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1
2
23
24 package javax.microedition.lcdui;
25
26 public class Form extends Screen
27 {
28 Item items[] = new Item[4];
29 int numOfItems = 0;
30 int focusItemIndex;
31 ItemStateListener itemStateListener = null;
32
33
34 public Form(String title)
35 {
36 super(title);
37 focusItemIndex = -2;
38 }
39
40
41 public Form(String title, Item[] items)
42 {
43 this(title);
44
45 this.items = items;
46 numOfItems = items.length;
47 for (int i = 0; i < numOfItems; i++) {
48 verifyItem(items[i]);
49 }
50 }
51
52
53 public int append(Item item)
54 {
55 verifyItem(item);
56
57 if (numOfItems + 1 == items.length) {
58 Item newitems[] = new Item[numOfItems + 4];
59 System.arraycopy(items, 0, newitems, 0, numOfItems);
60 items = newitems;
61 }
62 items[numOfItems] = item;
63 numOfItems++;
64
65 return (numOfItems - 1);
66 }
67
68
69 public int append(Image img)
70 {
71 return append(new ImageItem(null, img, ImageItem.LAYOUT_DEFAULT, null));
72 }
73
74
75 public int append(String str)
76 {
77 if (str == null) {
78 throw new NullPointerException();
79 }
80
81 return append(new StringItem(null, str));
82 }
83
84
85 public void delete(int itemNum)
86 {
87 verifyItemNum(itemNum);
88
89 items[itemNum].setOwner(null);
90 System.arraycopy(
91 items,
92 itemNum + 1,
93 items,
94 itemNum,
95 numOfItems - itemNum - 1);
96 numOfItems--;
97 }
98
99
100 public Item get(int itemNum)
101 {
102 verifyItemNum(itemNum);
103
104 return items[itemNum];
105 }
106
107
108 public void insert(int itemNum, Item item)
109 {
110 verifyItemNum(itemNum);
111 verifyItem(item);
112
113 if (numOfItems + 1 == items.length) {
114 Item newitems[] = new Item[numOfItems + 4];
115 System.arraycopy(items, 0, newitems, 0, numOfItems);
116 items = newitems;
117 }
118 System.arraycopy(
119 items,
120 itemNum,
121 items,
122 itemNum + 1,
123 numOfItems - itemNum);
124 items[itemNum] = item;
125 items[itemNum].setOwner(this);
126 numOfItems++;
127 }
128
129
130 public void set(int itemNum, Item item)
131 {
132 verifyItemNum(itemNum);
133 verifyItem(item);
134
135 items[itemNum] = item;
136 items[itemNum].setOwner(this);
137 }
138
139
140 public void setItemStateListener(ItemStateListener iListener)
141 {
142 itemStateListener = iListener;
143 }
144
145
146 public int size()
147 {
148 return numOfItems;
149 }
150
151
152 int paintContent(Graphics g)
153 {
154 int contentHeight = 0;
155 int translateY;
156 for (int i = 0; i < numOfItems; i++) {
157 translateY = items[i].paint(g);
158 g.translate(0, translateY);
159 contentHeight += translateY;
160 }
161 g.translate(0, -contentHeight);
162
163 return contentHeight;
164 }
165
166
167 int getHeight()
168 {
169 int height = 0;
170
171 for (int i = 0; i < numOfItems; i++) {
172 height += items[i].getHeight();
173 }
174
175 return height;
176 }
177
178
179 void hideNotify()
180 {
181 super.hideNotify();
182
183 for (int i = 0; i < numOfItems; i++) {
184 if (items[i].isFocusable() && items[i].hasFocus()) {
185 items[i].setFocus(false);
186 focusItemIndex = -2;
187 break;
188 }
189 }
190 }
191
192
193 void keyPressed(int keyCode)
194 {
195 if (focusItemIndex != -1) {
196 if (Display.getGameAction(keyCode) == Canvas.FIRE) {
197 items[focusItemIndex].select();
198 if (itemStateListener != null) {
199 itemStateListener.itemStateChanged(items[focusItemIndex]);
200 }
201 } else {
202 items[focusItemIndex].keyPressed(keyCode);
203 }
204 }
205
206 super.keyPressed(keyCode);
207 }
208
209
210 void showNotify()
211 {
212 super.showNotify();
213
214 if (focusItemIndex == -2) {
215 focusItemIndex = -1;
216
217 for (int i = 0; i < numOfItems; i++) {
218 if (items[i].isFocusable()) {
219 items[i].setFocus(true);
220 focusItemIndex = i;
221 break;
222 }
223 }
224 }
225 }
226
227
228 int traverse(int gameKeyCode, int top, int bottom)
229 {
230 int height, testItemIndex, traverse, i;
231 int topItemIndex, bottomItemIndex;
232
233 if (numOfItems == 0) {
234 return 0;
235 }
236
237 if (gameKeyCode == Canvas.UP) {
238 topItemIndex = getTopVisibleIndex(top);
239 if (focusItemIndex == -1) {
240 testItemIndex = topItemIndex;
241 height = getHeightToItem(testItemIndex);
242 traverse =
243 items[testItemIndex].traverse(
244 gameKeyCode,
245 top - height,
246 bottom - height,
247 false);
248 } else {
249 testItemIndex = focusItemIndex;
250 height = getHeightToItem(testItemIndex);
251 traverse =
252 items[testItemIndex].traverse(
253 gameKeyCode,
254 top - height,
255 bottom - height,
256 true);
257 }
258 if (traverse != Item.OUTOFITEM) {
259 if (focusItemIndex == -1
260 && items[testItemIndex].isFocusable()) {
261 items[testItemIndex].setFocus(true);
262 focusItemIndex = testItemIndex;
263 }
264 return traverse;
265 } else {
266 if (testItemIndex > 0) {
267 for (i = testItemIndex - 1; i >= topItemIndex; i--) {
272 if (items[i].isFocusable()) {
273 if (focusItemIndex != -1) {
274 items[focusItemIndex].setFocus(false);
275 }
276 items[i].setFocus(true);
277 focusItemIndex = i;
278 height = getHeightToItem(i);
279 traverse =
280 items[i].traverse(
281 gameKeyCode,
282 top - height,
283 bottom - height,
284 false);
285 if (traverse == Item.OUTOFITEM) {
286 return 0;
287 } else {
288 return traverse;
289 }
290 }
291 }
292 height = getHeightToItem(topItemIndex);
294 traverse =
295 items[topItemIndex].traverse(
296 gameKeyCode,
297 top - height,
298 bottom - height,
299 false);
300 if (traverse == Item.OUTOFITEM) {
301 } else {
302 bottomItemIndex = getTopVisibleIndex(bottom + traverse);
306 if (focusItemIndex != -1
307 && focusItemIndex > bottomItemIndex) {
308 items[focusItemIndex].setFocus(false);
309 focusItemIndex = -1;
310 }
311 return traverse;
312 }
313 }
314 }
315 }
316 if (gameKeyCode == Canvas.DOWN) {
317 bottomItemIndex = getBottomVisibleIndex(bottom);
318 if (focusItemIndex == -1) {
319 testItemIndex = bottomItemIndex;
320 height = getHeightToItem(testItemIndex);
321 traverse =
322 items[testItemIndex].traverse(
323 gameKeyCode,
324 top - height,
325 bottom - height,
326 false);
327 } else {
328 testItemIndex = focusItemIndex;
329 height = getHeightToItem(testItemIndex);
330 traverse =
331 items[testItemIndex].traverse(
332 gameKeyCode,
333 top - height,
334 bottom - height,
335 true);
336 }
337 if (traverse != Item.OUTOFITEM) {
338 if (focusItemIndex == -1
339 && items[testItemIndex].isFocusable()) {
340 items[testItemIndex].setFocus(true);
341 focusItemIndex = testItemIndex;
342 }
343 return traverse;
344 } else {
345 if (testItemIndex < numOfItems - 1) {
346 for (i = testItemIndex + 1; i <= bottomItemIndex; i++) {
351 if (items[i].isFocusable()) {
352 if (focusItemIndex != -1) {
353 items[focusItemIndex].setFocus(false);
354 }
355 items[i].setFocus(true);
356 focusItemIndex = i;
357 height = getHeightToItem(i);
358 traverse =
359 items[i].traverse(
360 gameKeyCode,
361 top - height,
362 bottom - height,
363 false);
364 if (traverse == Item.OUTOFITEM) {
365 return 0;
366 } else {
367 return traverse;
368 }
369 }
370 }
371 height = getHeightToItem(bottomItemIndex);
373 traverse =
374 items[bottomItemIndex].traverse(
375 gameKeyCode,
376 top - height,
377 bottom - height,
378 false);
379 if (traverse == Item.OUTOFITEM) {
380 } else {
381 topItemIndex = getTopVisibleIndex(top + traverse);
385 if (focusItemIndex != -1
386 && focusItemIndex < topItemIndex) {
387 items[focusItemIndex].setFocus(false);
388 focusItemIndex = -1;
389 }
390 return traverse;
391 }
392 }
393 }
394 }
395
396 return 0;
397 }
398
399
400 int getTopVisibleIndex(int top)
401 {
402 int height = 0;
403
404 for (int i = 0; i < numOfItems; i++) {
405 height += items[i].getHeight();
406 if (height >= top) {
407 return i;
408 }
409 }
410
411 return numOfItems - 1;
412 }
413
414
415 int getBottomVisibleIndex(int bottom)
416 {
417 int height = 0;
418
419 for (int i = 0; i < numOfItems; i++) {
420 height += items[i].getHeight();
421 if (height > bottom) {
422 return i;
423 }
424 }
425
426 return numOfItems - 1;
427 }
428
429
430 int getHeightToItem(int itemIndex)
431 {
432 int height = 0;
433
434 for (int i = 0; i < itemIndex; i++) {
435 height += items[i].getHeight();
436 }
437
438 return height;
439 }
440
441
449 private void verifyItem(Item item)
450 {
451 if (item == null) {
453 throw new NullPointerException("item is null");
454 }
455 if (item.getOwner() != null) {
456 throw new IllegalStateException("item is already owned");
457 }
458 item.setOwner(this);
460 }
461
462
469 private void verifyItemNum(int itemNum)
470 {
471 if (itemNum < 0 || itemNum >= numOfItems) {
472 throw new IndexOutOfBoundsException("item number is outside range of Form");
473 }
474 }
475
476 }
477 |
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