The timeline shows no bars

A WklGantt shows its task list, but the timeline next to it stays empty, shows a gray hint such as “Timeline: set StartField.” or red error text, or some tasks have no bar.

WKL Forms Object Library with WklGantt, in Form view, and in Design view with LivePreview.

The timeline draws a bar for a task only if the schedule can be built and the task has a start and either a finish or a duration:

• StartField isn't set (gray hint), or the field is empty for a task (that task has no bar, and TaskKind returns wgkNone).
• An additional source is only partly set up, for example DependencySource without PredecessorField and SuccessorField, or HolidaySource without HolidayField. The schedule can't be built, and the timeline shows the reason in red. The list keeps working.
• The tasks fall outside the period the timeline shows: ChartStart/ChartFinish exclude them, or the timeline has been scrolled away from them.

1. Open the designer (property sheet, Custom row, [...]) and go to the Tasks page. Choose the start field and either the finish field or the duration field. The page's status line tells you what's missing.
2. Read the red text in the timeline, or Issues in VBA (Debug.Print Join(Me!Gantt1.Object.Issues, vbCrLf)), and finish setting up the source it names on the Dependencies, Resources, or Calendar and scheduling page.
3. Clear ChartStart and ChartFinish, or choose Today on the timeline's shortcut menu and scroll; Ctrl+mouse wheel changes the zoom level.
4. In Design view, set LivePreview to Yes to see the data (Design view shows sample nodes instead of the data).