Intercepting mouse click on the expand/collapse icon of a gantt table in a JSF JViews Gantt application

You can intercept the selection event via the interceptInteractor. This interceptInteractor can be configured with various interators including selectInteractor, tooltipInteractor, etc.

In order to determine if the mouse click occurs on the expand/collapse icon or somewhere else along the row of a gantt table, you must have access to the mouse event. Furthermore, you will need to rely on the tooltip data of the hitmap to determine if the mouse location is on the expand/collapse icon or at the activity's title. Consequently, you should use intercept interactor on tooltip interactor rather than on select interactor.

Below is sample code you can add in your JSP file to declare such tooltip and intercept interactors; as well as JavaScript code implementing detection of mouse click location thanks to hitmap technology. The beforeTableSelect function illustrates how to detect if a row is already selected and if mouse click occurred on the expand/collapse icon or somewhere else on the Gantt table row:

<script type="text/javascript">
    var selectedId="";
</script>
...
<jvf:tooltipInteractor id="tableTooltip" template="tooltip_callback"/>
<jv:interceptInteractor beforeHandler="beforeTableSelect" interactor="tableTooltip" eventType="mouseUp" id="tooltipIntercept"/>
...
function beforeTableSelect(e) {
 var selection = gantt.getTableView().getSelectionManager()
                   .getSelection();
 if (!selection) {
    alert("No selection");
 } else { // some selection
    if (selection.length == 1) {
      if (selectedId != selection[0].id) {
        selectedId = selection[0].id;
        // check if mouse click is on expand icon
        var view = gantt.getTableView();
        var tooltip = view.getHitInfos().tooltip;
        var hitmap = view.hitmap;
        var x = e.mouseX, y = e.mouseY;
        x += view.ganttView.tableScrollbar.value;
    if(hitmap ){
          var index = hitmap.hittest(x, y);
          if( index != 0 ) {
             if( !tooltip[index].indexGroup) //not at expand icon
                alert("New selection");
             }
         else {
       selectedId = "";
         }
          }
        }
        //else {
            //alert("Already selected");
        //}
      }//selection.length == 1
      else {  // deselect
         selectedId = "";
      }
  }// else some selection
}