Where is <t:dataScroller> tutorial?

From:

"<f:chukcha>" <chukcha14@gmail.com>

Newsgroups:

comp.lang.java.help

Date:

13 Dec 2006 18:48:06 -0800

Message-ID:

<1166064486.609491.107540@j72g2000cwa.googlegroups.com>

Hi all,
Does anybody have a link to a decent step by step, easy to understand
Tamahawk dataTable with dataScroller tutorial?
I searched the web and i find many articles describing some issues and
workarounds to some problems but I cannot find a SIMPLE but relatively
in depth tutorial on how the dataScroller component should be used and
why for example a dataTable can have 2 or more dataScrollers?!
I'm a JSF newbie and I'm going crazy here :) I already read the
wiki.apache.org/myfaces/ pages and i found them very informative, but
I need a "from the beginning" type, step by step, EASY to understand
tutorial on how to use dataScroller that can scroll through 2000 or so
records (without storing all those records in memory at once).

I built a small application that is supposed to read 5 records from db
and display them in a t:dataTable
For some reason it returns 10 records instead of five and It calls the
DB three times to do that!!!
(the SQL query is fine btw...)

Do I have "Gremlins" living in my program or what? :)))
I'm just trying to understand why...

Here is my code:

<t:dataTable id="playersTable" var="player"
value="#{playerListBkBean.dataModel}"
                                                 border="1"
                                                 rows="10">
        <t:column>
            <f:facet name="header">
                <h:outputText id="id" value="ID" />
            </f:facet>
            <h:outputLabel for="id" value="#{player.id}" />
        </t:column>

        <t:column>
            <f:facet name="header">
                <h:outputText id="id" value="User Name" />
            </f:facet>
            <h:outputLabel for="id" value="#{player.username}" />
        </t:column>

        <t:column>
            <f:facet name="header">
                <h:outputText id="name" value="Name" />
            </f:facet>
            <h:outputLabel for="name" value="#{player.name}" />
            <h:outputLabel for="name" value=" " />
            <h:outputLabel for="name" value="#{player.lastName}" />
        </t:column>

        <t:column>
            <f:facet name="header">
                <h:outputText id="casid" value="Casino ID" />
            </f:facet>
            <h:outputLabel for="casid" value="#{player.casinoId}" />
        </t:column>

        <t:column>
            <f:facet name="header">
                <h:outputText id="betLim" value="Bet Limits" />
            </f:facet>
            <t:commandLink value="view" action="#{playerListBkBean.view}">
                
            </t:commandLink>
        </t:column>

        <t:column>
            <f:facet name="header">
                <h:outputText id="lnk" value="Remove from list?" />
            </f:facet>
            <t:commandLink value="remove" action="#{playerListBkBean.remove}" />
        </t:column>

        </t:dataTable>
        <div class="edit_button">
            <t:commandButton action="#{playerListBkBean.edit}"
value="#{msg.playersearch_editBtn}" />
        </div>
    </div>
    <br />
    <br />
    <t:dataScroller id="pager" for="playersTable" pageCountVar="pageCount"
                 pageIndexVar="pageIndex"
               rowsCountVar="rowsCount"

                                                  firstRowIndexVar="firstRowIndex"
                                                  displayedRowsCountVar="displayedRowsCount"
                 fastStep="9"
                                                  paginator="true"

paginatorMaxPages="10"
paginatorTableClass="paginator"

paginatorActiveColumnStyle="font-weight:bold;">
    <f:facet name="first" >
        <h:graphicImage url="../images/fastreverse_arrow.jpg"/>
    </f:facet>

    <f:facet name="last">
     <h:graphicImage url="../images/ff_arrow.jpg"/>
    </f:facet>

    <f:facet name="previous">
     <h:graphicImage url="../images/rev_arrow.jpg"/>
    </f:facet>

    <f:facet name="next">
     <h:graphicImage url="../images/f_arrow.jpg"/>
    </f:facet>

    </t:dataScroller>

-----------------------------------------------------------------
Here is a snapshot of my paging hookup:
//---------------------------Data paging--------------------------

    private DataPage<Player> getDataPage(int startRow, int pageSize) {
          // access database here, or call EJB to do so
        List<Player> players = null;

        try {
            //TODO: add search type as well
            players = playerService.showPlayers(searchBean.getPlayerIds());
            System.out.println("Players number: "+players.size());
        }
        catch(NullPointerException n) {
            LOG.error("Null pointer exception. Probable cause: SearchBean in not
in session.");
            n.printStackTrace();
        }

        return new DataPage<Player>(pageSize, startRow, players);
    }

    public PlayerSearchDataModel getDataModel() {

        if (playersDataModel == null) {
            playersDataModel = new
PlayerSearchDataModel(PlayerListBkBean.rowsPerPage);
        }

        return playersDataModel;
    }

    //inner class below!!!
    private class PlayerSearchDataModel extends PagedListDataModel {
        public PlayerSearchDataModel(int pageSize) {
            super(pageSize);
        }

        public DataPage<Player> fetchPage(int startRow, int pageSize) {
            // call enclosing managed bean method to fetch the data
            return getDataPage(startRow, pageSize);
        }
    }
    //---------------------------End of data paging-------------------

Thank you in advance.

David