Bi-directional (BiDi) language support is one of the rare areas where eSWT acts different from the desktop SWT. Mobile phones are personal devices where it is desired that the language selected for the device determines the language for the applications. On the other hand, it is more common on desktop PCs that some applications, and IDEs especially fall into this category, are desired to have a different language support than the platform’s selected language.
BiDi support in SWT and eSWT is specified to be supported through the use of SWT.RIGHT_TO_LEFT flag on Control creation. The difference on eSWT is it really does not. eSWT implementations currently do not support explicitly setting of the SWT.RIGHT_TO_LEFT flag on Controls. So it is not possible to force orientation on eSWT Controls at this time. There are currently plans to support these flags in the future on platforms where it is possible.
The second difference is the default orientation. eSWT implementations inherit the language direction from user selected language of the device. That means, on a mobile phone that has Urdu as the selected language, the orientation will be right to left. This is different from SWT where directionality is determined by use of command line parameters or system properties as explained in here. There are also plans to support a system property to determine the default language direction for eSWT. Of course, such a property will not make too much difference in platforms such as MIDP but it can get handy for eRCP applications.