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A Gantt widget is a complex component. One change can trigger a scala of updates. Furthermore You might want to rollback a change based on several factors. To allow this kind of behavior and to get around some of the Mendix pluggable widget API limitations the Gantt widget employs a custom sync. This has various implications. For one you do not need to refresh the entire list of objects just to refresh a single value in that list (which is the case for other Mendix widgets). As you can imagine, this greatly improves performance for large datasets. It might however take some getting used to so we recommend you take a look at our quick start application to see this in action.
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The synchronization flow involves quite a few steps and we therefore highly recommend you start with our quick start application instead of trying to to build everything on your own purely based on the documentation.
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Each individual list of crud objects (TaskCrud, DependencyCrud and AssignmentCrud) will need to be processed on the server. To do this you will need to loop over these lists and then split the subsequent action by it’s type (either updated, added or removed). Please see our quickstart application for an example on how to do this.
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