property Chart.OverviewVisible as OverviewVisibleEnum
Specifies whether the chart's overview layout is visible or hidden.

OverviewVisibleEnum An OverviewVisibleEnum expression that indicates whether the  chart's overview area is visible or hidden.
By default, the OverviewVisible property is exOverviewHidden ( 0 ), so the chart's overview portion is not visible. The overview layout/map It is a view that is displayed at the top of the control and shows the whole timeline, with all objects within its view (a high-level view). It displays a 'select' box (the light blue box) that the user can drag to any location within the overview and then that area of the chart is shown at normal scale within the chart view. Use the OverviewHeight property to specify the height in pixels, of the overview area. The OverviewBackColor property specifies the background color for the overview area. Use the OverviewSelBackColor property to change the visual appearance of the selection in the overview area. The OverviewToolTip property specifies the format of the tooltip being displayed when the cursor hovers the overview area. The OverviewLevelLines property indicates the index of the level that displays the grid lines in the overview area. If the Label property is empty, the unit is not displayed in the zooming scale, if the AllowOverviewZoom property is not exDisableZoom. The OverviewZoomCaption property indicates the caption being displayed in each zooming unit. The OverviewShowMarkTimeZones property shows the marked time-zones on the control's overview map.

The color to specify the bar in the overview area is determined as follows:

(The bar is represented into the control's overview only if its determined color is not -1)

The color to specify the time-zone in the overview area is indicates by the Color parameter of the MarkTimeZone method. The MarkTimeZone method may be used to highlights different parts of the chart by specifying the range of dates.

The following screen shot shows the overview part of the control ( the top zone ):

The following screen shot shows the overview part of the control ( the red zone ):