Sort columns of a table

[Former Member]

Hi,

Is it possible to sort columns in a IWDTable object?

The column headers of a table requires a IWDCaption object, which cannot be linked to an action.

Has anyone tried to sort tables by column header before?? Is it possible??

Thanks,

[BeGanz]

The <b>IWDNode</b> interface provides a method sortElements:

public void  sortElements(java.util.Comparator comparator)

<i> Sorts the elements according to the Comparator. The Comparator gets IWDNodeElements for this node. Since Collections.sort(List) is used, this sort is guaranteed to be stable: equal elements will not be reordered as a result of the sort.</i>

The comparator has to be implemented by your own, e.g. as a separate class in folder src/packages/<package> ... /MyComparator.java or as an inner class in your Web Dynpro controller. Assume you have declared a context value node MyData in the context of controller MyView. For sorting the contained node elements based on value attribute MyAttribute you would call

wdContext.nodeMyData().sortElements(new MyDataComparator(sessionLocale);

The session locale can be retrieved via

WDResourceHandler.getCurrentSessionLocale()

The MyDataComparator class would look like this:

package com.mycompany.myapp.mycomp.util;
import java.util.*;
import java.text.*;
import com.mycompany.myapp.mycomp.wdp.IPrivateMyView;
/**
* MyComparator is used by the generic sorting-mechanism provided by IWDNode. 
*/
public class MyComparator implements Comparator {
private Collator collator; 
/**
* Constructor for MyComparator. Need local-information for correct sorting.
*/
public MyComparator(Locale locale) {
super();
this.collator = Collator.getInstance(locale);
}
/**
* @see java.util.Comparator#compare(Object, Object)
*/
public int compare(Object o1, Object o2) {
IPrivateMyView.IMyDataElement e1 = (IPrivateMyView.IMyDataElement ) o1;
IPrivateMyView.IMyDataElement e2 = (IPrivateMyView.IMyDataElement ) o2;
return collator.compare(e1.getMyAttribute(), e2.getMyAttribute()); 
}
}

Be aware of the fact that a Collator is used for local-specific sorting and that you have to cast the objects o1 and o2 to the generated type of your own node element (here IPrivateMyView.IMyDataElement for a View Controller named <i>MyView</i>).

Greetings, Bertram

[Former Member]

IWDTableColumn has a method setOnAction(IWDAction) that associates an action with a table column. This action is triggered when the column header is clicked.

You might also have a look at the sort()-method for context nodes.

Regards, Armin