我希望另一组眼睛可以帮助我找到我的代码出错的地方。我可以编译和运行该程序,但我得到的只是一个白色屏幕。它应该显示复选框并将背景更改为选择的颜色。任何帮助表示赞赏!复选框未显示
import javax.swing.JOptionPane;
import java.awt.*;
import java.awt.event.*;
public class Chapter5Debug extends Frame implements ItemListener
{
static Chapter5Debug f = new Chapter5Debug();
CheckboxGroup options = new CheckboxGroup();
Checkbox blue = new Checkbox("Blue",false,options);
Checkbox red = new Checkbox("Red",false,options);
Checkbox yellow = new Checkbox("Yellow",false,options);
Checkbox pink = new Checkbox("Pink",false,options);
Checkbox gray = new Checkbox("Gray",false,options);
public void Chapter5Debug()
{
this.setLayout(new FlowLayout());
add(blue);
add(red);
add(yellow);
add(pink);
add(gray);
blue.addItemListener(this);
red.addItemListener(this);
yellow.addItemListener(this);
pink.addItemListener(this);
gray.addItemListener(this);
//overriding windowClosing() allows user to click Close button
addWindowListener(
new WindowAdapter()
{
public void windowClosing(WindowEvent e)
{
System.exit(0);
}
}
);
} //end of constructor method
public static void main(String[] args)
{
//ColorButtons f = new ColorButtons();
f.setBounds(200,200,500,100);
f.setTitle("What's My Color?");
f.setVisible(true);
} //end of main
public void actionPerformed(ActionEvent e)
{
if (blue.getState()) f.setBackground(Color.blue);
else if (red.getState()) f.setBackground(Color.red);
else if (yellow.getState()) f.setBackground(Color.yellow);
else if (pink.getState()) f.setBackground(Color.pink);
else if (gray.getState()) f.setBackground(Color.gray);
} //end of actionPerformed method
public void itemStateChanged(ItemEvent e)
{
}
} //end of class
您有敏锐的眼睛 – chancea
谢谢。我删除了空白,可以看到颜色复选框,但背景仍然是白色的。欣赏你敏锐的眼睛:-) –