spider-web/MultiLineLabel.java

   1 import java.awt.*;
   2 import java.util.*;
   3
   4 public class MultiLineLabel extends Canvas {
   5         public static final int LEFT = 0;
   6         public static final int CENTER = 1;
   7         public static final int RIGHT = 2;
   8         protected String[] lines;
   9         protected int num_lines;
  10         protected int margin_width;
  11         protected int margin_height;
  12         protected int line_height;
  13         protected int line_ascent;
  14         protected int[] line_widths;
  15         protected int max_width;
  16         protected int alignment = LEFT;
  17
  18         protected void newLabel(String label) {
  19                 StringTokenizer t = new StringTokenizer(label,"\n");
  20                 num_lines = t.countTokens();
  21                 lines = new String[num_lines];
  22                 line_widths = new int[num_lines];
  23                 for(int i = 0; i < num_lines; i++) lines[i] = t.nextToken();
  24         }
  25
  26         protected void measure() {
  27                 FontMetrics fm = this.getFontMetrics(this.getFont());
  28                 if (fm == null) return;
  29
  30                 line_height = fm.getHeight();
  31                 line_ascent = fm.getAscent();
  32                 max_width = 0;
  33                 for(int i = 0; i < num_lines; i++) {
  34                         line_widths[i] = fm.stringWidth(lines[i]);
  35                         if (line_widths[i] > max_width) max_width = line_widths[i];
  36                 }
  37         }
  38
  39         public MultiLineLabel(String label, int margin_width,
  40                int margin_height, int alignment) {
  41                 newLabel(label);
  42                 this.margin_width = margin_width;
  43                 this.margin_height = margin_height;
  44                 this.alignment = alignment;
  45         }
  46
  47         public MultiLineLabel(String label, int margin_width, int margin_height) {
  48                 this(label, margin_width, margin_height, LEFT);
  49         }
  50
  51         public MultiLineLabel(String label, int aligment) {
  52                 this(label, 10, 10, aligment);
  53         }
  54
  55         public MultiLineLabel(String label) {
  56                 this(label, 10, 10, LEFT);
  57         }
  58
  59         public void setLabel(String label) {
  60                 newLabel(label);
  61                 measure();
  62                 repaint();
  63         }
  64
  65         public void setFont(Font f) {
  66                 super.setFont(f);
  67                 measure();
  68                 repaint();
  69         }
  70
  71         public void setForegroundColor(Color c) {
  72                 super.setForeground(c);
  73                 repaint();
  74         }
  75
  76         public void setAligment(int a) { alignment = a; repaint(); }
  77         public void setMarginWidth(int mw) { margin_width = mw; repaint(); }
  78         public void setMarginHeight(int mh) { margin_height = mh; repaint(); }
  79         public int getAlignment() { return alignment; }
  80         public int getMarginWidth() { return margin_width; }
  81         public int getMarginheight() { return margin_height; }
  82
  83         public void addNotify() { super.addNotify(); measure(); }
  84
  85         public Dimension preferedSize() {
  86                 return new Dimension(max_width + 2 * margin_width,
  87                                      num_lines * line_height + 2 * margin_height);
  88         }
  89
  90         public Dimension miniumSize() {
  91                 return new Dimension(max_width, num_lines * line_height);
  92         }
  93
  94         public void paint(Graphics g) {
  95                 int x,y;
  96                 Dimension d = this.size();
  97                 y = line_ascent + (d.height - num_lines * line_height) / 2;
  98                 for(int i = 0; i < num_lines; i++, y += line_height) {
  99                         switch(alignment) {
 100                                 case LEFT:
 101                                         x = margin_width; break;
 102                                 case CENTER:
 103                                 default:
 104                                         x = (d.width - line_widths[i]) / 2; break;
 105                                 case RIGHT:
 106                                         x = d.width - margin_width - line_widths[i]; break;
 107                         }
 108                         g.drawString(lines[i], x, y);
 109                 }
 110         }
 111 }