java - 如何从 javafx 中的切换按钮获取文本

Question

我是 JavaFX 的新手。我正在从事电影预订项目。我试图在循环后从切换按钮中检索文本，但我没有看到 getText() 方法。有没有办法从切换按钮获取文本。

这是我的代码:

package theatre;

import javafx.event.ActionEvent;
import javafx.event.EventHandler;
import javafx.fxml.FXML;
import javafx.fxml.Initializable;
import javafx.scene.control.ToggleButton;
import javafx.scene.layout.GridPane;

import java.net.URL;
import java.util.ResourceBundle;

public class TheatreController implements Initializable {

@FXML
private GridPane middleGridPane;

private final int MAX_ROW = 5;
private final int MAX_COL = 5;

@Override
public void initialize(URL url, ResourceBundle resourceBundle) {
    int countRow = 1;
    ToggleButton[][] seats = new ToggleButton[MAX_ROW][MAX_COL];

    char lastRow = 'A' + (MAX_ROW - 1);

    for(char row = 'A'; row < lastRow; row++){
        for (int col = 1; col < MAX_COL; col++){
            seats[countRow][col] = new ToggleButton(String.format(row + "%02d", col));
            seats[countRow][col].setPrefWidth(50);
            middleGridPane.add(seats[countRow][col], countRow, col);
            seats[countRow][col].setOnAction(new EventHandler<ActionEvent>() {
                @Override
                public void handle(ActionEvent event) {
                    // Can't get text from here
                    event.getEventType().getName();
                }
            });

        }
        countRow++;
    }
}

@FXML
public void bookSeat(){

}
}

Answer 1

您在 EventHandler 的 handle() 中使用的任何变量都必须是 final 或 effectively finel .

这是您问题的解决方案:

import javafx.event.ActionEvent;
import javafx.event.EventHandler;
import javafx.fxml.FXML;
import javafx.fxml.Initializable;
import javafx.scene.control.ToggleButton;
import javafx.scene.layout.GridPane;
import java.net.URL;
import java.util.ResourceBundle;

public class TheatreController implements Initializable {
    
    @FXML
    private GridPane middleGridPane;
    
    private final int MAX_ROW = 5;
    private final int MAX_COL = 5;
    
    @Override
    public void initialize(URL url, ResourceBundle resourceBundle) {
        int countRow = 1;
        ToggleButton[][] seats = new ToggleButton[MAX_ROW][MAX_COL];
        
        char lastRow = 'A' + (MAX_ROW - 1);
        
        for(char row = 'A'; row < lastRow; row++){
            for (int col = 1; col < MAX_COL; col++){
                seats[countRow][col] = new ToggleButton(String.format(row + "%02d", col));
                seats[countRow][col].setPrefWidth(50);
                middleGridPane.add(seats[countRow][col], countRow, col);
                
                //effectively final variable to use in handle method of EventHandler
                int finalCountRow = countRow;
                int finalCol      = col;
                
                seats[countRow][col].setOnAction(new EventHandler<ActionEvent>() {
                    @Override
                    public void handle(ActionEvent event) {
    
                        //now you can get text from seats[finalCountRow][finalCol]
                        System.out.println(seats[finalCountRow][finalCol].getText());
                        event.getEventType().getName();
                    }
                });
            }
            countRow++;
        }
    }
    
    @FXML
    public void bookSeat(){
    
    }
}