DRD overview resizing fix

[jarekdanielak]

Proposed Changes

This pull requests fixes two problems I found when resizing DRD preview:

1. When resizing, diagram drop zone would trigger occasionally and flash.
2. When resizing on macOS, the default (unloaded image) icon would show next to the cursor.

Before:

Screen.Recording.2025-01-08.at.14.39.34.mov

After:

Screen.Recording.2025-01-08.at.14.40.03.mov

Checklist

To ensure you provided everything we need to look at your PR:

• Brief textual description of the changes present
• Visual demo attached
• Steps to try out present, i.e. using the @bpmn-io/sr tool
• Related issue linked via Closes {LINK_TO_ISSUE} or Related to {LINK_TO_ISSUE}

[jarekdanielak]

@philippfromme could you have a look on Windows?

[barmac]

It still flickers for a bit. But why does it work for the panels, but not for the overview? Do we have competing implementations?

Screen.Recording.2025-01-08.at.17.33.23.mov

[jarekdanielak]

The panels are using ResizableContainer, but this overview has its own implementation for draggable. I will check it can be reworked with ResizableContainer without too much hacking.

[jarekdanielak]

It seems our ResizableContainer is not really suited to hold another Canvas inside of it.

I had a brief look at how resizing is implemented in the panels and columns of DMN tables. They are both built without utilizing HTML Drag and Drop API. I think HTML dragging is not the best choice to build a resizable container, but rewriting it would have minimal benefit for UX.

I suggest we merge this small improvement and leave this topic for now. If you want to leave it untouched until somebody comes to give it a proper re-work, fine by me.

[barmac]

OK let's accept the state as is. The PR is already an improvement, even though it's not the perfect solution.

[philippfromme]

I think HTML dragging is not the best choice to build a resizable container, but rewriting it would have minimal benefit for UX.

I agee, we are using it mainly for historical reasons because this utility has been around for a long time.

For the resizable panels (e.g. properties panel) we're not using it anymore.