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1
6
7 package com.quikj.application.web.talk.client.whiteboard;
8
9 import java.awt.*;
10 import java.awt.event.*;
11 import java.util.*;
12
16 public class WhiteBoardCanvas extends java.awt.Canvas 
17 {
18 public static final int MODE_LINE = 0;
19 public static final int MODE_TEXT = 1;
20 public static final int MODE_ERASER = 2;
21 public static final int MODE_FREEHAND = 3;
22 public static final int MODE_RECTANGLE = 4;
23 public static final int MODE_OVAL = 5;
24
25 private int mode = MODE_FREEHAND;
26 private Vector objects = new Vector();
28 private Vector freehandVector;
30
31 private Point lineStartPoint = null;
33 private Point lineEndPoint = null;
34
35 private StringBuffer textBuffer;
37 private Point textStartPoint;
38 private boolean textCursorVisible = false;
39 private Point textCursorPosition;
40
41 private Vector eraserVector;
43
44 private Point rectangleStartPoint;
46 private Rectangle rectangle = null;
47
48 private Point ovalStartPoint;
50 private Rectangle oval = null;
51
52 ObjectListenerInterface listener = null;
53
54
55 public WhiteBoardCanvas()
56 {
57 setDefaultCursor();
58 addMouseListener(new MouseListener());
59 addMouseMotionListener(new MouseMotionListener());
60 addKeyListener(new KeyListener());
61 }
62
63 public void paint(java.awt.Graphics graphics)
64 {
65 graphics.setPaintMode();
66
67 graphics.clearRect(0, 0, getBounds().width, getBounds().height);
68
69 int size = objects.size();
70 for (int i = 0; i < size; i++)
71 {
72 ((WhiteBoardObjectInterface)objects.elementAt(i)).draw();
73 }
74
75 if (mode == MODE_TEXT)
77 {
78 if (textBuffer != null)
79 {
80 if (textBuffer.length() > 0)
81 {
82 graphics.setXORMode(Color.gray);
83 graphics.drawString(textBuffer.toString(),
84 textStartPoint.x, textStartPoint.y);
85 FontMetrics fm = graphics.getFontMetrics();
86 graphics.drawRect(textCursorPosition.x, textCursorPosition.y,
87 fm.charWidth('w'), fm.getHeight());
88 }
89 }
90 }
91 }
92
93 public void setMode(int mode)
94 {
95 if (this.mode == MODE_TEXT)
96 {
97 completeText();
98 }
99
100 this.mode = mode;
101 setDefaultCursor();
102 }
103
104 public int getMode()
105 {
106 return mode;
107 }
108
109 private void setDefaultCursor()
110 {
111 setCursor(Cursor.getPredefinedCursor(Cursor.HAND_CURSOR));
112 }
113
114 public void removeLastObject()
115 {
116 if (objects.size() > 0)
117 {
118 objects.removeElementAt(objects.size() - 1);
119 repaint();
120 }
121 }
122
123 private void drawRectangle(Graphics graphics)
124 {
125 if (rectangle != null)
126 {
127 if ((rectangle.width > 0) || (rectangle.height > 0))
128 graphics.setXORMode(Color.gray);
129 graphics.setColor(Color.black);
130 graphics.drawRect(rectangle.x, rectangle.y,
131 rectangle.width, rectangle.height);
132 }
133 }
134
135 private void drawOval(Graphics graphics)
136 {
137 if (oval != null)
138 {
139 if ((oval.width > 0) || (oval.height > 0))
140 graphics.setXORMode(Color.gray);
141 graphics.setColor(Color.black);
142 graphics.drawOval(oval.x, oval.y,
143 oval.width, oval.height);
144 }
145 }
146
147 private void drawLine(Graphics graphics)
148 {
149 if (lineEndPoint != null)
150 {
151 graphics.setXORMode(Color.gray);
152 graphics.setColor(Color.black);
153 graphics.drawLine(lineStartPoint.x, lineStartPoint.y,
154 lineEndPoint.x, lineEndPoint.y);
155 }
156 }
157
158
159 private void setCursor()
160 {
161 switch (mode)
162 {
163 case MODE_LINE:
164 setCursor(Cursor.getPredefinedCursor(Cursor.CROSSHAIR_CURSOR));
165 break;
166
167 case MODE_TEXT:
168 setCursor(Cursor.getPredefinedCursor(Cursor.TEXT_CURSOR));
169 break;
170
171 case MODE_ERASER:
172 setCursor(Cursor.getPredefinedCursor(Cursor.MOVE_CURSOR));
173 break;
174
175 case MODE_FREEHAND:
176 setCursor(Cursor.getPredefinedCursor(Cursor.DEFAULT_CURSOR));
177 break;
178
179 case MODE_RECTANGLE:
180 setCursor(Cursor.getPredefinedCursor(Cursor.CROSSHAIR_CURSOR));
181 break;
182
183 case MODE_OVAL:
184 setCursor(Cursor.getPredefinedCursor(Cursor.CROSSHAIR_CURSOR));
185 break;
186 }
187 }
188
189 private boolean isTextCursorVisible()
190 {
191 return textCursorVisible;
192 }
193
194 private void setTextCursorVisible(Graphics g, boolean v)
195 {
196 if (v == true)
197 {
198 if (textCursorVisible == false)
199 {
200 FontMetrics fm = g.getFontMetrics();
201 g.setXORMode(Color.gray);
202
203 g.drawRect(textCursorPosition.x, textCursorPosition.y,
205 fm.charWidth('w'), fm.getHeight());
206 }
207 }
208 else {
210 if (textCursorVisible == true)
211 {
212 FontMetrics fm = g.getFontMetrics();
214 g.setXORMode(Color.gray);
215
216 g.drawRect(textCursorPosition.x, textCursorPosition.y,
218 fm.charWidth('w'), fm.getHeight());
219 }
220 }
221
222 textCursorVisible = v;
223 }
224
225 private void setTextCursorPosition(int x, int y)
226 {
227 textCursorPosition = new Point(x, y);
228 }
229
230 private void completeText()
231 {
232 if (textBuffer != null)
233 {
234 setTextCursorVisible(getGraphics(), false);
235 if (textBuffer.length() > 0)
236 {
237 TextObject object = new TextObject(WhiteBoardCanvas.this,
238 textStartPoint.x, textStartPoint.y,
239 textBuffer.toString());
240 object.draw();
241 addDrawnObject(object);
242
243 textBuffer = null;
244 setDefaultCursor();
245 }
246 }
247 }
248
249 public void addDrawingObject (WhiteBoardObjectInterface object)
251 {
252 objects.addElement(object);
253 object.draw();
254 }
255
256 private void addDrawnObject (WhiteBoardObjectInterface object)
258 {
259 objects.addElement(object);
260 if (listener != null)
261 {
262 listener.objectAdded(object);
263 }
264 }
265
266 public void registerObjectListener(ObjectListenerInterface listener)
267 {
268 this.listener = listener;
269 }
270
271 class MouseListener extends MouseAdapter
272 {
273 public void mousePressed(MouseEvent e)
274 {
275 switch(mode)
276 {
277 case MODE_FREEHAND:
278 setCursor();
279 freehandVector = new Vector();
280 break;
281
282 case MODE_TEXT:
283 completeText();
284
285 setCursor();
286 textBuffer = new StringBuffer ();
287 textStartPoint = new Point(e.getX(), e.getY());
288 Graphics g = getGraphics();
289 setTextCursorPosition(e.getX(),
290 e.getY() - g.getFontMetrics().getHeight());
291 setTextCursorVisible(g, true);
292 break;
293
294 case MODE_LINE:
295 setCursor();
296 lineStartPoint = new Point(e.getX(), e.getY());
297 break;
298
299 case MODE_ERASER:
300 setCursor();
301 eraserVector = new Vector();
302 break;
303
304 case MODE_RECTANGLE:
305 setCursor();
306 rectangleStartPoint = new Point(e.getX(), e.getY());
307 rectangle = new Rectangle(e.getX(), e.getY(), 0, 0);
308 break;
309
310 case MODE_OVAL:
311 setCursor();
312 ovalStartPoint = new Point(e.getX(), e.getY());
313 oval = new Rectangle(e.getX(), e.getY(), 0, 0);
314 break;
315 }
316
317 }
318
319 public void mouseReleased(MouseEvent e)
320 {
321 switch(mode)
322 {
323 case MODE_FREEHAND:
324 if (freehandVector.size() >= 2)
326 {
327 FreehandObject free_obj = new FreehandObject(WhiteBoardCanvas.this,
328 freehandVector);
329 addDrawnObject(free_obj);
330 }
331 setDefaultCursor();
332 break;
333
334 case MODE_LINE:
335 Graphics g = getGraphics();
337 drawLine(g);
338
339 lineEndPoint = new Point(e.getX(), e.getY());
340
341 drawLine(g);
343
344 LineObject line_object = new LineObject(WhiteBoardCanvas.this,
345 lineStartPoint,
346 lineEndPoint);
347 addDrawnObject(line_object);
348
349 lineStartPoint = null;
350 lineEndPoint = null;
351 setDefaultCursor();
352 break;
353
354 case MODE_ERASER:
355 if (eraserVector.size() >= 2)
357 {
358 EraserObject eraser_obj = new EraserObject(WhiteBoardCanvas.this,
359 eraserVector);
360 addDrawnObject(eraser_obj);
361 }
362 setDefaultCursor();
363 break;
364
365 case MODE_RECTANGLE:
366 g = getGraphics();
368 drawRectangle(g);
369
370 rectangle = RectangleObject.getRectangleDimension(rectangleStartPoint.x,
371 rectangleStartPoint.y,
372 e.getX(), e.getY());
373
374 drawRectangle(g);
376
377 RectangleObject rect_object = new RectangleObject(WhiteBoardCanvas.this,
378 rectangle);
379 addDrawnObject(rect_object);
380
381 rectangle = null;
382 setDefaultCursor();
383 break;
384
385
386 case MODE_OVAL:
387 g = getGraphics();
389 drawOval(g);
390
391 oval = OvalObject.getOvalDimension(ovalStartPoint.x,
392 ovalStartPoint.y,
393 e.getX(), e.getY());
394
395 drawOval(g);
397
398 OvalObject oval_object = new OvalObject(WhiteBoardCanvas.this,
399 oval);
400 addDrawnObject(oval_object);
401
402 oval = null;
403 setDefaultCursor();
404 break;
405 }
406 }
407 }
408
409 class MouseMotionListener extends MouseMotionAdapter
410 {
411 public void mouseDragged(MouseEvent e)
412 {
413 switch(mode)
414 {
415 case MODE_FREEHAND:
416 Point p = new Point(e.getX(), e.getY());
417 freehandVector.addElement(p);
418
419 int size = freehandVector.size();
421 if (size > 1)
422 {
423 Point start = (Point)freehandVector.elementAt(size - 2);
424 Point end = (Point)freehandVector.elementAt(size - 1);
425 Graphics g = getGraphics();
426 g.setColor(Color.black);
427
428 for (int j = 0; j < FreehandObject.DEFAULT_FREEHAND_TIP_SIZE; j++)
429 {
430 g.drawLine(start.x + j, start.y, end.x + j, end.y);
431 }
432 }
433 break;
434
435 case MODE_LINE:
436 Graphics g = getGraphics();
437
438 drawLine(g);
440
441 lineEndPoint = new Point(e.getX(), e.getY());
442
443 drawLine(g);
445 break;
446
447 case MODE_ERASER:
448 p = new Point(e.getX(), e.getY());
449 eraserVector.addElement(p);
450
451 size = eraserVector.size();
453 if (size > 1)
454 {
455 Point start = (Point)eraserVector.elementAt(size - 2);
456 Point end = (Point)eraserVector.elementAt(size - 1);
457 g = getGraphics();
458 g.setColor(getBackground());
459
460 for (int j = 0; j < EraserObject.DEFAULT_ERASER_TIP_SIZE; j++)
461 {
462 g.drawLine(start.x+j, start.y, end.x+j, end.y);
463 }
464 }
465 break;
466
467 case MODE_RECTANGLE:
468 g = getGraphics();
470 drawRectangle(g);
471
472 rectangle = RectangleObject.getRectangleDimension(rectangleStartPoint.x,
473 rectangleStartPoint.y, e.getX(), e.getY());
474
475 drawRectangle(g);
477 break;
478
479
480 case MODE_OVAL:
481 g = getGraphics();
483 drawOval(g);
484
485 oval = OvalObject.getOvalDimension(ovalStartPoint.x,
486 ovalStartPoint.y,
487 e.getX(), e.getY());
488
489 drawOval(g);
491 }
492 }
493 }
494
495 class KeyListener extends KeyAdapter
496 {
497 public void keyTyped(KeyEvent e)
498 {
499 if (mode == MODE_TEXT)
500 {
501 if (textBuffer != null)
502 {
503 char key = e.getKeyChar();
504
505 switch(key)
506 {
507 case '\b':
508 if (textBuffer != null)
509 {
510 if (textBuffer.length() > 0)
511 {
512 setTextCursorVisible(getGraphics(), false);
513
514 Graphics g = getGraphics();
515 FontMetrics fm = g.getFontMetrics();
516
517 String old_string = textBuffer.toString();
520 char last_char = old_string.charAt(old_string.length()
521 - 1);
522
523 String text = old_string.substring(0,
524 textBuffer.length() - 1);
525 textBuffer = new StringBuffer (text);
526
527 int x = textStartPoint.x + fm.stringWidth(text);
529 int y = textStartPoint.y;
530 g.setColor(getBackground());
531 g.fillRect(x, y - fm.getHeight(),
532 fm.charWidth(last_char),
533 fm.getHeight());
534
535 setTextCursorPosition(x, y - fm.getHeight());
536 setTextCursorVisible(getGraphics(), true);
537 }
538 }
539 break;
540
541 case '\r':
542 break;
543
544 case '\n':
545 completeText();
546 break;
547
548 default:
549 Graphics g = getGraphics();
550 FontMetrics fm = g.getFontMetrics();
551
552 setTextCursorVisible(g, false);
553
554 int x = textStartPoint.x + fm.stringWidth(textBuffer.toString());
555 int y = textStartPoint.y;
556 char[] c = null;
557
558 if (key == '\t')
559 {
560 c = new char[8];
561 for (int i = 0; i < c.length; i++)
562 {
563 c[i] = ' ';
564 }
565 }
566 else
567 {
568 c = new char[1];
569 c[0] = key;
570 }
571
572 Graphics tg = getGraphics();
573 tg.setColor(Color.black);
574 tg.drawString(new String (c), x, y);
575 textBuffer.append(key);
576
577 setTextCursorPosition(textStartPoint.x +
578 fm.stringWidth(textBuffer.toString()),
579 y - fm.getHeight());
580 setTextCursorVisible(g, true);
581 break;
582 }
583 }
584 }
585 }
586 }
587
588 }
589 |
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