SharePoint

I'm using SharePoint online and have a SharePoint-hosted app.

I have a page with a question form that send data in to Sharepoint. I show my question form in my DispForm for my list (i added my app as an app part) on DispForm. When i select a item and press on view item i see my question form just as i like it but i don't know how to get the rigth ID of that item i want to show. Someone have any suggestion? i use

listItem.set_item('Title', $('#Title').val());
to send data in to my sahrepoint list and

and get_fieldValues to read it back

$('#Title').val(item.get_fieldValues().Title);

SPWorkflowManager.CancelWorkflow(workflowProperties.Workflow)

Throw New Exception("Ending Workflow")

var query;
        query += "<View>";
        query += "  <ViewFields>";
        query += "      <FieldRef Name='ItemStatus' />";
        query += "      <FieldRef Name='ItemDate' />";
        query += "      <FieldRef Name='myReviewedBy' />";
        query += "  </ViewFields>";
        query += "  <ProjectedFields>";
        query += "      <Field Name='myReviewedBy' Type='Lookup' List='myTransactionHeaders' ShowField='ReviewedBy' />";
        query += "  </ProjectedFields>";
        query += "  <Joins>";
        query += "      <Join Type='Left' ListAlias='myTransactionHeaders'>";
        query += "          <Eq>";
        query += "              <FieldRef Name='TransactionHeader' RefType='Id' />";
        query += "              <FieldRef List='myTransactionHeaders' Name='ID'>";
        query += "          </Eq>";
        query += "      </Join>";
        query += "  </Joins>";
        query += "</View>";

var ctx = new SP.ClientContext.get_current();
        var camlQuery = new SP.CamlQuery();
        camlQuery.set_viewXml(myCaml);
        var list = ctx.get_web().get_lists().getByTitle("TransactionItems");
        ctx.load(list);
        TransactionItem.TransactionItems = list.getItems(query);
        ctx.load(TransactionItem.TransactionItems);
        ctx.executeQueryAsync(readItemsSuccess, error);