr.SetSourceRGB(0.0, 0.0, 0.0);
  95                 gr.NewPath();
  96                 gr.Rectangle(r);
  97                 gr.Stroke();
  98
  99                 gr.MoveTo(r.X + 4, r.Y + 4);
 100                 layout = new Pango.Layout(pc);
 101                 layout.SetText(helpTitle);
 102                 layout.Width = Pango.Units.FromPixels((int)r.Width);
 103                 layout.FontDescription = titleFont;
 104                 Pango.CairoHelper.ShowLayout(gr, layout);
 105
 106                 int ii = 0;
 107                 int ColumnWidth = Width / Columns;
 108                 int ColumnLines = helpText.Length / Columns + 1;
 109                 for (int i = 0; i < Columns; i++) {
 110                         gr.MoveTo(r.X + 4 + (i * ColumnWidth), r.Y + 38);
 111                         string column = "";
 112                         for (int j = 0; j < ColumnLines && ii < helpText.Length; j++) {
 113                                 column += helpText[ii].ToString() + "\n";
 114                                 ii++;
 115                         }
 116                         layout = new Pango.Layout(pc);
 117                         layout.SetMarkup(column);
 118                         layout.Width = Pango.Units.FromPixels(ColumnWidth);
 119                         layout.FontDescription = textFont;
 120                         Pango.CairoHelper.ShowLayout(gr, layout);
 121                 }
 122         }
 123 }