Multiple pagination scripts in one page

Question

function Pager(tableName, itemsPerPage) {
    this.tableName = tableName;
    this.itemsPerPage = itemsPerPage;
    this.currentPage = 1;
    this.pages = 0;
    this.inited = false;

    this.showRecords = function(from, to) {        
      var rows = document.getElementById(tableName).rows;
      // i starts from 1 to skip table header row
      for (var i = 1; i < rows.length; i++) {
         if (i < from || i > to)  
            rows[i].style.display = 'none';
         else
            rows[i].style.display = '';
    }
}

this.showPage = function(pageNumber) {
    if (! this.inited) {
        alert("not inited");
        return;
    }

    var oldPageAnchor = document.getElementById('pg'+this.currentPage);
    oldPageAnchor.className = 'pg-normal';

    this.currentPage = pageNumber;
    var newPageAnchor = document.getElementById('pg'+this.currentPage);
    newPageAnchor.className = 'pg-selected';

    var from = (pageNumber - 1) * itemsPerPage + 1;
    var to = from + itemsPerPage - 1;
    this.showRecords(from, to);
}   

this.prev = function() {
    if (this.currentPage > 1)
        this.showPage(this.currentPage - 1);
}

this.next = function() {
    if (this.currentPage < this.pages) {
        this.showPage(this.currentPage + 1);
    }
}                        

this.init = function() {
    var rows = document.getElementById(tableName).rows;
    var records = (rows.length - 1); 
    this.pages = Math.ceil(records / itemsPerPage);
    this.inited = true;
}

this.showPageNav = function(pagerName, positionId) {
    if (! this.inited) {
        alert("not inited");
            return;
        }
        var element = document.getElementById(positionId);

        var pagerHtml = '<a id="myshow" onmousemove="one()"  onclick="' + pagerName + '.prev();" class="pg-normal pgnleft"> &#171 Prev </a>  ';
        for (var page = 1; page <= this.pages; page++) 
            pagerHtml += '<span id="pg' + page + '" class="pg-normal" onclick="' + pagerName + '.showPage(' + page + ');">' + page + '</span>  ';
        pagerHtml += '<span onclick="'+pagerName+'.next();" class="pg-normal pgnright"> Next &#187;</span>';            

        element.innerHTML = pagerHtml;
    }
}

I'm using that as a pagination script on a page I'm trying to make.

<script type="text/javascript"><!--
    var pager = new Pager('results', 2); 
    pager.init(); 
    pager.showPageNav('pager', 'pageNavPosition'); 
    pager.showPage(2);
//--></script>

I have 5 tables in one page that is uses the first script so I tried putting the script above at the end of each table. When I do that, the paginations shows up and works but the pg-selected does not work. Is there anything I'm doing wrong? I also do this:

<script type="text/javascript"><!--
    var pager2 = new Pager('results2', 2); 
    pager2.init(); 
    pager2.showPageNav('pager2', 'pageNavPosition2'); 
    pager2.showPage(2);
//--></script>

at the end of each table, I just replace the table name(results2 to results3, results4...). It looks wrong. Is there anyone there that can explain what I'm doing wrong?

Answer 1

The problem is that your script generates elements with IDs. IDs are supposed to be unique. When the scripts calls document.getElementById('pg'+this.currentPage); , it will get the first element in the DOM with this ID, not the one that logaically belongs to the pagination instance. Use classes instead.