My dashboard fxml location is Dashboard/DashBoardScene.fxml. I tried to switch from Login/LoginController to dashboard screen
public void onLoginButtonClick(ActionEvent actionEvent) throws IOException {
FXMLLoader fxmlLoader = new FXMLLoader(getClass().getResource("Dashboard/DashBoardScene.fxml"));
Parent root1 = (Parent) fxmlLoader.load();
Stage stage = new Stage();
stage.initModality(Modality.APPLICATION_MODAL);
stage.initStyle(StageStyle.UNDECORATED);
stage.setTitle("ABC");
stage.setScene(new Scene(root1));
stage.show();
}
but i got location is required error?
The code is in a class in the RestarantApp.Dashboard package (BTW, please use proper naming conventions). Your FXML file is in the same package.
The code getClass().getResource(...) will return a URL of a resource that is searched relative to the current class. Since the current class and the FXML file are in the same package, all you need is
FXMLLoader fxmlLoader = new FXMLLoader(getClass().getResource("DashBoardScene.fxml"));
(This assumes the FXML file is being deployed correctly, the resource name is spelled correctly, etc.)
You can also specify an "absolute" path (one that is relative to the classpath) to the resource:
FXMLLoader fxmlLoader = new FXMLLoader(getClass().getResource("/RestarantApp/Dashboard/DashBoardScene.fxml"));
Note here the path begins with a leading /.
Related
with the ScheneBuilder I defined the controller class of my fxml, the code genereted inside my AnchorPane tag is:
fx:controller="demo.SplashController"
now I would like if I had args in the main, to load a new version of the controller, using the appropriate construct. I try this code in the Application.start:
FXMLLoader loader = new FXMLLoader(getClass().getResource("page.fxml"));
PageController controller;
if(!dir.equals("")){ //attribute coming from args
controller = new PageController(dir);
}else{
controller = new PageController();
}
loader.setController(controller);
AnchorPane root = loader.load();
Scene scene = new Scene(root,480,414);
primaryStage.setScene(scene);
primaryStage.show();
but using this code a conflict appears because I have already defined the controller in my project with FXML code, to solve it would be enough to remove the segment in the FXML code but I would not do it because leaving the code in the fxml allows me to access some good features of the SceneBuilder.
The only way pass parameters to the controller's constructor and specify the controller's class in the fxml is to use a controller factory:
FXMLLoader loader = new FXMLLoader(getClass().getResource("page.fxml"));
loader.setControllerFactory(cl -> dir.isEmpty() ? new PageController() : new PageController(dir));
AnchorPane root = loader.load();
Another option would be to create a method in the controller class that allows you to pass the info after loading and does the initialisation:
FXMLLoader loader = new FXMLLoader(getClass().getResource("page.fxml"));
AnchorPane root = loader.load();
PageController controller = loader.getController();
controller.setDir(dir);
Note that the method call happens after the initialize method is run assuming there is one.
When creating the display in my main loop, the loader for an AnchorPane FXML returns null when getController() is called.
//instantiates the FXMLLoader class by calling default constructor
//creates an FXMLLoader called loader
FXMLLoader loader = new FXMLLoader();
//finds the location of the FXML file to load
loader.setLocation(mainApp.class.getResource("/wang/garage/view/ItemOverview.fxml"));
//sets the AnchorPane in the FXML file to itemOverview
//so that the AnchorPane is set to the display of the app
AnchorPane itemOverview = (AnchorPane) loader.load();
rootLayout.setCenter(itemOverview);
//finds the controller of the itemOverview and
//sets it to controller variable
//then provides a reference of mainApp to controller to connect the two
ItemOverviewController controller = loader.getController();//returns null
controller.setMainApp(this);
I did not specify the controller in the FXML document. Is this necessary if I am using loader.load()? If so, how should I specify the controller in the FXML document?
If you are not setting the controller in Java code directly, you need to specify the controller class in the FXML file (else the FXMLLoader will have no information as to what kind of object it is supposed to create to use as the controller).
Just add the
fx:controller="com.mycompany.myproject.ItemOverViewController
attribute to the root element of the FXML file in the usual way.
Alternatively, you can set the controller from Java:
//instantiates the FXMLLoader class by calling default constructor
//creates an FXMLLoader called loader
FXMLLoader loader = new FXMLLoader();
//finds the location of the FXML file to load
loader.setLocation(mainApp.class.getResource("/wang/garage/view/ItemOverview.fxml"));
// create a controller and set it in the loader:
ItemOverviewController controller = new ItemOverviewController();
loader.setController(controller);
//sets the AnchorPane in the FXML file to itemOverview
//so that the AnchorPane is set to the display of the app
AnchorPane itemOverview = (AnchorPane) loader.load();
rootLayout.setCenter(itemOverview);
//provide a reference of mainApp to controller to connect the two
controller.setMainApp(this);
I have a main FXML document for my program which contains a TabPane. For each tab I want it to have its own controller and fxml file. When I try to include the external fmxl files into the main fxml document, my program refuses to run. here is my main FXML document:
here is a copy of my java file
#Override
public void start(Stage stage) throws Exception {
FXMLLoader fxml = new FXMLLoader();
Parent root = fxml.load(getClass().getResource("FXMLDocument.fxml").openStream());
Scene scene = new Scene(root);
stage.setScene(scene);
stage.show();
FXMLDocumentController fdc = fxml.getController();
}
Error:
Caused by: javafx.fxml.LoadException: Base location is undefined. unknown path:97
This error is caused because you have not set the location property of the FXMLLoader, and instead you are specifying an InputStream from which to load the FXML. I think the FXMLLoader must need to know the location of the original fxml file in order to resolve the location of the included file. You should really only use the load(InputStream) method in exceptional circumstances: when you are loading the fxml from a source other than a resource (i.e. file or resource in your application jar file).
Instead, use
FXMLLoader fxml = new FXMLLoader();
fxml.setLocation(getClass().getResource("FXMLDocument.fxml"));
Parent root = fxml.load();
or, equivalently,
FXMLLoader fxml = new FXMLLoader(getClass().getResource("FXMLDocument.fxml"));
Parent root = fxml.load();
I have 2 fxml files:
Layout (header, menubars and content)
Anchorpane (it's supposed to be placed inside the content from the other fxml file)
I would like to know how can I load the second file inside the content space from the "Master" scene. And is that a good thing to do working in javaFX or is it better to load a new scene?
I'm trying to do something like this, but it doesn't work:
#FXML
private AnchorPane content;
#FXML
private void handleButtonAction(ActionEvent event) {
content = (AnchorPane) FXMLLoader.load("vista2.fxml");
}
Thanks for the help.
Why your code does not work
The loader creates a new AnchorPane, but you never add the new pane to a parent in the scene graph.
Quick Fix
Instead of:
content = (AnchorPane) FXMLLoader.load("vista2.fxml");
Write:
content.getChildren().setAll(FXMLLoader.load("vista2.fxml"));
Replacing the content children with your new vista. The content itself remains in the scene graph, so when you set it's children, you are also attaching them to the scene graph at the same time.
You might need to play around with layout (e.g. work with auto resizing layouts like StackPanes rather than AnchorPanes) to get the exact behaviour you want.
Rather than just adopting the quick fix, I would advise reviewing the simple framework linked below as that might provide you with a more general purpose mechanism to get the behaviour you want.
Reference FXML Navigation Framework
I created a small framework for swapping fxml controlled content panes in and out of a portion of the main scene.
The mechanism of the framework is the same as suggested in kithril's answer.
A main pane for the outer fxml acts as a holder for child panes.
The main controller for the outer fxml supplies a public method that can be used to swap the child panes.
A convenience navigator class is statically initialized with the main controller for the outer layout.
The navigator provides a public static method to load a new child pane into the main container (by invoking a method on the main controller).
Child panes are generated in the navigator by their respective fxml loaders.
Why a Framework
The framework seems like overkill for answering your question, and perhaps it is. However, I have found that the two most asked topic related to FXML are:
Navigation between panes generated by FXML (this question).
How to pass data between FXML controllers.
So I felt that a small demo framework was warranted for this case.
Sample Framework Output
The first screen shows the application layout displaying the first vista. The contents are a header which is defined in the main application layout and an aliceblue colored interchangable child content pane.
In the next screen, the user has navigated to the second vista, which retains the constant header from the main layout and replaces the original child pane with a new coral colored child content pane. The new child has been loaded from a new fxml file.
Looking for Something More Substantial?
A lightweight framework which is more extensive and better supported than the sample framework from this question is afterburner.fx.
Looking for Something Even Simpler?
Just swap out the scene root: Changing Scenes in JavaFX.
Other Options?
Animated Transitions and others: Switch between panes in JavaFX
Im not sure about how effective this is, but seems to be just fine and what's more, much simpler to methods above.
https://www.youtube.com/watch?v=LDVztNtJWOo
As far as I understood what is happening here is this(its really similiar to what is happening in Start() method in application class) :
private void buttonGoToWindow3Action(ActionEvent event) throws IOException{
Parent window3; //we need to load the layout that we want to swap
window3 = (StackPane)FXMLLoader.load(getClass().getResource("/ScenePackage/FXMLWindow3"));
Scene newScene; //then we create a new scene with our new layout
newScene = new Scene(window3);
Stage mainWindow; //Here is the magic. We get the reference to main Stage.
mainWindow = (Stage) ((Node)event.getSource()).getScene().getWindow();
mainWindow.setScene(newScene); //here we simply set the new scene
}
However Im not a java expert and quite new to programing so it would be good if someone experienced would evaluate it.
EDIT:
Ive found even simpler method;
Go to MainApplication class and make static Stage parentWindow.
public static Stage parentWindow;
#Override
public void start(Stage stage) throws Exception {
parentWindow = stage;
Parent root = FXMLLoader.load(getClass().getResource("/ScenePackage/FXMLMainScene.fxml"));
Scene scene = new Scene(root);
stage.setScene(scene);
stage.show();
}
Now you get acces to your main Stage so anywhere in a program you can do something like that to change the scene:
Parent window1;
window1 = FXMLLoader.load(getClass().getResource("/ScenePackage/FXMLWindow1.fxml"));
//Scene newSceneWindow1 = new Scene(window1);
Stage mainStage;
//mainStage = (Stage) ((Node)event.getSource()).getScene().getWindow();
mainStage = MainApplication.parentWindow;
mainStage.getScene().setRoot(newSceneWindow1); //we dont need to change whole sceene, only set new root.
Others may have a better solution, but my solution has been to have a simple container like VBox in the outer fxml, then load the new content and add it as a child of the container. If you're only loading one or two forms, this might be the way go to go. However, for a more complete framework, I found this blog post helpful: https://blogs.oracle.com/acaicedo/entry/managing_multiple_screens_in_javafx1 She has source code for her framework which includes fancy transitions. Although it's meant to manage top level scenes, I found it easy to adapt for managing inner content regions too.
My example of the mask.
Using:
Main.getNavigation().load(View2.URL_FXML).Show();
Main.getNavigation().GoBack();
In this case, I recommend you to use custom component instead. First create a custom component for your content:
class Content2 extends AnchorPane {
Content() {
FXMLLoader loader = new FXMLLoader(getClass().getResource("vista2.fxml");
loader.setRoot(this);
loader.setController(this);
loader.load();
}
}
Replace the AnchorPane markup in the root of your vista2.fxml file with fx:root:
<fx:root type="javafx.scene.layout.AnchorPane" xmlns:fx="http://javafx.com/fxml">
...
</fx:root>
Then, you can do this simply by using custom event binding and arrow function. Add event handler property to your Content class:
private final ObjectProperty<EventHandler<ActionEvent>> propertyOnPreviousButtonClick = new SimpleObjectProperty<EventHandler<ActionEvent>>();
#FXML
private void onPreviousButtonClick(ActionEvent event) {
propertyOnPreviousButtonClick.get().handle(event)
}
public void setOnPreviousButtonClick(EventHandler<ActionEvent> handler) {
propertyOnPreviousButtonClick.set(handler);
}
Finally, bind your custom event handler in your java code or fxml:
#FXML
onNextButtonClick() {
Content2 content2 = new Content2();
content2.setOnPreviousButtonClick((event) -> {
Content1 content1 = new Content1();
layout.getChildren().clear();
layout.getChildren().add(content1);
});
layout.getChildren().clear();
layout.getChildren().add(content2);
}
If you don't want to add content dynamically, just setVisible() to true or false
Got stuck up in this too
Tried out most of the answers, wasn't what I wanted so I just used the ideals given to do this:
public class Main extends Application {
public static Stage homeStage;
#Override
public void start(Stage primaryStage) throws Exception{
homeStage = primaryStage;
Parent root = FXMLLoader.load(getClass().getResource("mainView.fxml"));
root.getStylesheets().add(getClass().getResource("stylesheet/custom.css").toExternalForm());
homeStage.setTitle("Classification of Living Organisms");
homeStage.setScene(new Scene(root, 600, 500));
homeStage.show();
}
public static void main(String[] args) {
launch(args);
}
}
this is my main class. Main.java with the landing window/page mainView.fxml.
Used a little of #Tomasz idea, although confused me a lil before I did this in my mainController.java class:
public void gotoSubMenu(Event event) {
Parent window1;
try {
window1 = FXMLLoader.load(getClass().getResource("src/displayView.fxml"));
Stage window1Stage;
Scene window1Scene = new Scene(window1, 600, 500);
window1Stage = Main.homeStage;
window1Stage.setScene(window1Scene);
} catch (IOException e) {
e.printStackTrace();
}
}
created a new Parent window called 'window1' that loaded the second fxml file called 'displayView.fxml' in the src directory.
created an object of the main view stage and set the scene to the newly created scene whose root is window1.
Hope this helps the ones coming into #JavaFX now.
If you're looking for a way to make the button call the new fxml file, this worked for me.
#FXML
private void mainBClicked(ActionEvent event) throws IOException {
Stage stage;
Parent root;
stage=(Stage) ((Button)(event.getSource())).getScene().getWindow();
root = FXMLLoader.load(getClass().getResource("MainMenu.fxml"));
Scene scene = new Scene(root);
stage.setScene(scene);
stage.show();
}
Keeping the same scene container but changing the view inside the scene container...
Say the scene container you want to pass a new view and controller into is a GridPane layout named sceneContainer.
Establish a FXMLLoader object of the new view.
FXMLLoader fxmlLoader = new FXMLLoader(getClass().getResource("Notifications.fxml"));
Create a matching container and loading the contents of the new view into it.
GridPane yourNewView = fxmlLoader.load();
set the new view to the sceneContainer. (setAll clears all children first)
sceneContainer.getChildren().setAll(yourNewView);
Get the controller object for the new view and call your method that starts the class logic
Notifications notifications = fxmlLoader.getController();
notifications.passUserName(userName);
A full example would look like this :
#FXML
public void setNotificationsViewToScene() {
try {
FXMLLoader fxmlLoader = new FXMLLoader(getClass().getResource("Notifications.fxml"));
GridPane yourNewView = fxmlLoader.load();
sceneContainer.getChildren().setAll(yourNewView);
Notifications notifications = fxmlLoader.getController();
notifications.passUserName(userName);
} catch (IOException e) {
e.printStackTrace();
}
}
Wow, >8 years old with lots of complicated answers and no mention of the >10 year old solution.
There is a dedicated fx:include element for nesting FXML files. It's not in the SceneBuilder library, so you need to write it manually. SceneBuilder can load and display nested FXML just fine though.
<AnchorPane fx:id="content">
<children>
<fx:include fx:id="nestedVista" source="vista2.fxml" />
</children>
</AnchorPane>
You can reference the nested Pane and controller using the fx:id and fx:id+"Controller"
#FXML
Pane nestedVista;
#FXML
VistaController nestedVistaController;
Documentation link: https://docs.oracle.com/javafx/2/api/javafx/fxml/doc-files/introduction_to_fxml.html#nested_controllers
I have 2 fxml files:
Layout (header, menubars and content)
Anchorpane (it's supposed to be placed inside the content from the other fxml file)
I would like to know how can I load the second file inside the content space from the "Master" scene. And is that a good thing to do working in javaFX or is it better to load a new scene?
I'm trying to do something like this, but it doesn't work:
#FXML
private AnchorPane content;
#FXML
private void handleButtonAction(ActionEvent event) {
content = (AnchorPane) FXMLLoader.load("vista2.fxml");
}
Thanks for the help.
Why your code does not work
The loader creates a new AnchorPane, but you never add the new pane to a parent in the scene graph.
Quick Fix
Instead of:
content = (AnchorPane) FXMLLoader.load("vista2.fxml");
Write:
content.getChildren().setAll(FXMLLoader.load("vista2.fxml"));
Replacing the content children with your new vista. The content itself remains in the scene graph, so when you set it's children, you are also attaching them to the scene graph at the same time.
You might need to play around with layout (e.g. work with auto resizing layouts like StackPanes rather than AnchorPanes) to get the exact behaviour you want.
Rather than just adopting the quick fix, I would advise reviewing the simple framework linked below as that might provide you with a more general purpose mechanism to get the behaviour you want.
Reference FXML Navigation Framework
I created a small framework for swapping fxml controlled content panes in and out of a portion of the main scene.
The mechanism of the framework is the same as suggested in kithril's answer.
A main pane for the outer fxml acts as a holder for child panes.
The main controller for the outer fxml supplies a public method that can be used to swap the child panes.
A convenience navigator class is statically initialized with the main controller for the outer layout.
The navigator provides a public static method to load a new child pane into the main container (by invoking a method on the main controller).
Child panes are generated in the navigator by their respective fxml loaders.
Why a Framework
The framework seems like overkill for answering your question, and perhaps it is. However, I have found that the two most asked topic related to FXML are:
Navigation between panes generated by FXML (this question).
How to pass data between FXML controllers.
So I felt that a small demo framework was warranted for this case.
Sample Framework Output
The first screen shows the application layout displaying the first vista. The contents are a header which is defined in the main application layout and an aliceblue colored interchangable child content pane.
In the next screen, the user has navigated to the second vista, which retains the constant header from the main layout and replaces the original child pane with a new coral colored child content pane. The new child has been loaded from a new fxml file.
Looking for Something More Substantial?
A lightweight framework which is more extensive and better supported than the sample framework from this question is afterburner.fx.
Looking for Something Even Simpler?
Just swap out the scene root: Changing Scenes in JavaFX.
Other Options?
Animated Transitions and others: Switch between panes in JavaFX
Im not sure about how effective this is, but seems to be just fine and what's more, much simpler to methods above.
https://www.youtube.com/watch?v=LDVztNtJWOo
As far as I understood what is happening here is this(its really similiar to what is happening in Start() method in application class) :
private void buttonGoToWindow3Action(ActionEvent event) throws IOException{
Parent window3; //we need to load the layout that we want to swap
window3 = (StackPane)FXMLLoader.load(getClass().getResource("/ScenePackage/FXMLWindow3"));
Scene newScene; //then we create a new scene with our new layout
newScene = new Scene(window3);
Stage mainWindow; //Here is the magic. We get the reference to main Stage.
mainWindow = (Stage) ((Node)event.getSource()).getScene().getWindow();
mainWindow.setScene(newScene); //here we simply set the new scene
}
However Im not a java expert and quite new to programing so it would be good if someone experienced would evaluate it.
EDIT:
Ive found even simpler method;
Go to MainApplication class and make static Stage parentWindow.
public static Stage parentWindow;
#Override
public void start(Stage stage) throws Exception {
parentWindow = stage;
Parent root = FXMLLoader.load(getClass().getResource("/ScenePackage/FXMLMainScene.fxml"));
Scene scene = new Scene(root);
stage.setScene(scene);
stage.show();
}
Now you get acces to your main Stage so anywhere in a program you can do something like that to change the scene:
Parent window1;
window1 = FXMLLoader.load(getClass().getResource("/ScenePackage/FXMLWindow1.fxml"));
//Scene newSceneWindow1 = new Scene(window1);
Stage mainStage;
//mainStage = (Stage) ((Node)event.getSource()).getScene().getWindow();
mainStage = MainApplication.parentWindow;
mainStage.getScene().setRoot(newSceneWindow1); //we dont need to change whole sceene, only set new root.
Others may have a better solution, but my solution has been to have a simple container like VBox in the outer fxml, then load the new content and add it as a child of the container. If you're only loading one or two forms, this might be the way go to go. However, for a more complete framework, I found this blog post helpful: https://blogs.oracle.com/acaicedo/entry/managing_multiple_screens_in_javafx1 She has source code for her framework which includes fancy transitions. Although it's meant to manage top level scenes, I found it easy to adapt for managing inner content regions too.
My example of the mask.
Using:
Main.getNavigation().load(View2.URL_FXML).Show();
Main.getNavigation().GoBack();
In this case, I recommend you to use custom component instead. First create a custom component for your content:
class Content2 extends AnchorPane {
Content() {
FXMLLoader loader = new FXMLLoader(getClass().getResource("vista2.fxml");
loader.setRoot(this);
loader.setController(this);
loader.load();
}
}
Replace the AnchorPane markup in the root of your vista2.fxml file with fx:root:
<fx:root type="javafx.scene.layout.AnchorPane" xmlns:fx="http://javafx.com/fxml">
...
</fx:root>
Then, you can do this simply by using custom event binding and arrow function. Add event handler property to your Content class:
private final ObjectProperty<EventHandler<ActionEvent>> propertyOnPreviousButtonClick = new SimpleObjectProperty<EventHandler<ActionEvent>>();
#FXML
private void onPreviousButtonClick(ActionEvent event) {
propertyOnPreviousButtonClick.get().handle(event)
}
public void setOnPreviousButtonClick(EventHandler<ActionEvent> handler) {
propertyOnPreviousButtonClick.set(handler);
}
Finally, bind your custom event handler in your java code or fxml:
#FXML
onNextButtonClick() {
Content2 content2 = new Content2();
content2.setOnPreviousButtonClick((event) -> {
Content1 content1 = new Content1();
layout.getChildren().clear();
layout.getChildren().add(content1);
});
layout.getChildren().clear();
layout.getChildren().add(content2);
}
If you don't want to add content dynamically, just setVisible() to true or false
Got stuck up in this too
Tried out most of the answers, wasn't what I wanted so I just used the ideals given to do this:
public class Main extends Application {
public static Stage homeStage;
#Override
public void start(Stage primaryStage) throws Exception{
homeStage = primaryStage;
Parent root = FXMLLoader.load(getClass().getResource("mainView.fxml"));
root.getStylesheets().add(getClass().getResource("stylesheet/custom.css").toExternalForm());
homeStage.setTitle("Classification of Living Organisms");
homeStage.setScene(new Scene(root, 600, 500));
homeStage.show();
}
public static void main(String[] args) {
launch(args);
}
}
this is my main class. Main.java with the landing window/page mainView.fxml.
Used a little of #Tomasz idea, although confused me a lil before I did this in my mainController.java class:
public void gotoSubMenu(Event event) {
Parent window1;
try {
window1 = FXMLLoader.load(getClass().getResource("src/displayView.fxml"));
Stage window1Stage;
Scene window1Scene = new Scene(window1, 600, 500);
window1Stage = Main.homeStage;
window1Stage.setScene(window1Scene);
} catch (IOException e) {
e.printStackTrace();
}
}
created a new Parent window called 'window1' that loaded the second fxml file called 'displayView.fxml' in the src directory.
created an object of the main view stage and set the scene to the newly created scene whose root is window1.
Hope this helps the ones coming into #JavaFX now.
If you're looking for a way to make the button call the new fxml file, this worked for me.
#FXML
private void mainBClicked(ActionEvent event) throws IOException {
Stage stage;
Parent root;
stage=(Stage) ((Button)(event.getSource())).getScene().getWindow();
root = FXMLLoader.load(getClass().getResource("MainMenu.fxml"));
Scene scene = new Scene(root);
stage.setScene(scene);
stage.show();
}
Keeping the same scene container but changing the view inside the scene container...
Say the scene container you want to pass a new view and controller into is a GridPane layout named sceneContainer.
Establish a FXMLLoader object of the new view.
FXMLLoader fxmlLoader = new FXMLLoader(getClass().getResource("Notifications.fxml"));
Create a matching container and loading the contents of the new view into it.
GridPane yourNewView = fxmlLoader.load();
set the new view to the sceneContainer. (setAll clears all children first)
sceneContainer.getChildren().setAll(yourNewView);
Get the controller object for the new view and call your method that starts the class logic
Notifications notifications = fxmlLoader.getController();
notifications.passUserName(userName);
A full example would look like this :
#FXML
public void setNotificationsViewToScene() {
try {
FXMLLoader fxmlLoader = new FXMLLoader(getClass().getResource("Notifications.fxml"));
GridPane yourNewView = fxmlLoader.load();
sceneContainer.getChildren().setAll(yourNewView);
Notifications notifications = fxmlLoader.getController();
notifications.passUserName(userName);
} catch (IOException e) {
e.printStackTrace();
}
}
Wow, >8 years old with lots of complicated answers and no mention of the >10 year old solution.
There is a dedicated fx:include element for nesting FXML files. It's not in the SceneBuilder library, so you need to write it manually. SceneBuilder can load and display nested FXML just fine though.
<AnchorPane fx:id="content">
<children>
<fx:include fx:id="nestedVista" source="vista2.fxml" />
</children>
</AnchorPane>
You can reference the nested Pane and controller using the fx:id and fx:id+"Controller"
#FXML
Pane nestedVista;
#FXML
VistaController nestedVistaController;
Documentation link: https://docs.oracle.com/javafx/2/api/javafx/fxml/doc-files/introduction_to_fxml.html#nested_controllers