WOCheckboxMatrix.java

/*
 * WOCheckboxMatrix.java
 * (c) Copyright 2001 Apple Computer, Inc. All rights reserved.
 * This a modified version.
 * Original license: http://www.opensource.apple.com/apsl/
 */

package com.webobjects.woextensions;

import java.util.List;
import com.webobjects.appserver.WOComponent;
import com.webobjects.appserver.WOContext;
import com.webobjects.foundation.NSArray;
import com.webobjects.foundation.NSMutableArray;

/**
 * <span class="ja">
 * 記述サンプル： WORepetition がフォーム・バリューを計算するようにします。
 * 
 * This uses a technique of having the WORepetition compute the form values for us.
 * This is a bit strange to have the Repetition having form values.
 * It may well be clearer to simply use takeValuesFromRequest... in here and not use this trick.
 * The ability to ask an element for its elementID seems logical and useful
 * (as we use it for the umbrealla name here). Of course, we could have this on the component just as easily,
 *  and this may be clearer.
 *  However, if there is a repetition with a repetition in it, then the component's elementID isn't enough.
 *  </span>
 * 
 * <span class="en">
 * This uses a technique of having the WORepetition compute the form values for us.
 * This is a bit strange to have the Repetition having form values.
 * It may well be clearer to simply use takeValuesFromRequest... in here and not use this trick.
 * The ability to ask an element for its elementID seems logical and useful
 * (as we use it for the umbrealla name here). Of course, we could have this on the component just as easily,
 *  and this may be clearer.
 *  However, if there is a repetition with a repetition in it, then the component's elementID isn't enough.
 *  </span>
 */
public class WOCheckboxMatrix extends WOComponent {
	/**
	 * Do I need to update serialVersionUID?
	 * See section 5.6 <cite>Type Changes Affecting Serialization</cite> on page 51 of the
	 * <a href="http://java.sun.com/j2se/1.4/pdf/serial-spec.pdf">Java Object Serialization Spec</a>
	 */
	private static final long serialVersionUID = 1L;

    public Object currentItem;
    public int index;
    public String wrapperElementID;
    protected List _selections = null;

    public WOCheckboxMatrix(WOContext aContext) {
        super(aContext);
    }
    
    @Override
    public boolean isStateless() {
        return true;
    }
    
    /**
     * <span class="ja">カレント・アイテムをセットし、データを item としてプッシュします。 </span>
     */
    public void setCurrentItem(Object anItem) {
        currentItem = anItem;
        setValueForBinding(currentItem, "item");
    }

    /**
     * <span class="ja">データの選択範囲を取得 </span>
     */
    public List selections() {
        if (_selections == null) {
            _selections = (List)_WOJExtensionsUtil.valueForBindingOrNull("selections",this);
            if (_selections == null) {
                _selections = NSArray.EmptyArray;
            }
        }
        return _selections;
    }

    /**
     * <span class="ja">データの選択範囲をセット </span>
     */
    public void setSelections(List<String> aFormValuesArray) {
        // ** This is where we accept the formValues.  Kind of weird.
        NSMutableArray aSelectionsArray = new NSMutableArray();
        if (aFormValuesArray != null) {
            List anItemList = (List)_WOJExtensionsUtil.valueForBindingOrNull("list",this);
            if (anItemList == null) {
                anItemList = NSArray.EmptyArray;
            }
            int anItemCount = anItemList.size();
            for( String anIndexStr : aFormValuesArray ) {
            	int i = Integer.parseInt( anIndexStr );
                if (i < anItemCount) {
                    Object anObject = anItemList.get(i);
                    aSelectionsArray.addObject(anObject);
                } else {
                    // ** serious problem here. Raise an exception?
                }
            }
        }
        setValueForBinding(aSelectionsArray, "selections");
        _selections = null;
    }

    /**
     * <span class="ja">カレント・アイテムがチェックされている？ </span>
     */
    public String isCurrentItemChecked() {
        if ((selections() != null) && selections().contains(currentItem)) {
            return "checked";
        }
        return null;
    }


    protected void _invalidateCaches() {
        _selections=null;
        currentItem = null;
    }

    @Override
    public void reset()  {
        _invalidateCaches();
    }

    public Object nullValue() {
    	return null;
    }
}