src/main/java/fr/myny/gui/Gui.java

@@ -0,0 +1,33 @@
+package fr.myny.gui;
+
+import javafx.application.Application;
+import javafx.fxml.FXMLLoader;
+import javafx.scene.Parent;
+import javafx.scene.Scene;
+import javafx.stage.Stage;
+import java.io.IOException;
+
+public class Gui extends Application {
+
+    private static Scene scene;
+
+    @Override
+    public void start(Stage stage) throws IOException {
+        scene = new Scene(loadFXML("primary"));
+        stage.setScene(scene);
+        stage.show();
+    }
+
+    static void setRoot(String fxml) throws IOException {
+        scene.setRoot(loadFXML(fxml));
+    }
+
+    private static Parent loadFXML(String fxml) throws IOException {
+        FXMLLoader fxmlLoader = new FXMLLoader(Gui.class.getResource(fxml + ".fxml"));
+        return fxmlLoader.load();
+    }
+
+    public static void main(String[] args) {
+        launch();
+    }
+}

src/main/java/fr/myny/gui/PrimaryController.java

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+package fr.myny.gui;
+
+import javafx.fxml.FXML;
+
+import java.io.IOException;
+
+public class PrimaryController {
+
+    @FXML
+    private void switchToSecondary() throws IOException {
+        Gui.setRoot("secondary");
+    }
+}

src/main/java/fr/myny/gui/SecondaryController.java

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+package fr.myny.gui;
+
+import javafx.fxml.FXML;
+
+import java.io.IOException;
+
+public class SecondaryController {
+
+    @FXML
+    private void switchToPrimary() throws IOException {
+        Gui.setRoot("primary");
+    }
+}

src/main/java/module-info.java

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+module fr.myny.gui {
+    requires javafx.controls;
+    requires javafx.fxml;
+
+    opens fr.myny.gui to javafx.fxml;
+    exports fr.myny.gui;
+}

src/main/resources/fr/myny/gui/primary.fxml

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+<?xml version="1.0" encoding="UTF-8"?>
+
+<?import javafx.geometry.*?>
+<?import javafx.scene.control.*?>
+<?import javafx.scene.layout.*?>
+
+<VBox alignment="CENTER" prefHeight="241.0" prefWidth="397.0" spacing="20.0" xmlns="http://javafx.com/javafx/11.0.1" xmlns:fx="http://javafx.com/fxml/1" fx:controller="fr.myny.gui.PrimaryController">
+   <Label prefHeight="167.0" prefWidth="69.0" text="Primary View" />
+   <Button onAction="#switchToSecondary" prefHeight="109.0" prefWidth="152.0" text="Switch to Secondary View" />
+   <padding>
+      <Insets bottom="20.0" left="20.0" right="20.0" top="20.0" />
+   </padding>
+</VBox>

src/main/resources/fr/myny/gui/secondary.fxml

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+<?xml version="1.0" encoding="UTF-8"?>
+
+<?import javafx.scene.layout.VBox?>
+<?import javafx.scene.control.Label?>
+<?import javafx.scene.control.Button?>
+<?import javafx.geometry.Insets?>
+
+<VBox alignment="CENTER" spacing="20.0" xmlns="http://javafx.com/javafx/8.0.171" xmlns:fx="http://javafx.com/fxml/1" fx:controller="fr.myny.gui.SecondaryController">
+    <Label text="Secondary View" />
+    <Button text="Switch to Primary View" onAction="#switchToPrimary" />
+    <padding>
+        <Insets bottom="20.0" left="20.0" right="20.0" top="20.0" />
+    </padding>
+</VBox>