linker85 linker85 - 5 months ago 13
Java Question

why am I getting java.lang.IllegalStateException on javafx?

I have an application that has a

TableView
that has an attached listener so it refreshes as soon as it detects a change, but the thing is that I´m getting
java.lang.IllegalStateException: Not on FX application thread; currentThread = Smack Listener Processor (0)
.
Here is my code:

/**
* This function resets the pagination pagecount
*/
public void resetPage() {
try {
System.out.println("RESET");
int tamRoster = this.loginManager.getRosterService().getRosterList().size();
paginationContactos.setPageCount((int)(Math.ceil(tamRoster*1.0/limit.get())));
int tamEnviados = this.loginManager.getRosterService().getEnviadasList().size();
paginationEnviadas.setPageCount((int)(Math.ceil(tamEnviados*1.0/limit.get())));
int tamRecibidas = this.loginManager.getRosterService().getRecibidasList().size();
paginationRecibidas.setPageCount((int)(Math.ceil(tamRecibidas*1.0/limit.get())));
} catch (Exception e) {
e.printStackTrace();
}
}

public void doSomething () {
this.loginManager.getRosterService().getRosterList().addListener(new ListChangeListener<RosterDTO>() {
@Override
public void onChanged(
javafx.collections.ListChangeListener.Change<? extends RosterDTO> c) {
// TODO Auto-generated method stub
resetPage();
while (c.next()) {
if (c.wasPermutated()) {
System.out.println("PERM");
} else if (c.wasUpdated()) {
System.out.println("UPD");
} else {
System.out.println("ELSE");
}
}
}
});
}


Altough it enters the resetPage method, I get that exception.
Why is this happening?
How can I fix it?
Thanks in advance.

Answer

Indeed, MohamedSanaulla is right you can't update the UI from a thread that is not the application thread. But still, if you really want to modify your UI from a different thread use the Platform.runlater(new Runnable()) method. And put your modifications inside the Runnable object.

Example :

Platform.runLater(new Runnable() {
    @Override
    public void run() {
        //if you change the UI, do it here !
    }
});