无法更改标签和按钮的值

时间:2018-07-26 18:54:00

标签: java javafx

我正在使用JavaFx编写一个简单的问答游戏应用程序。我想用来自列表和表格中的数据在标签和按钮上设置文本。

我创建了三个类:Main,Controller和Quiz.fxml。我在通信类和方法上有问题。 在“ Main.java”中,我创建了对象“ Controller controller = new Controller()”,并从“ Controller.java”类中调用了方法“ controller.setText”。

现在,我有几种选择:

-如果在构造器“ public Controller(){}”应用程序中拒绝列表(ArrayList问题)和制表符(String [] []答案)不起作用,则在此行“”出现错误

-如果在“ Text()”方法(列表,标签和在标签上设置文本)应用程序中声明所有内容,但值按钮和标签未更改

-如果我在'setData()'中声明了列表和标签,然后我想从'Text()'方法中更改按钮和标签值,则看不到该列表,而我必须声明相同的列表'问题(位于Text()中)

public class Main extends Application {



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

        Parent root = FXMLLoader.load(getClass().getResource("/Controller/Quiz.fxml"));
        Scene scene = new Scene(root,500,400)
        primaryStage.setScene(scene);
        primaryStage.show();
    } catch(Exception e) {
        e.printStackTrace();
    }
}
public static void main(String[] args) {
    launch(args);
    Controller controller = new Controller();
    controller.Text();}

控制器类:

public class Controller  {

@FXML private Label questionLabel;
@FXML private RadioButton answer_btn1;
@FXML private RadioButton answer_btn2;
@FXML private RadioButton answer_btn3;
@FXML private RadioButton answer_btn4;
@FXML private Button nextBtn;



public void Text() {
    List <String> questions = new ArrayList<String>();

    questions.add("pytanie1");
    questions.add("pytanie2");
    questions.add("pytanie3");
    questions.add("pytanie4");
    questions.add("pytanie5");
    questions.add("pytanie6");
    questions.add("pytanie7");
    questions.add("pytanie8");
    questions.add("pytanie9");
    questions.add("pytanie10");

    String[][] answers = new String[1][4];
    answers[1][1] = "a) odp";
    answers[1][2] = "b) odp";
    answers[1][3] = "c) odp";
    answers[1][4] = "d) odp";


    questionLabel.setText("");

    questionLabel.setText(questionLabel.getText()+answers[1][1]);
    answer_btn1.setText("aaa");
}

我该怎么做才能更改名称按钮和标签?

2 个答案:

答案 0 :(得分:1)

您的代码有几个问题。

  1. 数组索引从零开始,如有必要,应从arrayLength-1结尾。您的代码:answers[1][1] = "a) odp"; ... answers[1][4] = "d) odp";。应该是什么:answers[0][0] = "a) odp"; ... answers[0][3] = "d) odp";
  2. 初始化Controller应该在Controller的initialize方法中完成。

下面的示例代码:

主要

import javafx.application.Application;
import javafx.fxml.FXMLLoader;
import javafx.scene.Parent;
import javafx.scene.Scene;
import javafx.stage.Stage;

/**
 *
 * @author blj0011
 */
public class JavaFXApplication226 extends Application
{

    @Override
    public void start(Stage stage) throws Exception
    {
        Parent root = FXMLLoader.load(getClass().getResource("Controller/Quiz.fxml"));

        Scene scene = new Scene(root);

        stage.setScene(scene);
        stage.show();
    }

    /**
     * @param args the command line arguments
     */
    public static void main(String[] args)
    {
        launch(args);
    }

}

控制器:

import java.net.URL;
import java.util.ArrayList;
import java.util.List;
import java.util.ResourceBundle;
import javafx.fxml.FXML;
import javafx.fxml.Initializable;
import javafx.scene.control.Button;
import javafx.scene.control.Label;
import javafx.scene.control.RadioButton;

/**
 *
 * @author blj0011
 */
public class FXMLDocumentController implements Initializable
{

    @FXML
    private Label questionLabel;
    @FXML
    private RadioButton answer_btn1;
    @FXML
    private RadioButton answer_btn2;
    @FXML
    private RadioButton answer_btn3;
    @FXML
    private RadioButton answer_btn4;
    @FXML
    private Button nextBtn;

    @Override
    public void initialize(URL url, ResourceBundle rb)
    {
        // TODO
        List<String> questions = new ArrayList();

        questions.add("pytanie1");
        questions.add("pytanie2");
        questions.add("pytanie3");
        questions.add("pytanie4");
        questions.add("pytanie5");
        questions.add("pytanie6");
        questions.add("pytanie7");
        questions.add("pytanie8");
        questions.add("pytanie9");
        questions.add("pytanie10");

        String[][] answers = new String[1][4];
        answers[0][0] = "a) odp";
        answers[0][1] = "b) odp";
        answers[0][2] = "c) odp";
        answers[0][3] = "d) odp";

        questionLabel.setText("");

        questionLabel.setText(questionLabel.getText() + answers[0][0]);
        answer_btn1.setText("aaa");
    }

}

FXML

<?xml version="1.0" encoding="UTF-8"?>

<?import javafx.scene.control.Button?>
<?import javafx.scene.control.Label?>
<?import javafx.scene.control.RadioButton?>
<?import javafx.scene.layout.AnchorPane?>

<AnchorPane id="AnchorPane" prefHeight="200" prefWidth="320" xmlns="http://javafx.com/javafx/8.0.141" xmlns:fx="http://javafx.com/fxml/1" fx:controller="javafxapplication226.FXMLDocumentController">
    <children>
        <Button fx:id="nextBtn" layoutX="118.0" layoutY="161.0" text="Click Me!" />
        <Label fx:id="questionLabel" layoutX="124.0" layoutY="36.0" minHeight="16" minWidth="69" />
      <RadioButton fx:id="answer_btn1" layoutX="47.0" layoutY="92.0" mnemonicParsing="false" text="RadioButton" />
      <RadioButton fx:id="answer_btn2" layoutX="193.0" layoutY="92.0" mnemonicParsing="false" text="RadioButton" />
      <RadioButton fx:id="answer_btn3" layoutX="47.0" layoutY="128.0" mnemonicParsing="false" text="RadioButton" />
      <RadioButton fx:id="answer_btn4" layoutX="183.0" layoutY="128.0" mnemonicParsing="false" text="RadioButton" />
    </children>
</AnchorPane>

我假设您的项目结构类似于您的代码中的以下内容。 enter image description here

答案 1 :(得分:0)

您的问题是您要实例化一个未绑定到视图的新控制器。

您可以像这样从装载机获得控制器:

FXMLLoader loader = new FXMLLoader(getClass().getResource("/Controller/Quiz.fxml"));
Parent root = loader.load();
Controller controller = loader.getController();

这样,一切都将正确连接。