Java:如何从主类调用GUI类(没有Swing/JFrame)

Question

这个问题已经有答案了:

Java: How do I start a standalone application from the current one when both are in the same package? (3 个回答)

已关闭 6 年前。

我是 Java 新手。我想构建一个餐厅应用程序。在主类中，我想做的就是从其他类调用 GUI(以及后来的方法，但这不是问题)。这是主类的代码(注释是德语):

package Restaurant;

import javafx.application.Application;
import javafx.event.ActionEvent;
import javafx.event.EventHandler;
import javafx.geometry.Insets;
import javafx.scene.Scene;
import javafx.scene.control.Button;
import javafx.scene.layout.GridPane;
import javafx.stage.Stage;

public class Tisch_Auswahl extends Application {
  // Zutaten für die erste (primary) stage / Auswahlseite
  GridPane pane0 = new GridPane();
  Scene scene0 = new Scene(pane0);

  Button button1 = new Button("Tisch 1");
  Button button2 = new Button("Tisch 2");
  Button button3 = new Button("Tisch 3");



  EventHandler<ActionEvent> Tisch1 = new EventHandler<ActionEvent>() {
@Override
public void handle(ActionEvent event) {
  Tisch1.show(); // Zweite Bühne wird angezeigt
  // In diesen EventHandler muss eigentlich Befehl für Abruf der Klasse?
}
  };

  EventHandler<ActionEvent> Tisch2 = new EventHandler<ActionEvent>() {
    @Override
    public void handle(ActionEvent event) {
      Tisch2.show(); // Zweite Bühne wird angezeigt
      // In diesen EventHandler muss eigentlich Befehl für Abruf der Klasse?
    }
      };

  EventHandler<ActionEvent> Tisch3 = new EventHandler<ActionEvent>() {
        @Override
        public void handle(ActionEvent event) {
          Tisch3.show(); // Zweite Bühne wird angezeigt
          // In diesen EventHandler muss eigentlich Befehl für Abruf der Klasse?
        }
      };



  public void start(Stage primaryStage) throws Exception {
// Erste stage vorbereiten
primaryStage.setScene(scene0);
primaryStage.setTitle("Bestellsystem");

pane0.setPadding(new Insets(10));
pane0.setHgap(20);
pane0.setVgap(20);

pane0.addRow(0, button1, button2, button3);




button1.setOnAction(Tisch1);
button2.setOnAction(Tisch2);
button3.setOnAction(Tisch3);

primaryStage.show();

  }

  public static void main(String[] args) {
launch();
  }
}

在主类中，有“tisch 1 - 3”(表示表 1 - 3)的三个 EventHandler。我为每个表创建了一个类，每个类都是相同的。这是表 1 的类的代码:

package Restaurant;

import javafx.application.Application;
import javafx.collections.FXCollections;
import javafx.collections.ObservableList;
import javafx.event.ActionEvent;
import javafx.event.EventHandler;
import javafx.geometry.Insets;
import javafx.scene.Scene;
import javafx.scene.control.Button;
import javafx.scene.control.ComboBox;
import javafx.scene.control.Label;
import javafx.scene.layout.GridPane;
import javafx.stage.Stage;


public class Tisch1 extends Application {
  GridPane pane1 = new GridPane(); 
  Scene szene_1 = new Scene(pane1, 600, 650);

  Label l0 = new Label("Menü");
Label l1 = new Label("Vorspeise");
Label l2 = new Label("Hauptspeise");
Label l3 = new Label("Dessert");
Label l4 = new Label("Getränke");

Label l5 = new Label("Suppe");
Label l6 = new Label("Bruschetta");
Label l7 = new Label("Dip");

Label l8 = new Label("Pide");
Label l9 = new Label("Pizza");
Label l10 = new Label("Pasta");

Label l11 = new Label("Rote Grütze");
Label l12 = new Label("Tiramisu");
Label l13 = new Label("Eis");

Label l14 = new Label("Bier");
Label l15 = new Label("Wasser");
Label l16 = new Label("Wein");

ObservableList<String> Menge1 = FXCollections.observableArrayList("0", "1", "2", "3", "4", "5", "6", "7", "8", "9",
        "10");
ComboBox<String> menge1 = new ComboBox<>(Menge1);

ObservableList<String> Menge2 = FXCollections.observableArrayList("0", "1", "2", "3", "4", "5", "6", "7", "8", "9",
        "10");
ComboBox<String> menge2 = new ComboBox<>(Menge2);

ObservableList<String> Menge3 = FXCollections.observableArrayList("0", "1", "2", "3", "4", "5", "6", "7", "8", "9",
        "10");
ComboBox<String> menge3 = new ComboBox<>(Menge3);

ObservableList<String> Menge4 = FXCollections.observableArrayList("0", "1", "2", "3", "4", "5", "6", "7", "8", "9",
        "10");
ComboBox<String> menge4 = new ComboBox<>(Menge4);

ObservableList<String> Menge5 = FXCollections.observableArrayList("0", "1", "2", "3", "4", "5", "6", "7", "8", "9",
        "10");
ComboBox<String> menge5 = new ComboBox<>(Menge5);

ObservableList<String> Menge6 = FXCollections.observableArrayList("0", "1", "2", "3", "4", "5", "6", "7", "8", "9",
        "10");
ComboBox<String> menge6 = new ComboBox<>(Menge6);

ObservableList<String> Menge7 = FXCollections.observableArrayList("0", "1", "2", "3", "4", "5", "6", "7", "8", "9",
        "10");
ComboBox<String> menge7 = new ComboBox<>(Menge7);

ObservableList<String> Menge8 = FXCollections.observableArrayList("0", "1", "2", "3", "4", "5", "6", "7", "8", "9",
        "10");
ComboBox<String> menge8 = new ComboBox<>(Menge8);

ObservableList<String> Menge9 = FXCollections.observableArrayList("0", "1", "2", "3", "4", "5", "6", "7", "8", "9",
        "10");
ComboBox<String> menge9 = new ComboBox<>(Menge9);

ObservableList<String> Menge10 = FXCollections.observableArrayList("0", "1", "2", "3", "4", "5", "6", "7", "8", "9",
        "10");
ComboBox<String> menge10 = new ComboBox<>(Menge10);

ObservableList<String> Menge11 = FXCollections.observableArrayList("0", "1", "2", "3", "4", "5", "6", "7", "8", "9",
        "10");
ComboBox<String> menge11 = new ComboBox<>(Menge11);

ObservableList<String> Menge12 = FXCollections.observableArrayList("0", "1", "2", "3", "4", "5", "6", "7", "8", "9",
        "10");
ComboBox<String> menge12 = new ComboBox<>(Menge12);

Button b1 = new Button("Nächste Bestellung");
Button b2 = new Button("Rechnung drucken");


  public void start (Stage Tisch1) {
  pane1.add(l1, 0, 1);
  pane1.add(l2, 0, 5);
  pane1.add(l3, 0, 9);
  pane1.add(l4, 0, 13);

  pane1.add(l5, 1, 1);
  pane1.add(l6, 1, 2);
  pane1.add(l7, 1, 3);

  pane1.add(l8, 1, 5);
    pane1.add(l9, 1, 6);
    pane1.add(l10, 1, 7);

    pane1.add(l11, 1, 9);
    pane1.add(l12, 1, 10);
    pane1.add(l13, 1, 11);

    pane1.add(l14, 1, 13);
    pane1.add(l15, 1, 14);
    pane1.add(l16, 1, 15);

    pane1.add(menge1, 2, 1);
    pane1.add(menge2, 2, 2);
    pane1.add(menge3, 2, 3);
    pane1.add(menge4, 2, 5);
    pane1.add(menge5, 2, 6);
    pane1.add(menge6, 2, 7);
    pane1.add(menge7, 2, 9);
    pane1.add(menge8, 2, 10);
    pane1.add(menge9, 2, 11);
    pane1.add(menge10, 2, 13);
    pane1.add(menge11, 2, 14);
    pane1.add(menge12, 2, 15);

    pane1.add(b1, 2, 17);
    pane1.add(b2, 3, 17);

    menge1.getSelectionModel().select("0");
    menge2.getSelectionModel().select("0");
    menge3.getSelectionModel().select("0");
    menge4.getSelectionModel().select("0");
    menge5.getSelectionModel().select("0");
    menge6.getSelectionModel().select("0");
    menge7.getSelectionModel().select("0");
    menge8.getSelectionModel().select("0");
    menge9.getSelectionModel().select("0");
    menge10.getSelectionModel().select("0");
    menge11.getSelectionModel().select("0");
    menge12.getSelectionModel().select("0");

    pane1.setPadding(new Insets(10));
    pane1.setHgap(12);
    pane1.setVgap(12);

    EventHandler<ActionEvent> Nächste_Bestellung = new EventHandler<ActionEvent>() {
          public void handle(ActionEvent event) {
              Tisch1.close();

          }
        };

        EventHandler<ActionEvent> Rechnung_erstellen = new EventHandler<ActionEvent>() {
              public void handle(ActionEvent event) {

              }
            };

        b1.setOnAction(Nächste_Bestellung);
        b2.setOnAction(Rechnung_erstellen);

Tisch1.setScene(szene_1);
Tisch1.setTitle("Tisch 1");
Tisch1.show();
  }

  public static void main(String[] args) {
launch(args);
  }
}

那么我如何在我的主类中调用表 1 的 GUI 呢？我使用 Swing 找到了答案，但我不想将其混淆。请帮助我:)

Answer 1

代码中GUI的典型操作有:

1. 创建并显示应用程序窗口(根容器)
2. 编写一个 GUI 组件并添加到某个容器
3. 订阅/取消订阅 GUI 事件
4. 更改 GUI 组件的状态

第一个通常在主应用程序类中完成，可能是包含 main 方法的类。其余的最好遵循 MVC 模式，其中 V 代表 View(JavaFX 或 Swing 类的实例，负责渲染和接收用户输入)，M 是数据模型(例如餐厅的菜单项列表)，C 是 Controller 类，负责组成 View 、订阅和处理 View 事件以及更新模型。所以你的代码可能看起来像这样(伪代码，因为我不熟悉 javafx API):

interface Controller {
     Node getView();
}

class TableController {
   ...
}

class MainScreenController implements Controller, ReservationListener {
    private Restaurant model;
    private StackPane view;
    private List<TableController> children;
    public MainScreenController(Restaurant restaurant) {
        view = new StackPane();
        // compose this view from table views for each table
        for (Table table : model.getTables()) {
             TableController controller = new TableController(table);
             view.getChildren().add(controller.getView());
             // when Reserve button is clicked in TableController, we want
             // to receive reservation events here and update restaurant
             // status
             controller.addReservationListener(this);
        }
        // add more components here and subscriptions on events
    }
    // receives reservation events from tables
    public void tableReserved(Table table) { 
        ...
    }
}

class MyApplication extends Application {
   // a model that could be loaded from file or database
   private Restaurant restaurant = new Restaurant(); 
   // a controller for the main view
   private RestaurantController controller = new RestaurantController(restaurant);
   public void start(Stage stage) {
      // here you just initialize the stage with the view
      // from your main controller
      stage.setScene(new Scene(main.getView(), 400, 300));
      // you only need to show the root, the rest is already part of it
      stage.show(); 
   } 
}

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