binding - Clojure and JavaFX 2.0 -- How to access element's ID from clojure callback function -

following javafx tutorial here: http://docs.oracle.com/javafx/2/get_started/fxml_tutorial.htm, trying make run in clojure. i'm doing lein run after setting :aot :all , stuff (:gen-class) etc. took few days of figuring out, seems working.

in src/jfxtwo/clojureexamplecontroller.clj:

(defn -handlesubmitbuttonaction [^actionevent event]   (let [actiontarget (text.)]     (println "event button pressed")     (println "event instance:" event)     (println "event class:" (class event))     (.settext actiontarget "sign in button pressed..."))) 

in resources/fxml_example.fxml:

<gridpane fx:controller= "jfxtwo.clojureexamplecontroller"       xmlns:fx= "http://javafx.com/fxml"        alignment= "center" hgap= "10" vgap= "10"       styleclass= "root" > ...     <button text= "sign in"     onaction= "#handlesubmitbuttonaction" />  ...     <text fx:id= "actiontarget"         gridpane.columnindex= "1" gridpane.rowindex= "6" /> ... 

i have clojure code able read fxml , css file generate proper gui. when press button can see event handler being called, don't know how access text want change, or actionevent instance associated button press. tried (println event) , (println (class event)) expecting see actionevent instance, results in showing me whatever reason callback function thinks event clojureexamplecontroller, though type hint says should actionevent:

event button pressed event instance: #<clojureexamplecontroller jfxtwo.clojureexamplecontroller@3e61061d> event class: jfxtwo.clojureexamplecontroller 

the java code looks this:

public class jfxappsamplecontroller  {    @fxml private text actiontarget;    @fxml protected void handlesubmitbuttonaction(actionevent event) {        actiontarget.settext("sign in button pressed");    } } 

clearle @fxml annotation doing magic here. what's going on, , how make work in clojure?

also, there way bind button press text change directly in fxml don't have handle gui->gui change in code-behind, , instead deal logic associated button press? i'm guessing yes, haven't gotten point in tutorial.

thanks!

you need explicit this argument in handler:

(defn -handlesubmitbuttonaction [this ^actionevent event]   ...) 

perhaps more accurate way of putting event is this argument in handler exhibited in question text , need add second argument accept event in , move type hint (and rename first argument this readability).

given fact code gets called @ all, seem javafx happy call handler without passing event @ if doesn't care (as evidenced not having formal parameter corresponding it).

the type hint's purpose allow clojure compiler avoid emitting reflective code when actionevent methods called on event. not prevent passing object of different type function.