javafx previous tabs affect newest tab - javafx

Question

Everything works fine until I create a new tab. Then when I go to the previous and try to use any of the buttons they affect the latest tab not the one I have selected. But if I go to the latest tab it works like normal. Here is the class that I use to make my tabs. So, why is the previous tabs affecting the lastest? And how do I fix it?
public class JTab {
private javafx.scene.control.Tab tab;
private ImageView imgView;
private Image logo;
private BorderPane root;
private Button reloadButton, backButton, forwardButton;
private TextField field;
private WebView view;
private WebEngine engine;
private static JTab instance;
private JBrowser jBrowser;
private JTab(JBrowser jBrowser) {
this.jBrowser = jBrowser;
}
public static JTab getInstance(JBrowser browser) {
if(instance == null)
instance = new JTab(browser);
return instance;
}
public javafx.scene.control.Tab addTab() {
tab = new Tab();
tab.setText("New Tab");
tab.setOnClosed(event2 -> {
if(jBrowser.getTabPane().getTabs().size() == 1) {
jBrowser.getTabPane().setTabClosingPolicy(TabPane.TabClosingPolicy.UNAVAILABLE);
}
});
logo = new Image("unknown-document.png");
imgView = new ImageView(logo);
tab.setGraphic(imgView);
HBox hBox = new HBox(5);
hBox.setAlignment(Pos.CENTER);
reloadButton = new Button("Reload");
backButton = new Button("<");
forwardButton = new Button(">");
reloadButton.setOnAction(event1 -> engine.reload());
backButton.setOnAction(event1 -> loadData(goBack()));
forwardButton.setOnAction(event1 -> loadData(goForward()));
//The TextField for entering web addresses.
field = new TextField("Enter URL");
field.setPrefColumnCount(50); //make the field at least 50 columns wide.
field.focusedProperty().addListener((ObservableValue<? extends Boolean> ov, Boolean t, Boolean t1) -> { //When click on field entire thing selected
Platform.runLater(() -> {
if (field.isFocused() && !field.getText().isEmpty()) {
field.selectAll();
}
});
});
field.setOnKeyPressed(event -> { //When ENTER is pressed it will load page
if (event.getCode() == KeyCode.ENTER) {
if (!field.getText().isEmpty()) {
loadData(field.getText());
}
}
});
//Add all out navigation nodes to the vbox.
hBox.getChildren().addAll(backButton, forwardButton, reloadButton, field);
view = new WebView();
engine = view.getEngine();
engine.setJavaScriptEnabled(true);
engine.getLoadWorker().stateProperty().addListener(
(ov, oldState, newState) -> {
if (newState == Worker.State.SUCCEEDED) {
tab.setText(getTitle());
//TODO setGraphic
}
});
loadData("google.com");
root = new BorderPane();
root.setPrefSize(1024, 768);
root.setTop(hBox);
root.setCenter(view);
tab.setContent(root);
return tab;
}
public void loadData(String URL) {
if(!URL.startsWith("http://")) {
URL = "http://" + URL;
}
field.setText(URL);
tab.setText(URL);
engine.load(URL);
}
private String getTitle() {
Document doc = engine.getDocument();
NodeList heads = doc.getElementsByTagName("head");
String titleText = engine.getLocation() ; // use location if page does not define a title
if (heads.getLength() > 0) {
Element head = (Element)heads.item(0);
NodeList titles = head.getElementsByTagName("title");
if (titles.getLength() > 0) {
Node title = titles.item(0);
titleText = title.getTextContent();
}
}
return titleText;
}
private String goBack() {
final WebHistory history = engine.getHistory();
ObservableList<WebHistory.Entry> entryList = history.getEntries();
int currentIndex=history.getCurrentIndex();
Platform.runLater(() -> history.go(-1));
return entryList.get(currentIndex>0?currentIndex-1:currentIndex).getUrl();
}
private String goForward() {
final WebHistory history = engine.getHistory();
ObservableList<WebHistory.Entry> entryList=history.getEntries();
int currentIndex=history.getCurrentIndex();
Platform.runLater(() -> history.go(1));
return entryList.get(currentIndex<entryList.size()-1?currentIndex+1:currentIndex).getUrl();
}
}

Answer 1

Remove getInstance(jBrowser) method
Make the constructor public.
Then to add a tab to a tabPane do
tabPane.getTabs().add(new JTab(jBrowser).addTab());