A new Widget Toolkit API
An issue that is partly related to the API question are LayoutManagers.
Why a new API at all?
- Low level (web) technologies should be hidden from the targeted developers (e.g. there should not be a WebComponent#getStyle() method to modify css styles directly)
- Layout algorithms are too basic to build a workbench upon.
Use the SWT API?
- Full binary compatibility
- Complete reuse of JFace
- SWT with its comprehensive set of widgets, 'dictates' the intial implementation effort. With another API we could start with a smaller subset of widgets.
- Hides the semantic differences between a client-side only and a distributed environment. E.g. it would be possible to implement a KeyListener, but since the event must go over the wire the user experience would be low.
- Probably won't meet the high expectations of RCP developers
- It is yet unclear how close we can get to the 'original' layout managers. From what we know by now a big challenge would be to compute the actual size of text (as used to determine the prefered size of a widget)
Use an SWT-like API?
To escape the downside of emulating the full SWT API, we could use a subset of SWT (like [eRCP http://www.eclipse.org/ercp]) and provide alternative/additional API where SWT does not meet the requirements of a distributed environment (in particular event handling).