Java 如何在框架中单击按钮绘制图像?

Java 如何在框架中单击按钮绘制图像?,java,button,paint,Java,Button,Paint,我在框架中制作了两个按钮。我想知道如何在单击不同的按钮时显示不同的图像? 还有别的办法吗?还是我必须做一个面板?我正处于初级阶段 package prac; import java.awt.*; import java.awt.event.*; public class b extends Frame implements ActionListener{ String msg; Button one,two; b() { setSize(1000,500); setVisible

我在框架中制作了两个按钮。我想知道如何在单击不同的按钮时显示不同的图像? 还有别的办法吗?还是我必须做一个面板?我正处于初级阶段

package prac;
import java.awt.*;
import java.awt.event.*;

public class b extends Frame implements ActionListener{
String msg;
Button one,two;

b()
{   setSize(1000,500);
    setVisible(true);
    setLayout(new FlowLayout(FlowLayout.LEFT));
    one=new Button("1");
    two=new Button("2");

    add(one);
    add(two);

    one.addActionListener(this);
    two.addActionListener(this);

}
public void actionPerformed(ActionEvent e)
{
    msg=e.getActionCommand();
    if(msg.equals("1"))
    {
        msg="Pressed 1";
    }
    else
        msg="pressed 2";
repaint();      
}

public void paint(Graphics g)
{
    g.drawString(msg,100,300);
}
public static void main(String s[])
{
    new b();
}
}

使用
JLabel
并在单击按钮时更改图标

有几点:

  • 添加所有组件后,最后调用
    setVisible(true)
  • 使用
    JFrame#pack()
示例代码:

final JLabel jlabel = new JLabel();
add(jlabel);

final Image image1 = ImageIO.read(new File("resources/1.png"));
final Image image2 = ImageIO.read(new File("resources/2.png"));

JPanel panel = new JPanel();
JButton jbutton1 = new JButton("Show first image");
jbutton1.addActionListener(new ActionListener() {

    @Override
    public void actionPerformed(ActionEvent arg0) {
        jlabel.setIcon(new ImageIcon(image1));
    }
});

JButton jbutton2 = new JButton("Show second image");
jbutton2.addActionListener(new ActionListener() {

    @Override
    public void actionPerformed(ActionEvent arg0) {
        jlabel.setIcon(new ImageIcon(image2));
    }
});

panel.add(jbutton1);
panel.add(jbutton2);
add(panel, BorderLayout.NORTH);

答案对你有帮助吗。