summaryrefslogtreecommitdiff
path: root/framework/Web/UI/WebControls/TListControl.php
blob: ff89a74d98b6d818ddfd803b614222a3db1c57fa (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
<?php

/**
 * TListControl class file
 *
 * @author Robin J. Rogge <rojaro@gmail.com>
 * @author Qiang Xue <qiang.xue@gmail.com>
 * @link https://github.com/pradosoft/prado
 * @copyright Copyright &copy; 2005-2015 The PRADO Group
 * @license https://github.com/pradosoft/prado/blob/master/COPYRIGHT
 * @package System.Web.UI.WebControls
 */

/**
 * Includes the supporting classes
 */
Prado::using('System.Web.UI.WebControls.TDataBoundControl');
Prado::using('System.Web.UI.WebControls.TListItem');
Prado::using('System.Collections.TListItemCollection');
Prado::using('System.Collections.TAttributeCollection');
Prado::using('System.Util.TDataFieldAccessor');

/**
 * TListControl class
 *
 * TListControl is a base class for list controls, such as {@link TListBox},
 * {@link TDropDownList}, {@link TCheckBoxList}, etc.
 * It manages the items and their status in a list control.
 * It also implements how the items can be populated from template and
 * data source.
 *
 * The property {@link getItems} returns a list of the items in the control.
 * To specify or determine which item is selected, use the
 * {@link getSelectedIndex SelectedIndex} property that indicates the zero-based
 * index of the selected item in the item list. You may also use
 * {@link getSelectedItem SelectedItem} and {@link getSelectedValue SelectedValue}
 * to get the selected item and its value. For multiple selection lists
 * (such as {@link TCheckBoxList} and {@link TListBox}), property
 * {@link getSelectedIndices SelectedIndices} is useful.
 *
 * TListControl implements {@link setAutoPostBack AutoPostBack} which allows
 * a list control to postback the page if the selections of the list items are changed.
 * The {@link setCausesValidation CausesValidation} and {@link setValidationGroup ValidationGroup}
 * properties may be used to specify that validation be performed when auto postback occurs.
 *
 * There are three ways to populate the items in a list control: from template,
 * using {@link setDataSource DataSource} and using {@link setDataSourceID DataSourceID}.
 * The latter two are covered in {@link TDataBoundControl}. To specify items via
 * template, using the following template syntax:
 * <code>
 * <com:TListControl>
 *   <com:TListItem Value="xxx" Text="yyy" >
 *   <com:TListItem Value="xxx" Text="yyy" Selected="true" >
 *   <com:TListItem Value="xxx" Text="yyy" >
 * </com:TListControl>
 * </code>
 *
 * When {@link setDataSource DataSource} or {@link setDataSourceID DataSourceID}
 * is used to populate list items, the {@link setDataTextField DataTextField} and
 * {@link setDataValueField DataValueField} properties are used to specify which
 * columns of the data will be used to populate the text and value of the items.
 * For example, if a data source is as follows,
 * <code>
 * $dataSource=array(
 *    array('name'=>'John', 'age'=>31),
 *    array('name'=>'Cary', 'age'=>28),
 *    array('name'=>'Rose', 'age'=>35),
 * );
 * </code>
 * setting {@link setDataTextField DataTextField} and {@link setDataValueField DataValueField}
 * to 'name' and 'age' will make the first item's text be 'John', value be 31,
 * the second item's text be 'Cary', value be 28, and so on.
 * The {@link setDataTextFormatString DataTextFormatString} property may be further
 * used to format how the item should be displayed. See {@link formatDataValue()}
 * for an explanation of the format string.
 *
 * The {@link setPromptText PromptText} and {@link setPromptValue PromptValue} properties can
 * be used to add a dummy list item that will be rendered first.
 *
 * @author Qiang Xue <qiang.xue@gmail.com>
 * @package System.Web.UI.WebControls
 * @since 3.0
 */
abstract class TListControl extends TDataBoundControl implements IDataRenderer
{
	/**
	 * @var TListItemCollection item list
	 */
	private $_items=null;
	/**
	 * @var boolean whether items are restored from viewstate
	 */
	private $_stateLoaded=false;
	/**
	 * @var mixed the following selection variables are used
	 * to keep selections when Items are not available
	 */
	private $_cachedSelectedIndex=-1;
	private $_cachedSelectedValue=null;
	private $_cachedSelectedIndices=null;
	private $_cachedSelectedValues=null;

	/**
	 * @return string tag name of the list control
	 */
	protected function getTagName()
	{
		return 'select';
	}

	/**
	 * @return boolean whether to render javascript.
	 */
	public function getEnableClientScript()
	{
		return $this->getViewState('EnableClientScript',true);
	}

	/**
	 * @param boolean whether to render javascript.
	 */
	public function setEnableClientScript($value)
	{
		$this->setViewState('EnableClientScript',TPropertyValue::ensureBoolean($value),true);
	}

	/**
	 * Adds attributes to renderer.
	 * @param THtmlWriter the renderer
	 */
	protected function addAttributesToRender($writer)
	{
		$page=$this->getPage();
		$page->ensureRenderInForm($this);
		if($this->getIsMultiSelect())
			$writer->addAttribute('multiple','multiple');
		if($this->getEnabled(true))
		{
			if($this->getAutoPostBack()
				&& $this->getEnableClientScript()
				&& $page->getClientSupportsJavaScript())
			{
				$this->renderClientControlScript($writer);
			}
		}
		else if($this->getEnabled())
			$writer->addAttribute('disabled','disabled');
		parent::addAttributesToRender($writer);
	}

	/**
	 * Renders the javascript for list control.
	 */
	protected function renderClientControlScript($writer)
	{
		$writer->addAttribute('id',$this->getClientID());
		$this->getPage()->getClientScript()->registerPostBackControl($this->getClientClassName(),$this->getPostBackOptions());
	}

	/**
	 * Gets the name of the javascript class responsible for performing postback for this control.
	 * Derived classes may override this method and return customized js class names.
	 * @return string the javascript class name
	 */
	protected function getClientClassName()
	{
		return 'Prado.WebUI.TListControl';
	}

	/**
	 * @return array postback options for JS postback code
	 */
	protected function getPostBackOptions()
	{
		$options['ID'] = $this->getClientID();
		$options['CausesValidation'] = $this->getCausesValidation();
		$options['ValidationGroup'] = $this->getValidationGroup();
		$options['EventTarget'] = $this->getUniqueID();
		return $options;
	}

	/**
	 * Adds object parsed from template to the control.
	 * This method adds only {@link TListItem} objects into the {@link getItems Items} collection.
	 * All other objects are ignored.
	 * @param mixed object parsed from template
	 */
	public function addParsedObject($object)
	{
		// Do not add items from template if items are loaded from viewstate
		if(!$this->_stateLoaded && ($object instanceof TListItem))
		{
			$index=$this->getItems()->add($object);
			if(($this->_cachedSelectedValue!==null && $this->_cachedSelectedValue===$object->getValue()) || ($this->_cachedSelectedIndex===$index))
			{
				$object->setSelected(true);
				$this->_cachedSelectedValue=null;
				$this->_cachedSelectedIndex=-1;
			}
		}
	}

	/**
	 * Performs databinding to populate list items from data source.
	 * This method is invoked by dataBind().
	 * You may override this function to provide your own way of data population.
	 * @param Traversable the data
	 */
	protected function performDataBinding($data)
	{
		$items=$this->getItems();
		if(!$this->getAppendDataBoundItems())
			$items->clear();
		$textField=$this->getDataTextField();
		if($textField==='')
			$textField=0;
		$valueField=$this->getDataValueField();
		if($valueField==='')
			$valueField=1;
		$textFormat=$this->getDataTextFormatString();
		$groupField=$this->getDataGroupField();
		foreach($data as $key=>$object)
		{
			$item=$items->createListItem();
			if(is_array($object) || is_object($object))
			{
				$text=TDataFieldAccessor::getDataFieldValue($object,$textField);
				$value=TDataFieldAccessor::getDataFieldValue($object,$valueField);
				$item->setValue($value);
				if($groupField!=='')
					$item->setAttribute('Group',TDataFieldAccessor::getDataFieldValue($object,$groupField));
			}
			else
			{
				$text=$object;
				$item->setValue("$key");
			}
			$item->setText($this->formatDataValue($textFormat,$text));
		}
		// SelectedValue or SelectedIndex may be set before databinding
		// so we make them be effective now
		if($this->_cachedSelectedValue!==null)
		{
			$this->setSelectedValue($this->_cachedSelectedValue);
			$this->resetCachedSelections();
		}
		else if($this->_cachedSelectedIndex!==-1)
		{
			$this->setSelectedIndex($this->_cachedSelectedIndex);
			$this->resetCachedSelections();
		}
		else if($this->_cachedSelectedValues!==null)
		{
			$this->setSelectedValues($this->_cachedSelectedValues);
			$this->resetCachedSelections();
		}
		else if($this->_cachedSelectedIndices!==null)
		{
			$this->setSelectedIndices($this->_cachedSelectedIndices);
			$this->resetCachedSelections();
		}
	}

	private function resetCachedSelections()
	{
		$this->_cachedSelectedValue=null;
		$this->_cachedSelectedIndex=-1;
		$this->_cachedSelectedValues=null;
		$this->_cachedSelectedIndices=null;
	}

	/**
	 * Creates a collection object to hold list items.
	 * This method may be overriden to create a customized collection.
	 * @return TListItemCollection the collection object
	 */
	protected function createListItemCollection()
	{
		return new TListItemCollection;
	}

	/**
	 * Saves items into viewstate.
	 * This method is invoked right before control state is to be saved.
	 */
	public function saveState()
	{
		parent::saveState();
		if($this->_items)
			$this->setViewState('Items',$this->_items->saveState(),null);
		else
			$this->clearViewState('Items');
	}

	/**
	 * Loads items from viewstate.
	 * This method is invoked right after control state is loaded.
	 */
	public function loadState()
	{
		parent::loadState();
		$this->_stateLoaded=true;
		if(!$this->getIsDataBound())
		{
			$this->_items=$this->createListItemCollection();
			$this->_items->loadState($this->getViewState('Items',null));
		}
		$this->clearViewState('Items');
	}

	/**
	 * @return boolean whether this is a multiselect control. Defaults to false.
	 */
	protected function getIsMultiSelect()
	{
		return false;
	}

	/**
	 * @return boolean whether performing databind should append items or clear the existing ones. Defaults to false.
	 */
	public function getAppendDataBoundItems()
	{
		return $this->getViewState('AppendDataBoundItems',false);
	}

	/**
	 * @param boolean whether performing databind should append items or clear the existing ones.
	 */
	public function setAppendDataBoundItems($value)
	{
		$this->setViewState('AppendDataBoundItems',TPropertyValue::ensureBoolean($value),false);
	}

	/**
	 * @return boolean a value indicating whether an automatic postback to the server
     * will occur whenever the user makes change to the list control and then tabs out of it.
     * Defaults to false.
	 */
	public function getAutoPostBack()
	{
		return $this->getViewState('AutoPostBack',false);
	}

	/**
	 * Sets the value indicating if postback automatically.
	 * An automatic postback to the server will occur whenever the user
	 * makes change to the list control and then tabs out of it.
	 * @param boolean the value indicating if postback automatically
	 */
	public function setAutoPostBack($value)
	{
		$this->setViewState('AutoPostBack',TPropertyValue::ensureBoolean($value),false);
	}

	/**
	 * @return boolean whether postback event trigger by this list control will cause input validation, default is true.
	 */
	public function getCausesValidation()
	{
		return $this->getViewState('CausesValidation',true);
	}

	/**
	 * @param boolean whether postback event trigger by this list control will cause input validation.
	 */
	public function setCausesValidation($value)
	{
		$this->setViewState('CausesValidation',TPropertyValue::ensureBoolean($value),true);
	}

	/**
	 * @return string the field of the data source that provides the text content of the list items.
	 */
	public function getDataTextField()
	{
		return $this->getViewState('DataTextField','');
	}

	/**
	 * @param string the field of the data source that provides the text content of the list items.
	 */
	public function setDataTextField($value)
	{
		$this->setViewState('DataTextField',$value,'');
	}

	/**
	 * @return string the formatting string used to control how data bound to the list control is displayed.
	 */
	public function getDataTextFormatString()
	{
		return $this->getViewState('DataTextFormatString','');
	}

	/**
	 * Sets data text format string.
	 * The format string is used in {@link TDataValueFormatter::format()} to format the Text property value
	 * of each item in the list control.
	 * @param string the formatting string used to control how data bound to the list control is displayed.
	 * @see TDataValueFormatter::format()
	 */
	public function setDataTextFormatString($value)
	{
		$this->setViewState('DataTextFormatString',$value,'');
	}

	/**
	 * @return string the field of the data source that provides the value of each list item.
	 */
	public function getDataValueField()
	{
		return $this->getViewState('DataValueField','');
	}

	/**
	 * @param string the field of the data source that provides the value of each list item.
	 */
	public function setDataValueField($value)
	{
		$this->setViewState('DataValueField',$value,'');
	}

	/**
	 * @return string the field of the data source that provides the label of the list item groups
	 */
	public function getDataGroupField()
	{
		return $this->getViewState('DataGroupField','');
	}

	/**
	 * @param string the field of the data source that provides the label of the list item groups
	 */
	public function setDataGroupField($value)
	{
		$this->setViewState('DataGroupField',$value,'');
	}

	/**
	 * @return integer the number of items in the list control
	 */
	public function getItemCount()
	{
		return $this->_items?$this->_items->getCount():0;
	}

	/**
	 * @return boolean whether the list control contains any items.
	 */
	public function getHasItems()
	{
		return ($this->_items && $this->_items->getCount()>0);
	}

	/**
	 * @return TListItemCollection the item collection
	 */
	public function getItems()
	{
		if(!$this->_items)
			$this->_items=$this->createListItemCollection();
		return $this->_items;
	}

	/**
	 * @return integer the index (zero-based) of the item being selected, -1 if no item is selected.
	 */
	public function getSelectedIndex()
	{
		if($this->_items)
		{
			$n=$this->_items->getCount();
			for($i=0;$i<$n;++$i)
				if($this->_items->itemAt($i)->getSelected())
					return $i;
		}
		return -1;
	}

	/**
	 * @param integer the index (zero-based) of the item to be selected
	 */
	public function setSelectedIndex($index)
	{
		if(($index=TPropertyValue::ensureInteger($index))<0)
			$index=-1;
		if($this->_items)
		{
			$this->clearSelection();
			if($index>=0 && $index<$this->_items->getCount())
				$this->_items->itemAt($index)->setSelected(true);
		}
		$this->_cachedSelectedIndex=$index;
		if($this->getAdapter() instanceof IListControlAdapter)
			$this->getAdapter()->setSelectedIndex($index);
	}

	/**
	 * @return array list of index of items that are selected
	 */
	public function getSelectedIndices()
	{
		$selections=array();
		if($this->_items)
		{
			$n=$this->_items->getCount();
			for($i=0;$i<$n;++$i)
				if($this->_items->itemAt($i)->getSelected())
					$selections[]=$i;
		}
		return $selections;
	}

	/**
	 * @param array list of index of items to be selected
	 */
	public function setSelectedIndices($indices)
	{
		if($this->getIsMultiSelect())
		{
			if($this->_items)
			{
				$this->clearSelection();
				$n=$this->_items->getCount();
				foreach($indices as $index)
				{
					if($index>=0 && $index<$n)
						$this->_items->itemAt($index)->setSelected(true);
				}
			}
			$this->_cachedSelectedIndices=$indices;
		}
		else
			throw new TNotSupportedException('listcontrol_multiselect_unsupported',get_class($this));

		if($this->getAdapter() instanceof IListControlAdapter)
			$this->getAdapter()->setSelectedIndices($indices);
	}

	/**
	 * @return TListItem|null the selected item with the lowest cardinal index, null if no item is selected.
	 */
	public function getSelectedItem()
	{
		if(($index=$this->getSelectedIndex())>=0)
			return $this->_items->itemAt($index);
		else
			return null;
	}

	/**
	 * Returns the value of the selected item with the lowest cardinal index.
	 * This method is required by {@link IDataRenderer}.
	 * It is the same as {@link getSelectedValue()}.
	 * @return string the value of the selected item with the lowest cardinal index, empty if no selection.
	 * @see getSelectedValue
	 * @since 3.1.0
	 */
	public function getData()
	{
		return $this->getSelectedValue();
	}

	/**
	 * Selects an item by the specified value.
	 * This method is required by {@link IDataRenderer}.
	 * It is the same as {@link setSelectedValue()}.
	 * @param string the value of the item to be selected.
	 * @see setSelectedValue
	 * @since 3.1.0
	 */
	public function setData($value)
	{
		$this->setSelectedValue($value);
	}

	/**
	 * @return string the value of the selected item with the lowest cardinal index, empty if no selection
	 */
	public function getSelectedValue()
	{
		$index=$this->getSelectedIndex();
		return $index>=0?$this->getItems()->itemAt($index)->getValue():'';
	}

	/**
	 * Sets selection by item value.
	 * Existing selections will be cleared if the item value is found in the item collection.
	 * Note, if the value is null, existing selections will also be cleared.
	 * @param string the value of the item to be selected.
	 */
	public function setSelectedValue($value)
    {
	    if($this->_items)
	    {
		    if($value===null)
		    	$this->clearSelection();
		    else if(($item=$this->_items->findItemByValue($value))!==null)
	    	{
		    	$this->clearSelection();
		    	$item->setSelected(true);
	    	}
	    	else
				$this->clearSelection();
    	}
    	$this->_cachedSelectedValue=$value;
		if($this->getAdapter() instanceof IListControlAdapter)
			$this->getAdapter()->setSelectedValue($value);
    }


	/**
	 * @return array list of the selected item values (strings)
	 */
	public function getSelectedValues()
	{
		$values=array();
		if($this->_items)
		{
			foreach($this->_items as $item)
			{
				if($item->getSelected())
					$values[]=$item->getValue();
			}
		}
		return $values;
	}

	/**
	 * @param array list of the selected item values
	 */
	public function setSelectedValues($values)
	{
		if($this->getIsMultiSelect())
		{
			if($this->_items)
			{
				$this->clearSelection();
				$lookup=array();
				foreach($this->_items as $item)
					$lookup[$item->getValue()]=$item;
				foreach($values as $value)
				{
					if(isset($lookup["$value"]))
						$lookup["$value"]->setSelected(true);
				}
			}
			$this->_cachedSelectedValues=$values;
		}
		else
			throw new TNotSupportedException('listcontrol_multiselect_unsupported',get_class($this));

		if($this->getAdapter() instanceof IListControlAdapter)
			$this->getAdapter()->setSelectedValues($values);
	}

    /**
     * @return string selected value
     */
    public function getText()
    {
	    return $this->getSelectedValue();
    }

    /**
     * @param string value to be selected
     */
    public function setText($value)
    {
	    $this->setSelectedValue($value);
    }

    /**
     * Clears all existing selections.
     */
    public function clearSelection()
    {
	    if($this->_items)
	    {
		    foreach($this->_items as $item)
		    	$item->setSelected(false);
	    }

		if($this->getAdapter() instanceof IListControlAdapter)
			$this->getAdapter()->clearSelection();
    }

	/**
	 * @return string the group of validators which the list control causes validation upon postback
	 */
	public function getValidationGroup()
	{
		return $this->getViewState('ValidationGroup','');
	}

	/**
	 * @param string the group of validators which the list control causes validation upon postback
	 */
	public function setValidationGroup($value)
	{
		$this->setViewState('ValidationGroup',$value,'');
	}

	/**
	 * @return string the prompt text which is to be displayed as the first list item.
	 * @since 3.1.1
	 */
	public function getPromptText()
	{
		return $this->getViewState('PromptText','');
	}

	/**
	 * @param string the prompt text which is to be displayed as the first list item.
	 * @since 3.1.1
	 */
	public function setPromptText($value)
	{
		$this->setViewState('PromptText',$value,'');
	}

	/**
	 * @return string the prompt selection value.
	 * @see getPromptText
	 * @since 3.1.1
	 */
	public function getPromptValue()
	{
		return $this->getViewState('PromptValue','');
	}

	/**
	 * @param string the prompt selection value. If empty, {@link getPromptText PromptText} will be used as the value.
	 * @see setPromptText
	 * @since 3.1.1
	 */
	public function setPromptValue($value)
	{
		$this->setViewState('PromptValue',(string)$value,'');
	}

	/**
	 * Raises OnSelectedIndexChanged event when selection is changed.
	 * This method is invoked when the list control has its selection changed
	 * by end-users.
	 * @param TEventParameter event parameter
	 */
	public function onSelectedIndexChanged($param)
	{
		$this->raiseEvent('OnSelectedIndexChanged',$this,$param);
		$this->onTextChanged($param);
	}

	/**
	 * Raises OnTextChanged event when selection is changed.
	 * This method is invoked when the list control has its selection changed
	 * by end-users.
	 * @param TEventParameter event parameter
	 */
	public function onTextChanged($param)
	{
		$this->raiseEvent('OnTextChanged',$this,$param);
	}

	/**
	 * Renders the prompt text, if any.
	 * @param THtmlWriter writer
	 * @since 3.1.1
	 */
	protected function renderPrompt($writer)
	{
		$text=$this->getPromptText();
		$value=$this->getPromptValue();
		if($value==='')
			$value=$text;
		if($value!=='')
		{
			$writer->addAttribute('value',$value);
			$writer->renderBeginTag('option');
			$writer->write(THttpUtility::htmlEncode($text));
			$writer->renderEndTag();
			$writer->writeLine();
		}
	}

	/**
	 * Renders body content of the list control.
	 * This method renders items contained in the list control as the body content.
	 * @param THtmlWriter writer
	 */
	public function renderContents($writer)
	{
		$this->renderPrompt($writer);

		if($this->_items)
		{
			$writer->writeLine();
			$previousGroup=null;
			foreach($this->_items as $item)
			{
				if($item->getEnabled())
				{
					if($item->getHasAttributes())
					{
						$group=$item->getAttributes()->remove('Group');
						if($group!==$previousGroup)
						{
							if($previousGroup!==null)
							{
								$writer->renderEndTag();
								$writer->writeLine();
								$previousGroup=null;
							}
							if($group!==null)
							{
								$writer->addAttribute('label',$group);
								$writer->renderBeginTag('optgroup');
								$writer->writeLine();
								$previousGroup=$group;
							}
						}
						foreach($item->getAttributes() as $name=>$value)
							$writer->addAttribute($name,$value);
					}
					else if($previousGroup!==null)
					{
						$writer->renderEndTag();
						$writer->writeLine();
						$previousGroup=null;
					}
					if($item->getSelected())
						$writer->addAttribute('selected','selected');
					$writer->addAttribute('value',$item->getValue());
					$writer->renderBeginTag('option');
					$writer->write(THttpUtility::htmlEncode($item->getText()));
					$writer->renderEndTag();
					$writer->writeLine();
				}
			}
			if($previousGroup!==null)
			{
				$writer->renderEndTag();
				$writer->writeLine();
			}
		}
	}

	/**
	 * Formats the text value according to a format string.
	 * If the format string is empty, the original value is converted into
	 * a string and returned.
	 * If the format string starts with '#', the string is treated as a PHP expression
	 * within which the token '{0}' is translated with the data value to be formated.
	 * Otherwise, the format string and the data value are passed
	 * as the first and second parameters in {@link sprintf}.
	 * @param string format string
	 * @param mixed the data to be formatted
	 * @return string the formatted result
	 */
	protected function formatDataValue($formatString,$value)
	{
		if($formatString==='')
			return TPropertyValue::ensureString($value);
		else if($formatString[0]==='#')
		{
			$expression=strtr(substr($formatString,1),array('{0}'=>'$value'));
			try
			{
				if(eval("\$result=$expression;")===false)
					throw new Exception('');
				return $result;
			}
			catch(Exception $e)
			{
				throw new TInvalidDataValueException('listcontrol_expression_invalid',get_class($this),$expression,$e->getMessage());
			}
		}
		else
			return sprintf($formatString,$value);
	}
}

/**
 * IListControlAdapter interface
 *
 * @author Wei Zhuo <weizhuo[at]gmail[dot]com>
 * @version $Revision: $  Sun Jun 25 04:53:43 EST 2006 $
 * @package System.Web.UI.ActiveControls
 * @since 3.0
 */
interface IListControlAdapter
{
	/**
	 * Selects an item based on zero-base index on the client side.
	 * @param integer the index (zero-based) of the item to be selected
	 */
	public function setSelectedIndex($index);
	/**
	 * Selects a list of item based on zero-base indices on the client side.
	 * @param array list of index of items to be selected
	 */
	public function setSelectedIndices($indices);

	/**
	 * Sets selection by item value on the client side.
	 * @param string the value of the item to be selected.
	 */
	public function setSelectedValue($value);

	/**
	 * Sets selection by a list of item values on the client side.
	 * @param array list of the selected item values
	 */
	public function setSelectedValues($values);

    /**
     * Clears all existing selections on the client side.
     */
    public function clearSelection();
}