[REACT] CRITICAL: Bryntum Gantt displaying data with wrong dates, an impossible to drag tasks in the past

[clovisapp]

Hi Bryntum,

We have upgraded to Bryntum Gantt (gantt-thin package), and we face a major problem using the library:

1- dates are changed for no reason once they are passed to Bryntum react package (cf screenshot).
2- it's impossible to drag events (tasks) in the gantt before the first event / task (cf video in attachments)

[marcio]

Hey clovisapp,

Thanks for reaching out.

To confirm, is that behavior only happening on thin version? Could you please provide a runnable test case for us to debug what's causing this behavior?

[clovisapp]

@marcio

I fixed this wrong behavior using

projectConstraintResolution: "ignore"

inside the object of each event (or event children).

I think this should be a default using Bryntum. Recalculating dates automaticaly creates big users and technical implementation misunderstanding.

[marcio]

Hey clovisapp,

Thanks for sharing your solution and glad that it's working as you expected now.

Actually, most of the clients report that having the automatic calculation of dates inside our Gantt is a nice feature, but we'll keep an eye on the preference changing and consider making the ignore resolution the default one.

Thanks for the note.

[clovisapp]

@marcio

All the public Gantt softwares i've tested don't include these automatic calculation. I guess you made Bryntum a more complicate library to answer many needs, but i highly think bringing the simple and standard gantt behaviors to the library would fit a higher audience for implementation.

Cf the comparison here with videos: https://clovisteam.notion.site/Standard-Gantt-behaviors-comparison-02c8f8b1d78345bab928670aae89a318?pvs=4

[mats]

Thanks for your feedback! The underlying logic here is that the Gantt won't let you drag tasks earlier than the project start date.

All the public Gantt softwares i've tested don't include these automatic calculation.

Notion/Asana are simplistic Gantt charts, yes. We are intentionally aligning more with what MSP / Primavera are doing. But I think it would be interesting to also offer alignment with simpler tools. We will discuss internally to see if we can add a new simplistic mode. If you have more feedback regarding discrepancies with Notion/Asana, please share and we'll review it.