Make an Event Start When Another Event Ends

With Preceden you can have one event start when another one ends. We call these events dependents because they depend on another event to determine their dates.

Specify a Dependency

Let's say you're a software developer using Preceden to plan the release of a new project.

In one of your layers you want two events, Alpha and Beta, representing where you and your team are in the development process.

For the Alpha phase, you add an event called Alpha with a start date of January 2018 and an end date of June 2018. For the Beta phase, say you estimate it will take 6 months. You have a few options for adding it to your timeline:

1. Fixed start and fixed end date - Add an event with a start date of June 2018 and an end date of November 2018.
2. Fixed start date with a duration - Add an event with a start date of June 2018 and an end date of 6 months.
3. Dependent start date with a fixed end date - Make Beta a dependent of Alpha and set the end date to November 2018.
4. Dependent start date with a duration - Make Beta a dependent of Alpha with an end date of 6 months.

The last option is my preference. You never have to enter Beta's start date, and it changes on its own if you ever change the dates for Alpha, the event it depends on. Giving Beta a duration rather than a fixed end date means its end date is recalculated too, every time its start date moves.

Here's how to do it:

When you add an event, check the Dependent box above the Start Date field. The box appears once the timeline has at least one other event for this one to follow.

The Start Date field becomes a dropdown list of the timeline's other events, grouped by layer and sorted by date within each layer. Select the event this one should start after, either by scrolling the list or by typing part of its name into the Search box.

Fill in the rest of the event's details, then save your changes by clicking Add Event or Update Event.

When the Earlier Event Has No End Date

If the event you pick is a single point in time, with a start date and no end date, the dependent starts on that date.

Chains of Dependents

A dependent can have dependents of its own. In the example above, a Release event could start when Beta ends. Change Alpha's dates and both Beta and Release move with it. Preceden won't save a dependency that loops back on itself, such as making Alpha start when Release ends.

Stop an Event Depending on Another

Open the event, uncheck Dependent, and type a date into the Start Date field that reappears. Then click Update Event.

Delete an Event That Has Dependents

If you delete an event that has dependents, Preceden gives each dependent a fixed start date matching the deleted event's end date (or its start date, if it had no end date).