ListView appearing behind other graphical components in VBox

Question

I have created a ListView implementation of a ChoiceBox since I have a very long list of items and I don't like the fact that the entire list is displayed when opening the ChoiceBox. I have attached this ListView to a button so that when a user clicks on the button the ListView opens just like a ChoiceBox. My issue, however, is that when the ListView is diplayed it appears behind the other graphical components in my VBox container! I have tried to call "toFront()" on my ListView component however the VBox repositions my ListView component to the bottom of the VBox (which makes sense since toFront merely moves the node to the end of the VBox node list). Obviously this is not the behaviour I want and I don't want to have to convert my VBox to a StackPane (or just a Pane) and layout the components myself since the VBox lays out the components perfectly. It would be nice if there were a "z order" parameter but that doesn't appear to be the case and I have already looked into the "depth" parameter.
Are there any other ways to bring my ListView to the front without the VBox repositioning this component? How does the ChoiceBox component itself accomplish this? I have also tried to embed the ListView in a PopupControl but the unfortunate side effect of this is that the Popup always appears in front of EVERY window on my screen which is a tad annoying.
BTW, I think JavaFX is the next best thing to sliced bread! I have written a very large application and this is the only issue that I have run into since it went GA. JavaFX has far exceeded my expectations and the JavaFX team (and Oracle in general) and other developers who have contributed to this project should all be commended for the outstanding work they have done on this!!!

Answer 1

fermat wrote:
I have created a ListView implementation of a ChoiceBox since I have a very long list of items and I don't like the fact that the entire list is displayed when opening the ChoiceBox. I have attached this ListView to a button so that when a user clicks on the button the ListView opens just like a ChoiceBox. My issue, however, is that when the ListView is diplayed it appears behind the other graphical components in my VBox container! I have tried to call "toFront()" on my ListView component however the VBox repositions my ListView component to the bottom of the VBox (which makes sense since toFront merely moves the node to the end of the VBox node list). Obviously this is not the behaviour I want and I don't want to have to convert my VBox to a StackPane (or just a Pane) and layout the components myself since the VBox lays out the components perfectly. It would be nice if there were a "z order" parameter but that doesn't appear to be the case and I have already looked into the "depth" parameter.
Are there any other ways to bring my ListView to the front without the VBox repositioning this component? How does the ChoiceBox component itself accomplish this? I have also tried to embed the ListView in a PopupControl but the unfortunate side effect of this is that the Popup always appears in front of EVERY window on my screen which is a tad annoying.Ya, the PopupControl is the way to go with this. The reason why is that if you use "lightweight" rendering of the drop down (er... popup?) and it extends beyond the end of the window, you will have your list appear clipped. So you have to use a real heavyweight window (the PopupControl) to make sure that if it extends beyond the edge of the window, it displays correctly.
I believe the UI controls team is planning on adding a proper ComboBox (which, FWIW, we always planned to add) sometime between now and 3.0, but I'm not sure when. The ChoiceBox actually uses a ContextMenu, while ComboBox would use PopupControl, but some of the little details are the same. Here is a code snippet that might be useful from the ChoiceBox skin.
        // When popup is hidden by autohide - the ChoiceBox Showing property needs
        // to be updated. So we listen to when autohide happens. Calling hide()
        // there after causes Showing to be set to false
        popup.setOnAutoHide(new EventHandler<Event>() {
            @Override public void handle(Event event) {
                ((ChoiceBox)getSkinnable()).hide();
        // fix RT-14469 : When tab shifts ChoiceBox focus to another control,
        // its popup should hide.
        getSkinnable().focusedProperty().addListener(new ChangeListener<Boolean>() {
            @Override public void changed(ObservableValue<? extends Boolean> observable, Boolean oldValue, Boolean newValue) {
                if (!newValue) {
                    ((ChoiceBox)getSkinnable()).hide();
        // TODO remove this id once bug RT-7542 is fixed.
        popup.setId("choice-box-popup-menu");
BTW, I think JavaFX is the next best thing to sliced bread! I have written a very large application and this is the only issue that I have run into since it went GA. JavaFX has far exceeded my expectations and the JavaFX team (and Oracle in general) and other developers who have contributed to this project should all be commended for the outstanding work they have done on this!!!Dude, thanks for that, you just made my day :-)