Question

当我试图在start()方法（或更早）中更改或设置标签文字时，它似乎无法正常工作。其他事情也是如此，例如。为按钮设置onAction - 在start()中设置时不起作用。

如果我稍后在按钮激活的nextTurn()方法中设置这些内容，则会设置它们。在添加FXML之前设置标签和onAction。

我怀疑这些值可能会重置为它们在FXML中的含义。如果FXML中没有值，则标签为空。

如果是这种情况（FXML基值覆盖start()方法中设置的值），我应该在哪里设置标签和其他东西的初始值？假设初始值不能直接在FXML中输入，因为它们需要在显示屏幕之前计算。

代码下面（因为我尝试了各种选项，有点凌乱）：

核心课程：

public class TheCitadel extends Application {

    GameState gameState = GameInitializer.initializeGame(new GameState());
    PlayerCamp playerCamp = (PlayerCamp) gameState.getCamps().get(0);

    //Labels
    @FXML
    Label monthLabel = new Label();
    @FXML
    Label populationLabel = new Label();
    @FXML
    Label foodLabel = new Label();
    @FXML
    Label tradeGoodsLabel = new Label();
    @FXML
    Label craftsmenLabel = new Label();

    //Buttons
    @FXML
    Button nextTurnButton = new Button("Next turn");
    @FXML
    Button addCreaftsmenButton = new Button("Add Craftsmen");
    @FXML
    Button removeCreaftsmenButton = new Button("Remove Craftsmen");


    @Override
    public void start(Stage primaryStage) throws Exception {



        //stage and layout
        Stage mainWindow = primaryStage;
        mainWindow.setTitle("The Citadel");
        //GridPane layout = new GridPane();
        FXMLLoader loader = new FXMLLoader();
        loader.setLocation(getClass().getResource("/view/MainScreen.fxml"));
        Parent layout = loader.load();
        Scene mainScene = new Scene(layout);

        mainWindow.setScene(mainScene);
        mainWindow.show();

        monthLabel = new Label("Month: " + gameState.getTime().getCurrentMonth().toString());
        populationLabel = new Label("Population: " + String.valueOf(playerCamp.getPopulation()));
        populationLabel.setText ("Population: " + String.valueOf(playerCamp.getPopulation()));
        foodLabel = new Label("Food: " + String.valueOf(playerCamp.getFood()));
        tradeGoodsLabel = new Label("Trade goods: " + String.valueOf(playerCamp.getTradeGoods()));
        craftsmenLabel = new Label("Craftsmen: " + String.valueOf(playerCamp.getPopulationAsCraftsmen()));

        //buttons
        nextTurnButton.setOnAction(e -> {
                    proceedGameTime();
                    monthLabel.setText(gameState.getTime().getCurrentMonth().toString());
                    populationLabel.setText("Population: " + String.valueOf(playerCamp.getPopulation()));
                    foodLabel.setText("Food: " + String.valueOf(playerCamp.getFood()));
                    tradeGoodsLabel.setText("Trade goods: " + String.valueOf(playerCamp.getTradeGoods()));
                    craftsmenLabel.setText("Craftsmen: " + String.valueOf(playerCamp.getPopulationAsCraftsmen()));
                }
        );



        addCreaftsmenButton.setOnAction(e -> {
            if (playerCamp.getPopulation() >= 1) {
                playerCamp.setPopulation(playerCamp.getPopulation() - 1);
                populationLabel.setText("Population: " + String.valueOf(playerCamp.getPopulation()));
                playerCamp.setPopulationAsCraftsmen(playerCamp.getPopulationAsCraftsmen() + 1);
                craftsmenLabel.setText("Craftsmen: " + String.valueOf(playerCamp.getPopulationAsCraftsmen()));
            }
        });

        removeCreaftsmenButton.setOnAction(e -> {
            if (playerCamp.getPopulationAsCraftsmen() >= 1) {
                playerCamp.setPopulation(playerCamp.getPopulation() + 1);
                populationLabel.setText("Population: " + String.valueOf(playerCamp.getPopulation()));
                playerCamp.setPopulationAsCraftsmen(playerCamp.getPopulationAsCraftsmen() - 1);
                craftsmenLabel.setText("Craftsmen: " + String.valueOf(playerCamp.getPopulationAsCraftsmen()));
            }
        });

        //set layout

       // layout.getChildren().addAll(nextTurnButton, monthLabel, craftsmenLabel, populationLabel, foodLabel, tradeGoodsLabel, addCreaftsmenButton, removeCreaftsmenButton);
        /*
        layout.setPadding(new Insets(10, 10, 10, 10));
        layout.setVgap(5);
        layout.setHgap(5);
        GridPane.setConstraints(textArea, 1, 0);
        GridPane.setConstraints(nextTurnButton, 1, 2);
        GridPane.setConstraints(monthLabel, 0, 2);
        GridPane.setConstraints(populationLabel, 0, 0);
        GridPane.setConstraints(foodLabel, 0, 1);
        GridPane.setConstraints(tradeGoodsLabel, 1, 1);
        GridPane.setConstraints(addCreaftsmenButton, 2, 0);
        GridPane.setConstraints(removeCreaftsmenButton, 1, 0);
        GridPane.setConstraints(craftsmenLabel, 3, 0);
        */

    }


    public static void main(String[] args) {
        //TheCitadel citadel = new TheCitadel();
        launch(args);
    }

    @FXML
    public void nextTurn () {
        proceedGameTime();

       //setting labels and button text here works
        monthLabel.setText(gameState.getTime().getCurrentMonth().toString());
        populationLabel.setText("Population: " + 
        String.valueOf(playerCamp.getPopulation()));
        foodLabel.setText("Food: " + String.valueOf(playerCamp.getFood()));
        tradeGoodsLabel.setText("Trade goods: " + 
        String.valueOf(playerCamp.getTradeGoods()));
        craftsmenLabel.setText("Craftsmen: " + 
        String.valueOf(playerCamp.getPopulationAsCraftsmen()));
        addCreaftsmenButton.setText("THIS BUTTON SHOULD HAVE THIS TEXT AND WORK 
        EARLIER!!!");

       //setting onAction here works

        addCreaftsmenButton.setOnAction(e -> {
            if (playerCamp.getPopulation() >= 1) {
                playerCamp.setPopulation(playerCamp.getPopulation() - 1);
                populationLabel.setText("Population: " + String.valueOf(playerCamp.getPopulation()));
                playerCamp.setPopulationAsCraftsmen(playerCamp.getPopulationAsCraftsmen() + 1);
                craftsmenLabel.setText("Craftsmen: " + String.valueOf(playerCamp.getPopulationAsCraftsmen()));
            }
        });
    }


    public void proceedGameTime() {
        gameState.getTime().proceedGameTime(1);
    }

}

-

FXML：

<AnchorPane prefHeight="600.0" prefWidth="335.0" xmlns="http://javafx.com/javafx/8.0.141" xmlns:fx="http://javafx.com/fxml/1" fx:controller="controllers.TheCitadel">
   <children>
      <Button fx:id="nextTurnButton" onAction="#nextTurn" layoutY="551.0" mnemonicParsing="false" prefHeight="48.0" prefWidth="194.0" text="Next turn" AnchorPane.bottomAnchor="1.0" AnchorPane.leftAnchor="0.0" AnchorPane.rightAnchor="0.0" />
      <AnchorPane layoutY="200.0" prefHeight="232.0" prefWidth="335.0" AnchorPane.leftAnchor="0.0" AnchorPane.rightAnchor="0.0" />
      <TabPane layoutX="14.0" layoutY="-17.0" prefHeight="280.0" prefWidth="200.0" tabClosingPolicy="UNAVAILABLE" AnchorPane.bottomAnchor="400.0" AnchorPane.leftAnchor="0.0" AnchorPane.rightAnchor="0.0" AnchorPane.topAnchor="0.0">
        <tabs>
          <Tab text="Untitled Tab 1">
            <content>
              <AnchorPane minHeight="0.0" minWidth="0.0" prefHeight="280.0" prefWidth="200.0">
                     <children>
                        <Label  text="33333333" fx:id="populationLabel" layoutX="14.0" layoutY="9.0" />
                        <Label fx:id="tradeGoodsLabel" layoutX="14.0" layoutY="40.0" />
                        <Label fx:id="foodLabel" layoutX="172.0" layoutY="22.0" />
                         <Button fx:id="addCreaftsmenButton" layoutY="551.0" mnemonicParsing="false" prefHeight="48.0" prefWidth="194.0" text="addCreaftsmenButton" AnchorPane.bottomAnchor="1.0" AnchorPane.leftAnchor="0.0" AnchorPane.rightAnchor="0.0" />

                     </children>
              </AnchorPane>
            </content>
          </Tab>
          <Tab text="Untitled Tab 2">
            <content>
              <AnchorPane minHeight="0.0" minWidth="0.0" prefHeight="180.0" prefWidth="200.0" />
            </content>
          </Tab>
        </tabs>
      </TabPane>
   </children>
</AnchorPane>

Answer 1

您不能实例化使用@FXML注释的节点，它们将由JavaFX注入，并且您正在重新分配它们。摆脱所有new Label()等。此外，您不应将Application类用作控制器。将标签，按钮和事件处理程序移动到单独的类。然后，在你的fxml中，输入#onAction=yourEventHandlerMethod。 JavaFX支持

@FXML 
private void initialize()

控制器中的

方法，您可以在其中放置初始化逻辑。

使用FXML在start（）中使用时，setText（）不起作用

1 个答案: