How to create dynamic DataTable with dynamic header/column in JSF?

Question

Hello everyone,
I am having problem of programmatically create multiple DataTables which have different number of column? In my JSF page, I should implement a navigation table and a data table. The navigation table displays the links of all tables in the database so that the data table will load the data when the user click any link in navigation table. I have gone through [BalusC's post|http://balusc.blogspot.com/2006/06/using-datatables.html#PopulateDynamicDatatable] and I found that the section "populate dynamic datatable" does show me some hints. In his code,
// Iterate over columns.
        for (int i = 0; i < dynamicList.get(0).size(); i++) {
            // Create <h:column>.
            HtmlColumn column = new HtmlColumn();
            dynamicDataTable.getChildren().add(column);
            // Create <h:outputText value="dynamicHeaders"> for <f:facet name="header"> of column.
HtmlOutputText header = new HtmlOutputText();
header.setValue(dynamicHeaders[i]);
column.setHeader(header);
// Create <h:outputText value="#{dynamicItem[" + i + "]}"> for the body of column.
HtmlOutputText output = new HtmlOutputText();
output.setValueExpression("value",
createValueExpression("#{dynamicItem[" + i + "]}", String.class));
column.getChildren().add(output);
public HtmlPanelGroup getDynamicDataTableGroup() {
// This will be called once in the first RESTORE VIEW phase.
if (dynamicDataTableGroup == null) {
loadDynamicList(); // Preload dynamic list.
populateDynamicDataTable(); // Populate editable datatable.
return dynamicDataTableGroup;
I suppose the Getter method is only called once when the JSF page is loaded for the first time. By calling this Getter, columns are dynamically added to the table. However in my particular case, the dynamic list is not known until the user choose to view a table. That means I can not call loadDynamicList() in the Getter method. Subsequently, I can not execute the for loop in method "populateDynamicDataTable()".
So, how can I implement a real dynamic datatable with dynamic columns, or in other words, a dynamic table that can load data from different data tables (different number of columns) in the database at run-time?
Many thanks for any help in advance.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               

Answer 1

flyeminent wrote:
However in my particular case, the dynamic list is not known until the user choose to view a table. Then move the call from the getter to the bean's action method.