One of the first things that surprised me in SWT when I first used for client work about a decade and a half ago was that when writing multi-threaded code, I could not update GUI with normal method calls, yet I had to use Display.syncExec (or asyncExec). This has plagued me for many years and I always felt that an appropriate solution was missing, waiting to be discovered and implemented.
Thankfully, these days are over since Glimmer DSL for SWT just had a relatively major release in version 4.18.5.0, fully enabling a new option called auto_sync_exec
It basically detects if you are in a thread other than the main GUI thread and automatically calls sync_exec (the JRuby method syntax) for you when invoking SWT widget methods through Ruby meta-programming interception (a form of Aspect Oriented Programming). Otherwise, if you are in the main GUI thread or inside a larger sync_exec or async_exec call, it behaves normally.
This is implemented through a new method called auto_exec, which gets called behind the scenes, but could be used explicitly too just like sync_exec in case you'd like to have SWT batch a number of GUI updates together within a single `sync_exec` call.
Here is the blog post announcement for this Glimmer DSL for SWT version, which mentions other things such as the Canvas Shape DSL and the Hello, Tree! sample demonstrating one-line data-binding of tree (unheard of before)
https://andymaleh.blogspot.com/2021/02/glimmer-dsl-for-swt-hello-tree-and.html
Quick Example of Tree Data-Binding in Glimmer DSL for SWT (just one line of declarative data-binding code per property):
tree {
items bind(Employee, :ceo), tree_properties(children: :subordinates, text: :to_s)
selection bind(Employee, :selected_employee)
}
Basically, Employee.ceo is the root node of the tree. Children are fetched via the subordinates method and tree node text is fetched via the to_s method.
Happy Glimmering!
[Updated on: Tue, 23 February 2021 15:36] by Moderator
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