windowsforms-devexpress-dot-xtrascheduler-dot-reporting-dot-timelinescaleheaders.md
Enables timeline headers to be painted in a custom manner.
Namespace : DevExpress.XtraScheduler.Reporting
Assembly : DevExpress.XtraScheduler.v25.2.Reporting.dll
NuGet Package : DevExpress.Win.SchedulerReporting
public event CustomDrawObjectEventHandler CustomDrawDayHeader
Public Event CustomDrawDayHeader As CustomDrawObjectEventHandler
The CustomDrawDayHeader event's data class is CustomDrawObjectEventArgs. The following properties provide information specific to this event:
| Property | Description |
|---|---|
| Bounds | Returns the bounding rectangle of the drawing area. |
| Cache | Gets an object which specifies the storage for the pens, fonts and brushes. Use it for custom painting in Scheduler Reports. |
| Graphics | Gets an object used for painting. |
| Handled | Gets or sets whether an event was handled. If it was handled, the default actions are not required. |
| ObjectInfo | Gets information on the painted element. |
The event data class exposes the following methods:
| Method | Description |
|---|---|
| DrawDefault() | Renders the element using the default drawing mechanism. |
| DrawHtml(HtmlTemplate, DxHtmlPainterContext, Action<DxHtmlPainterArgs>) | Paints the required HTML template inside an element that raised this event. The context parameter allows you to assign an object that transfers mouse events to template elements. |
| DrawHtml(HtmlTemplate, Action<DxHtmlPainterArgs>) | Paints the required HTML template inside an element that raised this event. |
| GetDisplayValue(String) | |
| GetValue(String) |
The CustomDrawDayHeader event is raised before an instance of the TimelineScaleHeaders is printed. The event parameter’s CustomDrawObjectEventArgs.ObjectInfo property provides information on the visual element being painted. The return value of this property should be typecast to the DevExpress.XtraScheduler.Drawing.TimeScaleHeader type.
Note
Use the CustomDrawObjectEventArgs.Cache property to paint shapes, write a text and insert images. Do not use the CustomDrawObjectEventArgs.Graphics object in Scheduler Reports.
Set the CustomDrawObjectEventArgs.Handled property to true to prohibit default painting. Call the CustomDrawObjectEventArgs.DrawDefault method to perform the default drawing procedure if necessary.
The following code sample illustrates the use of the CustomDrawDayHeader event to draw a gradient fill using resource colors. The XtraSchedulerReport.GetResourceColorSchema method is used to obtain colors used to paint elements that belong to different resources.
using DevExpress.XtraScheduler.Drawing;
// ...
private void timelineScaleHeaders1_CustomDrawDayHeader(object sender,
DevExpress.XtraScheduler.CustomDrawObjectEventArgs e) {
TimeScaleHeader header = (TimeScaleHeader)e.ObjectInfo;
SchedulerColorSchema schema = GetResourceColorSchema(header.Resource);
header.Appearance.HeaderCaption.BackColor = schema.CellLight;
header.Appearance.HeaderCaption.BackColor2 = schema.Cell;
e.DrawDefault();
e.Handled = true;
}
Imports DevExpress.XtraScheduler.Drawing;
' ...
Private Sub timelineScaleHeaders1_CustomDrawDayHeader(ByVal sender As Object, _
ByVal e As DevExpress.XtraScheduler.CustomDrawObjectEventArgs) _
Handles timelineScaleHeaders1.CustomDrawDayHeader
Dim header As TimeScaleHeader = CType(e.ObjectInfo, TimeScaleHeader)
Dim schema As SchedulerColorSchema = GetResourceColorSchema(header.Resource)
header.Appearance.HeaderCaption.BackColor = schema.CellLight
header.Appearance.HeaderCaption.BackColor2 = schema.Cell
e.DrawDefault()
e.Handled = True
End Sub
See Also