JavaFX FXML文本组件控制器未更新

Question

<GridPane   fx:id="mainPane" 
        styleClass="mainFxmlClass" 
        xmlns:fx="http://javafx.com/fxml/1" 
        fx:controller="org.lgdor.dieSim.MainWindowController" 
        xmlns="http://javafx.com/javafx/8.0_40"
        prefHeight="800.0" 
        prefWidth="800.0" 
        hgap="10" 
        vgap="10" >
<stylesheets>
    <URL value="@mainwindow.css"/>
</stylesheets>
<padding>
    <Insets top="25" right="25" bottom="10" left="25"/>
</padding>
<Text fx:id="welcomeText" text="Welcome to DieSim" 
      GridPane.columnIndex="0" 
      GridPane.rowIndex="0"
      GridPane.columnSpan="5"/>
<Label fx:id="spinnerText"
       text="Please input the number of dice you want to roll:"
       GridPane.columnIndex="0" 
       GridPane.rowIndex="1"
       GridPane.columnSpan="2"/>
<Spinner fx:id="spinner" editable="true" 
         GridPane.columnIndex="3" 
         GridPane.rowIndex="1" />
<HBox fx:id="buttonBox"
      spacing="10" 
      alignment="center" 
      GridPane.columnIndex="5" 
      GridPane.rowIndex="1">
    <Button text="Roll Dice" onAction="#createDice"/>

</HBox>
<Label fx:id="dieNumberText" text="The number of dice is: "
      GridPane.columnIndex="0" 
      GridPane.rowIndex="2"
      GridPane.columnSpan="2"/>
<Text fx:id="dieNumber" GridPane.columnIndex="3" GridPane.rowIndex="2" />
<Label fx:id="dieSumText" text="The sum of the dice is: "
      GridPane.columnIndex="0" 
      GridPane.rowIndex="3"
      GridPane.columnSpan="2"/>
<Text fx:id="sumNumber" GridPane.columnIndex="3" GridPane.rowIndex="3" />
<VBox fx:id="rowBox"
      spacing="10" 
      alignment="center" 
      GridPane.columnIndex="0" 
      GridPane.rowIndex="4"
      GridPane.columnSpan="5" >
    <Text text="This is where the list of dice goes..."/>

</VBox>

public class MainWindowController implements Initializable {

@FXML
Label spinnerText;

@FXML
Spinner spinner;

@FXML
HBox buttonBox;

@FXML
Text dieNumber;

@FXML
Text sumNumber;

@FXML
int numberOfDice = 0;

@FXML
int sumOfDice = 0;

@FXML
VBox rowBox;

private List<Die> dieList = new ArrayList<>();
private List<GridPane> rowList = new ArrayList<>();

public void createDice() throws IOException{
    numberOfDice = (int)spinner.getValue();

    for (int i=0;i<numberOfDice;i++){
        Die die = new Die(i);
        die.roll(null);
        sumOfDice = sumOfDice + Integer.parseInt(die.getValue());
        dieList.add(die);
        rowBox.getChildren().add(die);
    }
    dieNumber.setText(String.valueOf(numberOfDice));
    sumNumber.setText(String.valueOf(sumOfDice));
    spinner.setVisible(false);
    spinnerText.setVisible(false);
    buttonBox.setVisible(false);
}

/**
 * Initializes the controller class.
 */
@Override
public void initialize(URL url, ResourceBundle rb) {
    spinner.setValueFactory(new SpinnerValueFactory.IntegerSpinnerValueFactory(1, 20));
    dieNumber.setText("0");
    sumNumber.setText(String.valueOf("0"));
    spinnerText.setVisible(true);
    spinner.setVisible(true);
    buttonBox.setVisible(true);

}    
}

<fx:root type="javafx.scene.layout.GridPane" 
      xmlns:fx="http://javafx.com/fxml/1"  
      xmlns="http://javafx.com/javafx/8.0_40" >
<HBox spacing="30" alignment="center" GridPane.columnIndex="0" GridPane.rowIndex="0"  >
    <Text fx:id="number" /><!--This is the problem component-->
    <Text fx:id="value"/>
    <Button fx:id="dieButton" text="Roll Dice" onAction="#roll"  />
</HBox>
</fx:root>

public class Die extends GridPane implements Initializable {

@FXML
private Text number;//This is the problem component ...
public String getNumber() {
    return numberTextProperty().get();
}
public void setNumber(String number) {
    numberTextProperty().set(number);
}
public StringProperty numberTextProperty() {
    return number.textProperty();
}

@FXML
private Text value;
public String getValue() {
    return valueTextProperty().get();
}
public void setValue(String value) {
    valueTextProperty().set(value);
}
public StringProperty valueTextProperty() {
    return value.textProperty();
}

public Die(int i) throws IOException{
    FXMLLoader fxmlLoader = new FXMLLoader(getClass().getResource("DieGUI.fxml"));
    fxmlLoader.setRoot(this);
    fxmlLoader.setController(this);
    this.number = new Text(String.valueOf(i));
    this.setNumber(String.valueOf(1));
    this.value = new Text();
    this.setValue(String.valueOf(1));
    fxmlLoader.load();  
}

@FXML
public void roll(ActionEvent event){
    this.setValue(String.valueOf((int)(6*Math.random()+1)));
}

@Override
public void initialize(URL location, ResourceBundle resources) {
}
}

Answer 1

问题是您创建了一个新的text实例，而不是配置FXML中已经创建的实例：

this.number = new Text(String.valueOf(i));

@fxml注释的全部用途是指示字段是由FXMLLoader初始化的，因此初始化注释@fxml的字段总是错误的。

这里请注意，这些字段是在调用load()期间由FXMLLoader初始化的，因此在以任何方式配置它们之前都需要调用load()。

public Die(int i) throws IOException{
    FXMLLoader fxmlLoader = new FXMLLoader(getClass().getResource("DieGUI.fxml"));
    fxmlLoader.setRoot(this);
    fxmlLoader.setController(this);
    fxmlLoader.load();  

    // these don't seem to do anything useful?
    // this.setNumber(String.valueOf(1));
    // this.setValue(String.valueOf(1));

    this.number.setText(String.valueOf(i));
    this.value.setText(String.valueOf(i));
}