Moving JavaFX Nodes Between Stages - tabs

Question

I'm rewriting a Swing application in JavaFX, where I allow users to present multiple workspaces as either windows or tabs. However, my FX code will not display the contents moved from more than one tab into a new stage; only the contents of the currently-selected tab appear in my new stages. I've distilled my code into a small example below. Can anyone clue me in as to what's gone wrong?
package scenes;
import java.util.ArrayList;
import javafx.application.Application;
import javafx.application.Platform;
import javafx.scene.Scene;
import javafx.scene.control.Label;
import javafx.scene.control.Tab;
import javafx.scene.control.TabPane;
import javafx.scene.layout.BorderPane;
import javafx.stage.Stage;
public class StageSwapper extends Application {
static public void main(String[] args) {
launch(args);
}
private TabPane tabs = new TabPane();
public void start(Stage stage) {
stage.setTitle("Stage Swapper");
BorderPane p = new BorderPane();
p.setCenter(tabs);
tabs.getTabs().addAll(new Swapee("First").createTab(), new Swapee("Second").createTab());
Scene s = new Scene(p);
stage.setScene(s);
stage.show();
launchSwap();
}
private void launchSwap() {
new Thread() {
public void run() {
try {
sleep(10000);
} catch (Exception e) {
e.printStackTrace();
}
Platform.runLater(new Runnable() {
public void run() {
for (Swapee s : Swapee.list) {
createWindow(s);
}
}
});
}
}.start();
}
public void createWindow(Swapee s) {
Stage window = new Stage();
window.setTitle("New Window");
window.setY(200);
window.setX(200);
BorderPane p = new BorderPane();
p.setCenter(s);
window.setScene(new Scene(p));
window.show();
}
}
class Swapee extends Label {
static private int count;
static ArrayList<Swapee> list = new ArrayList<>();
String name;
Swapee(String name) {
super("Swappable Item " + ++count);
this.name = name;
list.add(this);
}
Tab createTab() {
Tab t = new Tab(name);
t.setContent(this);
return t;
}
}

Answer 1

You haven't specified the size of the windows that you're creating. Right now they have width and length equal to 0. You may use the following approach:
BorderPane p = new BorderPane();
p.setPrefSize(Region.USE_COMPUTED_SIZE, Region.USE_COMPUTED_SIZE);
p.setCenter(s);
BorderPane will be resized according to its content and the window will be resized as well.