我正在尝试创建一个JColorChooser对话框,在其上方带有JLabel,以便JLabel文本颜色将更改为用户使用JColorChooser选择的颜色。这是我到目前为止的内容,但尚未为我编译。
import javax.swing.*;
import java.awt.*;
import javax.swing.event.*;
public class JColorChooserExample extends JFrame
{
private JColorChooser colorChooser; // instance variables
private JLabel banner;
public JColorChooserExample() // constructor
{
add(banner = new JLabel("Welcome to the Tutorial Zone!", JLabel.CENTER), BorderLayout.NORTH);
banner.setForeground(Color.BLACK);
add(colorChooser = new JColorChooser(banner.getForeground()), BorderLayout.SOUTH);
ListenerClass listener = new ListenerClass();
colorChooser.addChangeListener(listener);
}
public static void main(String[] args)
{
JColorChooserExample frame = new JColorChooserExample(); // new frame object
frame.setTitle("JColorChooser Example"); // set frame title
frame.pack(); // sizes the frame so components fit frame
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); // ends program on frame closing
frame.setLocationRelativeTo(null); // centre frame
frame.setVisible(true); // make frame visible
}
private class ListenerClass implements ChangeListener
{
public void stateChanged(ChangeEvent e)
{
Color newColor = colorChooser.getColor();
banner.setForeground(newColor);
}
}
}
最佳答案
ChangeListener
应该在JColorChooser
的ColorSelectionModel
中注册,而不是直接在JColorChooser
本身中注册。
colorChooser.getSelectionModel().addChangeListener(listener);
How to Use Color Choosers