Get Active Shell in SWT, even if the Shell is not on focus
Recently, I had a similar problem and though you probably found a solution in the meanwhile, I'd like to share mine for future reference.
The ShellActivationTracker adds a display filter that listens for Activate events and - if the activated widget is a Shell - remembers the most recently activated Shell. Thus you can query the (last) active shell even if your application is currently not active/focused.
class ShellActivationTracker implements Listener { Shell activeShell; ShellActivationTracker(Display display) { activeShell = display.getActiveShell(); display.addFilter(SWT.Activate, this); } @Override public void handleEvent(Event event) { if (event.widget instanceof Shell) { activeShell = (Shell)event.widget; } }}