Question

我正在尝试将一些监听器放在我的代码中，但我不能。例如，我想添加一个监听器，当我在文本区域中编写somenthing时，我选择JRadioButton“From TextField”，之后我按下“Do It”按钮，我想看到我写的文本（在JTextArea上的TextField）。怎么可能？

    import javax.swing.*;
    import java.awt.*;
    import java.awt.event.*;
    import javafx.scene.Group;

    public class Layout {
    final static boolean shouldFill = true;
    final static boolean shouldWeightX = true;
    final static boolean RIGHT_TO_LEFT = false;
    public static void addComponentsToPane(Container pane) {
        if (RIGHT_TO_LEFT) {
            pane.setComponentOrientation(ComponentOrientation.RIGHT_TO_LEFT);}

        JButton button;
    pane.setLayout(new GridBagLayout());
    GridBagConstraints c = new GridBagConstraints();
        GridBagConstraints c1 = new GridBagConstraints();

    if (shouldFill) {
    c.fill = GridBagConstraints.HORIZONTAL;}
    JTextField text = new JTextField( "Some Text");
    if (shouldWeightX) {
    c.weightx = 0.5;}
    c.fill = GridBagConstraints.HORIZONTAL;
    c.gridx = 0;
    c.gridy = 0;
        c.ipady = 50;
    pane.add(text, c);

    String names[] = { "Ferrari", "Koenigsegg", "Alfa Romeo" };
        JComboBox cb = new JComboBox( names );
    c.fill = GridBagConstraints.HORIZONTAL;
    c.weightx = 0.5;
    c.gridx = 1;
    c.gridy = 0;
        c.ipady = 50;
    pane.add(cb, c);

        Box box=Box.createVerticalBox();

    JCheckBox checkbox = new JCheckBox("Water");
        JCheckBox checkbox2 = new JCheckBox("Fire");
        JCheckBox checkbox3 = new JCheckBox("Earth");

        c1.fill = GridBagConstraints.HORIZONTAL;
        c1.weightx = 0.5;
        c1.ipady = 5;

        box.add(checkbox);
        box.add(checkbox2);
        box.add(checkbox3);

        pane.add(box,c1);

    JPanel container = new JPanel();    
    container.setBorder(BorderFactory.createEmptyBorder(20,20,20,20));
    container.setLayout(new GridLayout(2, 1));
    JSlider slider = new JSlider(JSlider.HORIZONTAL,0,100,50);
    slider.setPreferredSize(new Dimension(150,20));
    slider.setMinorTickSpacing(1);  
    slider.setMajorTickSpacing(10);  
    slider.setPaintTicks(true);  
    slider.setPaintLabels(true);  

    c.fill = GridBagConstraints.HORIZONTAL;
    c.ipady = 40;     
    c.weightx = 0.0;
    c.gridwidth = 3;
    c.gridx = 0;
    c.gridy = 1;
    pane.add(slider, c);

    JTextField text1 = new JTextField(" ");
    c.ipady = 80;     
    c.weighty = 2.0;
        c.anchor = GridBagConstraints.BASELINE; 
    c.gridx = 0;      
    c.gridwidth = 3;   
    c.gridy = 2;       
    pane.add(text1, c);


        JRadioButton b1= new JRadioButton("From JTextField");
        JRadioButton b2= new JRadioButton("From JComboBox");
        JRadioButton b3= new JRadioButton("From JCheckboxes");
        JRadioButton b4= new JRadioButton("J Slider");

        b1.setForeground(Color.BLUE);
        b2.setForeground(Color.RED);
        b3.setBackground(Color.GREEN);
         Box box1 = Box.createHorizontalBox();

      box1.add(b1);
      box1.add(b2);
      box1.add(b3);
      box1.add(b4);

        c.fill = GridBagConstraints.HORIZONTAL;
        c.ipady = 10;     
    c.weighty = 1.0; 
        c.anchor = GridBagConstraints.BASELINE; 
    c.gridx = 0;      
    c.gridwidth = 3;   
    c.gridy =2; 

            pane.add(box1,c);

    button = new JButton("Do it");
    c.fill = GridBagConstraints.HORIZONTAL;
    c.ipady =0;     
    c.weighty = 1.0;   
    c.anchor = GridBagConstraints.PAGE_END; 
    c.insets = new Insets(10,0,0,0); 
    c.gridx = 0;      
    c.gridwidth =3;   
    c.gridy = 2;       
    pane.add(button, c);
    }

    private static void createAndShowGUI() {

        JFrame frame = new JFrame(" ");
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

        addComponentsToPane(frame.getContentPane());

        frame.pack();
        frame.setVisible(true);
        frame.setSize(600,400);
    }



    public static void main(String[] args) {

        javax.swing.SwingUtilities.invokeLater(new Runnable() {
            public void run() {
                createAndShowGUI();
            }
        });   
}

    }

Answer 1

阅读How to Use Text Areas上的Swing教程中的部分。第一个示例显示如何将文本从JTextField附加到JTextArea。此示例使用ActionListener作为文本字段。

然后我选择JRadioButton“From TextField”，之后我按下“Do It”按钮，我想看到我在JTextArea上写的文本（在TextField中）。

除了将ActionListener添加到按钮之外，概念将类似。然后在调用它时，检查是否选中了“From TextField”单选按钮。如果是这样，那么您将从文本字段中获取文本并将其附加到文本区域。

无法添加监听器

1 个答案: