GanttControl.CustomDrawTask Event

Fires before a task in the chart area is displayed. Provides access to a drawing surface and allows you to draw the task manually.

Namespace: DevExpress.XtraGantt

Assembly: DevExpress.XtraGantt.v20.2.dll

NuGet Package: DevExpress.Win.Gantt

Declaration

C#

[DXCategory("Events")]
public event CustomDrawTaskEventHandler CustomDrawTask

VB.NET

<DXCategory("Events")>
Public Event CustomDrawTask As CustomDrawTaskEventHandler

Event Data

The CustomDrawTask event's data class is CustomDrawTaskEventArgs. The following properties provide information specific to this event:

Property	Description
Appearance	Provides access to the task’s appearance settings.
Duration	Gets the task duration.
FinishDate	Gets the task finish date.
Info	Provides access to view information about the task.
Node	Gets the processed node.
Progress	Gets the task progress.
StartDate	Gets the task start date.
State	Gets the object state: normal, hot tracked, pressed, disabled, or selected.

The event data class exposes the following methods:

Method	Description
DrawBaseline()	Draws the baseline.
DrawBaseline(RectangleF)	Draws the baseline in the specified bounds.
DrawInsideText()	Draws the text inside the bar.
DrawLeftLinkPoint()	Draws a dependency connection point at the left side of the task.
DrawLeftText()	Draws the text to the left of the bar.
DrawLeftText(RectangleF)	Draws the text to the left of the bar within the specified bounds.
DrawRightLinkPoint()	Draws a dependency connection point at the right side of the task.
DrawRightText()	Draws the text to the right of the bar.
DrawRightText(RectangleF)	Draws the text to the left of the bar within the specified bounds.
DrawShape()	Draws the task shape: bar, summary bar, or milestone.
DrawShape(DateTime, DateTime)	Draws the task shape (bar, summary bar, or milestone) with an interruption.
DrawShape(RectangleF, Single)	Draws the task shape: bar, summary bar, or milestone.
DrawSplit(RectangleF)
GetPosition(DateTime)	Returns the horizontal position of the specified date on the timescale.

Example

The code below shows how to highlight specific tasks and dependencies.

Run Demo: Highlight Tasks and Dependencies

C#

HashSet<int> tasks = new HashSet<int> { 1, 2, 3, 6, 7, 8, 10, 11, 13 };
ganttControl.CustomDrawTask += (sender, e) => {
    int taskId = Convert.ToInt32(e.Node.GetValue("Id"));
    if(tasks.Contains(taskId)) {
        e.Appearance.BackColor = DXSkinColors.FillColors.Warning;
        e.Appearance.ProgressColor = DXSkinColors.FillColors.Warning;
    }
};
ganttControl.CustomDrawTaskDependency += (sender, e) => {
    int predecessorId = Convert.ToInt32(e.PredecessorNode.GetValue("Id"));
    int successorId = Convert.ToInt32(e.SuccessorNode.GetValue("Id"));
    if(tasks.Contains(predecessorId) && tasks.Contains(successorId)) {
        e.Appearance.BackColor = DXSkinColors.FillColors.Warning;
    }
};

VB.NET

Dim tasks As New HashSet(Of Integer)() From {1, 2, 3, 6, 7, 8, 10, 11, 13}
AddHandler ganttControl.CustomDrawTask, Sub(sender, e)
    Dim taskId As Integer = Convert.ToInt32(e.Node.GetValue("Id"))
    If tasks.Contains(taskId) Then
        e.Appearance.BackColor = DXSkinColors.FillColors.Warning
        e.Appearance.ProgressColor = DXSkinColors.FillColors.Warning
    End If
End Sub
AddHandler ganttControl.CustomDrawTaskDependency, Sub(sender, e)
    Dim predecessorId As Integer = Convert.ToInt32(e.PredecessorNode.GetValue("Id"))
    Dim successorId As Integer = Convert.ToInt32(e.SuccessorNode.GetValue("Id"))
    If tasks.Contains(predecessorId) AndAlso tasks.Contains(successorId) Then
        e.Appearance.BackColor = DXSkinColors.FillColors.Warning
    End If
End Sub