var stopp = null var startt = null; var swapper = function(ov, old, running) { stopp.setVisible(running); startt.setVisible(!running); }; var runnerVp = null; function replaced() { /*if (runnerVp != null) { runnerVp["removeListener(javafx.beans.value.ChangeListener)"](swapper); }*/ runnerVp = base.getObservable("running"); runnerVp["addListener(javafx.beans.value.ChangeListener)"](swapper); startt = start; stopp = stop; if (typeof runnerVp == "boolean") { swapper(null, null, runnerVp.getValue()); } else { swapper(null, null, false); } } function run_command() { runnerVp.setValue(true); } function stop_command() { runnerVp.setValue(false); }