GanttView.QueryKeepTasksLinked Event

Occurs each time the task hierarchy and order is changed and allows you to keep two tasks linked even if they organize a cyclic task connection or a child task links to its summary task. This is a routed event.

Namespace: DevExpress.Xpf.Gantt

Assembly: DevExpress.Xpf.Gantt.v25.1.dll

NuGet Package: DevExpress.Wpf.Gantt

Declaration

C#

public event EventHandler<QueryKeepTasksLinkedEventArgs> QueryKeepTasksLinked

VB.NET

Public Event QueryKeepTasksLinked As EventHandler(Of QueryKeepTasksLinkedEventArgs)

Event Data

The QueryKeepTasksLinked event's data class is DevExpress.Xpf.Gantt.QueryKeepTasksLinkedEventArgs.

Remarks

In versions prior to v19.2, changing Gantt tasks’ order or hierarchy might lead to the following:

• an existing link between tasks connects a summary task and one of its child tasks
• an existing link causes a cyclic connection between the tasks

If these links were not deleted, the scheduling and critical path calculation features did not work.

Starting with v19.2, these links are deleted automatically. You can keep them by handling the QueryKeepTasksLinked event:

C#

gantt.View.QueryKeepTasksLinked += (sender, e) => e.KeepLinked = true; 

VB.NET

AddHandler g.View.QueryKeepTasksLinked, Function(sender, e) e.KeepLinked = True 

Use the QueryAllowPredecessorLinkEdit event to create custom rules and limitations for task connectors.