Java:对 Button 使用 setText() 方法时出现问题

Question

我是 java 新手，我正在尝试交换我创建的按钮上的文本。我的主类的代码如下:

import java.applet.*;
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import java.lang.*;

public class TeamProject extends Applet implements ActionListener, MouseListener
{
char[][] charValues = new char[10][10];
Table aTable;
boolean allowUserInput = false;
Button BtnStart;
Button randomChangeBtn;
boolean guessMode;
private AudioClip[] sounds = new AudioClip[5];
private int counter = 0;
//JSObject jso;

public void init()
{
        //setup buttons
    BtnStart = new Button("add row/column");
    BtnStart.addActionListener((ActionListener)this);   //cast
    randomChangeBtn = new Button("change one value");
    randomChangeBtn.addActionListener((ActionListener)this);

            //add button
    this.add(BtnStart);

    //add image to Image objects
    Image imgO = getImage(getCodeBase(), "images/not.gif");
    Image imgX= getImage(getCodeBase(), "images/cross.gif");

            //setup table
    aTable = new Table(100, 100, 75, 55, 5, 5, imgX, imgO);

    //setBackground(Color.LIGHT_GRAY);
    super.resize(700, 700);

            //add mouse listener
    addMouseListener(this);

    //initially guessMode will be false
    guessMode = false;

            //to talk to javascript
    //jso = JSObject.getWindow(this);

    sounds[0] = getAudioClip (getCodeBase(), "images/buzzthruloud.wav");
    sounds[1] = getAudioClip (getCodeBase(), "images/inconceivable4.wav");
    sounds[2] = getAudioClip (getCodeBase(), "images/foghorn.wav");
    sounds[3] = getAudioClip (getCodeBase(), "images/waiting.wav");
    sounds[4] = getAudioClip (getCodeBase(), "images/whistldn.wav");
}

  public void paint(Graphics g)
  {
g.setColor(Color.black);
aTable.draw(g);
  }

  //Mouse listener methods
  public void mousePressed (MouseEvent e)
  {
    if(!guessMode){
  if ((allowUserInput)){
    aTable.swapSquareValue(e.getX(), e.getY());
    repaint();
  }
    }
    else{
      System.out.println("guessed row = " + e.getY() + " guessed col = " + e.getX());
      if(aTable.checkGuess(e.getX(), e.getY())){
        int n = JOptionPane.showConfirmDialog(null, "Excellent!! Would you like to progress to next level",

                                         "Correct!!!", JOptionPane.YES_NO_OPTION);

    if (n == JOpionPane.YES_OPTION) {


               }
 else{

    JOptionPane.showMessageDialog(null, "Nope", "alert", JOptionPane.INFORMATION_MESSAGE);

    sounds[counter].play();

  }



  //repaint();

}



  }



  public void mouseClicked (MouseEvent e) {}

  public void mouseEntered (MouseEvent e) {}

  public void mouseReleased (MouseEvent e) {}

  public void mouseExited (MouseEvent e) {}



  //Button action listener

public void actionPerformed(ActionEvent e)

{

    if (e.getSource() == BtnStart) {

      aTable.addRow();

      aTable.addColumn();

      BtnStart.setText("Roseindia.net");

      //this.remove(BtnStart);

      //this.add(randomChangeBtn);

      super.resize(700, 700);

      repaint();

}

else if (e.getSource() == randomChangeBtn) {

  aTable.randomChangeFunc();

  repaint();

  guessMode = true;

}



    allowUserInput = true;

    System.out.println(aTable.toString());

}



}

我正在尝试在我的actionPerformed(ActionEvent e) 方法中更改为文本。就像我说的，我是新人，所以请温柔点。谢谢:)

Answer 1

您正在使用java.awt.Button。 java.awt.Button 中没有 setText() 方法。您可以使用 setLabel(String) 代替。

而且您也不必导入 java.lang.*，因为默认情况下 java.lang 包可供所有 Java 程序使用。

如果你改变线路:

 Button BtnStart;

到

 JButton BtnStart;

和

 BtnStart = new Button("add row/column");

到

 BtnStart = new JButton("add row/column");

然后您将使用 Swing Button，并且您将能够调用 setText();