JavaFX how to inject new FXML content to current Scene - java

I have an app, which has HomeScene.fxml file with headers and menu. HomeScene has also dashboardPane, which should be changed dynamically after menu button is being pressed. Dashboard pane content should be loaded from another fxml file, lets say 'FinancesPane.fxml' or 'SettingsPane.fxml'.
Im trying to replace content of dashboardPane in HomeController:
#FXML
public void handleFinancesButtonAction() {
FinancesPaneFactory paneFactory = new FinancesPaneFactory();
dashBoardPane.getChildren().clear();
dashBoardPane.getChildren().add(paneFactory.createPane());
}
My FinancesPaneFactory looks like this:
public class FinancesPaneFactory extends PaneFactory {
private static final String PANE_TEMPLATE_PATH = "/sceneTemplates/FinancesPane.fxml";
public FinancesPaneFactory() {
super(PANE_TEMPLATE_PATH );
}
#Override
protected Pane generatePane(FXMLLoader loader) {
try {
return (Pane) loader.load();
} catch (IOException e) {
throw new FatBirdRuntimeException("Unable to load FinancesPane", e);
}
}
}
To be more clear, this is how HomeScene looks like: HomeScene .
This empty space is a dashboardPane, and should be replaced with another content when user press the left menu button.
How to inject this content dynamically?

Yes, you should do this to keep scene graph low and you will benefit from better performance , what i do is create dynamic container :
#FXML
private ScrollPane dynamicNode;
Scroll pane is a good choice.
This is put to MainController.
I have main controller different from others , main controller is actually the only one i initialize, so in your main program class whatever you call it :
private static MainViewController mainViewController;
...
private static BorderPane loadMainPane() throws IOException {
FXMLLoader loader = new FXMLLoader();
loader.setController(mainViewController);
BorderPane mainPane = (BorderPane) loader.load(
CsgoRr.class
.getResourceAsStream(Info.Resource.FXML_FILE_MAIN));
mainPane.getStylesheets().add(CsgoRr.class.getResource("path...style.css").toString());
return mainPane;
}
Dont forget to create static accessor, other controllers that i have are usually not created this way , i use fx:controller in fxml to specify what controller should be for which fxml , its usually handy to have mainController accessable.
So to change your views create in your main controller methods that are connected to your menu with whose you change views
#FXML
private void setViewPreferences() {
setView(Info.Resource.FXML_FILE_PREFERENCES);
}
#FXML
private void setViewProductPage() {
setView(Info.Resource.FXML_FILE_PRODUCT_PAGE);
}
Currently in dynamicNode is helper to see what exactly is the current selected, its
private String currentlyInDynamicPane;//not important
Here is setView
public void setView(String fxmlPath) {
dynamicNode.setContent(getView(fxmlPath));
currentlyInDynamicPane = fxmlPath;
}
public Node getView(String fxmlPath) {
try {
return new FXMLLoader(getClass().getResource(fxmlPath)).load();
} catch (IOException ex) {
ex.printStackTrace();
return null;
}
}
So when you click left menu you swap FXML files, you can make sure that you have some default FXML shown at the start or when nothing in menu is selected as well.
This is the way i do it, roughly.
So think about YOUR DASHBOARD as DynamicPane,

Related

Cannot invoke the presenter because it is null, MVP architecture with JavaFX [duplicate]

I am having the following problem with a program that I am currently writing, and I have searched on the internet, but I couldn't really find anything to help me understand the following problem
So inside another class I have written a method that executes this whenever the search button is clicked and the method looks like this:
public void searchButton(){
try {
new SearchController().display();
} catch (IOException e) {
e.printStackTrace();
}
}
And then the SearchController class looks something like this (I simplified it here):
public class SearchController {
#FXML
private Button cancelButton;
#FXML
private Label what;
private static Stage stage;
private static BorderPane borderPane;
#FXML
public void initialize(){
what.setText("Testing"); // this woks
cancelButton.setOnAction(e -> stage.close());
}
public void display() throws IOException {
stage = new Stage();
stage.setResizable(false);
stage.setTitle("Product search");
stage.initModality(Modality.APPLICATION_MODAL);
FXMLLoader loader = new FXMLLoader();
loader.setLocation(SearchController.class.getResource("Search.fxml"));
borderPane = loader.load();
Scene scene = new Scene(borderPane);
stage.setScene(scene);
//what.setText("Testing") and this doesn't work
stage.showAndWait();
}
}
Can someone please tell me why it is possible to write text on the initialize method (that method gets called after the borderPane = loader.load(); line...so why doesn't it work if I try to write on the label after that line?)
Thank you in advance
The FXMLLoader creates an instance of the class specified in the fx:controller attribute of the FXML root element. It then injects the elements defined in the FXML file into the controller instance it created when the fx:id attributes match the field names. Then it calls the initialize() method on that instance.
You create an instance of the controller "by hand" with new SearchController(). This is not the same object that is created by the FXMLLoader. So now when you have loaded the fxml file you have two different instances of SearchController. So if you call what.setText(...) from the display() method, you are not calling it on the controller instance created by the FXMLLoader. Consequently, what has not been initialized in the instance on which you are calling what.setText(...), and you get a null pointer exception.
Since initialize() is invoked by the FXMLLoader on the instance it created, when you call what.setText(...) from the initialize() method, you are calling it on the instance created by the FXMLLoader, and so the FXML-injected fields for that instance have been initialized.

How to keep changes in FXML files when switching scenes

in our semester project we are working on world of zuul,
the problem is with the GUI part(JavaFX)
the problem is when we change "rooms" and lets say pick up an item when you go away from the room and go back to previous room the item is back.
so the problem is we initialize the FXML file anew each time.
the way we change rooms:
a small edit:
public class StartGame extends Main {
#FXML private Button start;
#FXML
public void onStart(MouseEvent event) {
//works this way
Parent loader = XMLLoader.load(getClass().getResource("station.fxml"));
// does not work O_o
Parent loader = getScene("station");
Stage stage = (Stage) start.getScene().getWindow();
stage.setScene(new Scene(loader, 731, 439))
}
}
public class Main extends Application {
HashMap<String, Parent> scenes = new HashMap<>();
public void start(Stage stage) {
Parent station = FXMLLoader.load(getClass().getResource("station.fxml"));
scenes.put("station", station);
Stage stage = FXMLLoader.load(getClass().getResource("startGame.fxml"));
stage.show();
}
public Parent getScene(String roomName) {
return this.scenes.get(roomName);
}
}
but when i try to use the getScene() method i get all sorts of erros, is this a smart way of trying to save changes when switching between FXML files or is there a better way?..that actually works

How can I get TextField from inner stage in JavaFX?

I have written a controller for two windows /stages.
The first window is opened in the MainClass. The second in the Controller, if the user clicks onto a button.
How can I get the TextFields from second.fxml in the applyFor()-method?
Thanks.
#FXML
protected void requestNewAccount(ActionEvent event) {
try {
FXMLLoader fxmlLoader = new FXMLLoader(getClass().getResource("second.fxml")); // TextFields in there
Parent root = (Parent) fxmlLoader.load();
Stage stage = new Stage();
stage.initModality(Modality.APPLICATION_MODAL);
stage.setTitle("Second Window");
Scene scene = new Scene(root);
String css = MainOnlineCustomer.class.getResource("/style.css").toExternalForm();
scene.getStylesheets().clear();
scene.getStylesheets().add(css);
stage.setScene(scene);
stage.show();
} catch (IOException e) {
logger.error(e);
}
}
/**
* closes the "second"-Window
* #param event
*/
#FXML
protected void cancel(ActionEvent event) {
final Node source = (Node) event.getSource();
final Stage stage = (Stage) source.getScene().getWindow();
stage.close();
}
#FXML
protected void applyFor(ActionEvent event) {
// get values from TextField in second.fxml here!!!
}
It's not good to share controllers between fxmls unless they serve the same purpose. Here both fxml seem to serve a different purpose (account management, login or something similar for one of them and creating a new account for the other). What is even worse is that those classes do not share the same controller instance, which means the small (and probably only) benefit you could get from using the same controller, is not used here. You should better use different controllers.
Since you use Modality.APPLICATION_MODAL as modality, I'd recommend using showAndWait instead of show to open the new stage. This will enter a nested event loop, which allows the UI to remain responsive and continues after the invocation of showAndWait once the stage is closed.
Furthermore add a method to the controller of second.fxml that allows you to retrieve the result.
Example
This creates a Person object with given name and family name.
"primary window (opening the "inner" stage)
FXMLLoader loader = new FXMLLoader(getClass().getResource("second.fxml"));
Stage subStage = new Stage();
subStage.initModality(Modality.APPLICATION_MODAL);
subStage.setTitle("Second Window");
Scene scene = new Scene(loader.load());
subStage.setScene(scene);
subStage.showAndWait();
Optional<Person> result = loader.<Supplier<Optional<Person>>>getController().get();
if (result.isPresent()) {
// do something with the result
}
controller for "inner" content
public class SecondController implements Supplier<Optional<Person>> {
#FXML
private TextField givenName;
#FXML
private TextField familyName;
private boolean submitted = false;
// handler for submit action
#FXML
private void submit() {
submitted = true;
givenName.getScene().getWindow().hide();
}
// handler for cancel action
#FXML
private void cancel() {
givenName.getScene().getWindow().hide();
}
#Override
public Optional<Person> get() {
return submitted ? Optional.of(new Person(givenName.getText(), familyName.getText())) : Optional.empty();
}
}
Note that you can gain access to any data available to the controller this way. I wouldn't recommend accessing any nodes (like TextFields) directly though, since this makes changing the UI harder.
Using the Supplier interface here is not necessary, but I chose to do this to achieve a loose coupling between SecondController and the main window.

JavaFX - Manage Objects between Tabs

I have a Controller, let's call it GeneralController, that creates a TabPane as well as two new tabs. The new tabs all get their own controller, "Tab1Controller" and "Tab2Controller".
Within the GeneralController, I create an Object "MyObject". This Object contains some data, that can be modified within Tab1Controller and Tab2Controller.
So far, so good.
"Tab1Controller" and "Tab2Controller" both have a initController function, which gets "MyObject" as a parameter. This way, I can initalize both Controllers with "MyObject".
GeneralController:
// Similar function for Tab2Controller
private void createTab1(ObjectProperty<MyObject> myObject) {
try {
FXMLLoader loader = new FXMLLoader();
loader.setLocation(Main.class.getResource("path/to/tab1.fxml"));
Tab tab1 = (Tab) loader.load();
Tab1Controller tab1Controller = loader.getController();
tab1Controller.initController(myObject)
generalTabs.getTabs().add(tab1);
}
catch (IOException ex) {
ex.printStackTrace();
}
}
Tab1Controller/Tab2Controller:
public void initController(ObjectProperty<MyObject> myObject) {
this.myObject = myObject;
}
Here comes my question:
How do I ensure in the best way, that I keep my Labels, Controls, Nodes, Charts, whatever, up-to-date within Tab1Controller and Tab2Controller?
Is it reasonable to create a setOnSelectionChanged-Listener in Tab1Controller and Tab2Controller, and update all possible data-changes?
A good solution would be using the observer pattern.
If you need a good example, take a look at this

Java Form problems

I've recently delved into JavaFX as a C# developer. One thing I noticed in Java is that you're not spoon fed the way Visual Studio/Microsoft spoonfeed us.
So. When I was creating a form using the scene builder for IntelliJ Idea on JavaFX. I inherited "Stage" for my controller class and created a void called load that will load the instance of the scene from the FXML file. Therefore when I call load() from the Main entry point or anywhere it will load the fxml file and show.
LoginController frmLogin = new LoginController();
frmLogin.load();
The problem is that it works and it does't work.
Here's my code.
Main.Java
public class Main extends Application
{
#Override
public void start(Stage primaryStage) throws Exception
{
LoginController frmLogin = new LoginController();
frmLogin.load();
}
public static void main(String[] args)
{
Application.launch(args);
}
}
LoginController.Java
public class LoginController extends Stage
{
#FXML
private TextField txtUsername;
#FXML
private TextField txtPassword;
#FXML
private void btnLogin_Clicked(ActionEvent e) throws Exception
{
if (txtUsername.getText().equals("admin") && txtPassword.getText().equals("pass"))
{
Messagebox.Show("Correct Login!");
this.show(); //The problem occurs here!
}
else
{
Messagebox.Show("Incorrect Login");
}
}
public void load() throws Exception
{
Parent root = FXMLLoader.load(getClass().getResource("frmLogin.fxml"));
this.setScene(new Scene(root));
this.setTitle("JavaFX GUI");
this.setResizable(false);
this.initModality(Modality.APPLICATION_MODAL);
this.show();
}
}
Here's a GIF of the problem.
http://i.imgur.com/0hOG76M.gif
I want to know why when I call .show() it shows a blank for?
Any help would be appreicated.
Solution
Don't inherit Stage in your Controller.
JavaFX will implicitly create a Stage for your application and pass it to your application (the primaryStage parameter in your application start method).
Sample
Here is a quick update which should work. Another alternative for this is to factor out the stage management as in James's answer.
public class Main extends Application
{
#Override
public void start(Stage primaryStage) throws Exception
{
Parent root = FXMLLoader.load(getClass().getResource("frmLogin.fxml"));
primaryStage.setScene(new Scene(root));
primaryStage.setTitle("JavaFX GUI");
primaryStage.setResizable(false);
primaryStage.show();
}
public static void main(String[] args)
{
Application.launch(args);
}
}
. . .
public class LoginController
{
#FXML
private TextField txtUsername;
#FXML
private TextField txtPassword;
#FXML
private void btnLogin_Clicked(ActionEvent e) throws Exception
{
if (txtUsername.getText().equals("admin") && txtPassword.getText().equals("pass"))
{
Messagebox.Show("Correct Login!");
}
else
{
Messagebox.Show("Incorrect Login");
}
}
}
Aside: I am not sure what your MessageBox class is, but JavaFX 8u40 has a built-in Alert dialog box for standard message box style functionality, so that would be the preferred method to do that.
It looks like you have confused the different pieces that make up the application.
The FXML typically represents the "view"; i.e. the portion of the UI that is visible. It defines what controls are displayed and how they are laid out.
The controller implements the logic that is connected to (controls) the view. So it typically processes user input and updates the view in various ways.
A Stage is a window.
So, I don't think it really makes sense that your controller is a Stage. There are some scenarios where you might make a controller a subclass of a UI element, but those are somewhat advanced uses of JavaFX, and even then you would typically subclass a layout pane, not a Stage.
Here's roughly what happens when you call load on an FXMLLoader:
The FXMLLoader creates a hierarchy of Nodes (UI elements) corresponding to the elements defined in the FXML file
If the FXML file defines a fx:controller attribute in its root element, the FXMLLoader constructs a new instance of that class. It then injects any elements with fx:id attributes into fields in that controller instance with names matching the fx:id values. It also registers any event handlers mapping to methods in the controller instance.
The FXMLLoader's load() method returns the object corresponding to the root element of the FXML file.
So, in your code, you actually end up with two LoginController instances. You create one yourself in the start() method. You then call load() on that instance. That method calls load(...) on an FXMLLoader (via the really ugly static load method). Calling FXMLLoader.load(...) then causes the FXMLLoader to create an instance of the class declared in fx:controller. I'm guessing (you didn't show the FXML code) that class is also LoginController. So that is the second instance.
Now what happens, is that you get a reference to the UI element from FXMLLoader.load(). You put that in a Scene, and set the Scene in the LoginController, which - unusually - is a Stage. Then you make the Stage appear on the screen with show(). Note this happens in the instance you created in the start method.
When the user presses the button that has btnLogin_Clicked registered as its handler, the handler method is invoked on the controller instance: the one created by the FXMLLoader. That instance never had a Scene set, so when you then call this.show() it shows that instance of the LoginController (which, again, is a Stage). Since it never had its scene set, you see a blank window.
It's not actually clear to me what you intend with the call to this.show() in btnLogin_Clicked anyway. Assuming you thought this was the same Stage you had created from the start(...) method, that Stage is already showing.
The typical pattern is that you use the primaryStage that is passed to the start(...) method, and set a scene in that and show it. So you'd do something like:
public class Main extends Application
{
#Override
public void start(Stage primaryStage) throws Exception
{
Parent root = FXMLLoader.load(getClass().getResource("frmLogin.fxml"));
primaryStage.setScene(new Scene(root));
primaryStage.setTitle("JavaFX GUI");
primaryStage.setResizable(false);
primaryStage.initModality(Modality.APPLICATION_MODAL);
primaryStage.show();
}
public static void main(String[] args)
{
Application.launch(args);
}
}
and then the controller is just a controller: it just handles the logic:
public class LoginController
{
#FXML
private TextField txtUsername;
#FXML
private TextField txtPassword;
#FXML
private void btnLogin_Clicked(ActionEvent e) throws Exception
{
if (txtUsername.getText().equals("admin") && txtPassword.getText().equals("pass"))
{
Messagebox.Show("Correct Login!");
// I don't really know what you were trying to do here
// but if you need a reference to the window containing the
// associated fxml elements, you can get it from one of those
// elements:
Stage stage = (Stage) txtUsername.getScene().getWindow();
//this.show(); //The problem occurs here!
}
else
{
Messagebox.Show("Incorrect Login");
}
}
}
Typically what you want to do when the user has successfully logged in, is to display something new in the current window. The simplest way to do this is just to set the root of the current scene to the content of a different FXML file. For example:
public class LoginController
{
#FXML
private TextField txtUsername;
#FXML
private TextField txtPassword;
#FXML
private void btnLogin_Clicked(ActionEvent e) throws Exception
{
if (txtUsername.getText().equals("admin") && txtPassword.getText().equals("pass"))
{
Messagebox.Show("Correct Login!");
Scene currentScene = txtUsername.getScene();
Parent root = FXMLLoader.load(getClass().getResource("Main.fxml"));
currentScene.setRoot(root);
// resize window:
currentScene.getWindow().sizeToScene();
}
else
{
Messagebox.Show("Incorrect Login");
}
}
}
Here Main.fxml defines the main application the user sees, having successfully logged in, and defines its own controller class, etc.

Categories