我已经编写了一些动态创建JPanels的代码。我现在需要一种方法来捕获用户在这些JPanel中创建的数据。我目前有一个“创建”按钮。当被触发时，我希望这个按钮使用每个面板中的3种不同数据类型创建一个对象：name（String），count（int）和boolean。
我非常热衷于编程，但我面临的主要障碍是如何访问未命名为这些面板的动态对象？我想出了如何添加和删除它们，但我无法弄清楚从窗格中的字段捕获数据的方法。
谢谢，代码如下：
import java.awt.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.*;
import javax.swing.border.CompoundBorder;
import javax.swing.border.EmptyBorder;
import javax.swing.border.LineBorder;
public class MainSnakeGUI {
public static void main(String[] arg) {
new MainSnakeGUI();
}
public MainSnakeGUI() {
EventQueue.invokeLater(new Runnable() {
@Override
public void run() {
try {
UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
} catch (Exception e) {
e.printStackTrace();
}
//Create the frame
JFrame frame = new JFrame("Snake Channels");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.add(new SnakePane());
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
});
}
public class SnakePane extends JPanel {
public SnakePane() {
//Create buttons and labels
JButton btnAdd = new JButton("Add New Snake");
JButton btnRemove = new JButton("Delete Snake");
JLabel headerLabel = new JLabel("Create a Split Snake");
JButton btnCreate = new JButton("Create");
setLayout(new BorderLayout());
//Create JPanels
JPanel buttons = new JPanel(new FlowLayout(FlowLayout.LEFT));
JPanel header = new JPanel(new FlowLayout(FlowLayout.CENTER));
JPanel footer = new JPanel(new FlowLayout(FlowLayout.CENTER));
//add items to JPanels
buttons.add(btnAdd);
buttons.add(btnRemove);
header.add(headerLabel);
footer.add(btnCreate);
//add JPanels to window
add(header, BorderLayout.NORTH); //sets header at the top of window
header.setBorder(new CompoundBorder(new LineBorder(Color.BLACK), new EmptyBorder(10, 10, 10, 10)));
add(buttons, BorderLayout.BEFORE_LINE_BEGINS); //sets the button to the left of the display pane
buttons.setBorder(new CompoundBorder(new LineBorder(Color.BLACK), new EmptyBorder(10, 10, 10, 10)));
add(footer, BorderLayout.AFTER_LAST_LINE); //sets buttons on the bottom of window
footer.setBorder(new CompoundBorder(new LineBorder(Color.BLACK), new EmptyBorder(10, 10, 10, 10)));
//add panel to hold new frames
final JPanel content = new JPanel(new GridBagLayout());
GridBagConstraints gbc = new GridBagConstraints();
gbc.gridwidth = GridBagConstraints.REMAINDER;
gbc.weighty = 1;
content.add(new JPanel(), gbc);
//add scroll pane?
add(new JScrollPane(content));
//add listener for button
btnAdd.addActionListener(new ActionListener() {
@Override
public void actionPerformed(ActionEvent e) {
SplitSnakeCreationPane pane = new SplitSnakeCreationPane(); //create a new SnakeCreationPane
int insertAt = Math.max(0, content.getComponentCount() - 1); //insert it at the end of the list
GridBagConstraints gbc = new GridBagConstraints();
gbc.gridwidth = GridBagConstraints.REMAINDER;
gbc.fill = GridBagConstraints.HORIZONTAL;
gbc.weightx = 1;
content.add(pane, gbc, insertAt); //add the pane to the window
content.revalidate();
content.repaint();
}
});
btnRemove.addActionListener(new ActionListener() {
@Override
public void actionPerformed(ActionEvent e) {
int paneCount = content.getComponentCount()-1; //get count of the pane
content.remove(content.getComponent(paneCount-1)); //remove the pane at paneCount
content.revalidate(); //update window with changes
content.repaint();
SplitSnakeCreationPane.snakeCount--; //update count for snakes
}
});
btnCreate.addActionListener(new ActionListener() {
@Override
public void actionPerformed(ActionEvent e) {
int paneCount = content.getComponentCount()-1; //get count of the pane
for (int i=0; i<paneCount;){
}
}
});
}
//set size of window
@Override
public Dimension getPreferredSize() {
return new Dimension(1200, 400);
}
}
public static class SplitSnakeCreationPane extends JPanel {
//Count of how many snakes created
private static int snakeCount = 1;
public SplitSnakeCreationPane() {
//creates Snake Panes
setLayout(new GridLayout(2, 4, 10, 10));
add(new JLabel("Split Snake " + (snakeCount++) + "."));
add(new JLabel("Snake Name"));
add(new JLabel("Channel Count"));
add(new JLabel(""));
add(new JLabel(""));
JTextField snakeName = new JTextField(30);
JTextField channelCount = new JTextField("0",3);
JCheckBox artistSupplied = new JCheckBox("Artist Supplied?");
add(snakeName); //Snake Name field
add(channelCount); //Channel Count field
add(artistSupplied); //Artist supplied checkbox
setBorder(new CompoundBorder(new LineBorder(Color.BLACK), new EmptyBorder(10, 10, 10, 10)));
}
}
}
答案 0 :(得分：1)
您不必将这些字段作为局部变量放在构造函数中，而是需要在SplitSnakeCreationPane中使用类变量，然后添加一个公共get方法来从这些字段中获取值。只要您拥有这些get方法，就可以使用它在任何需要的地方获取字段值。
按如下方式查看修改后的类：
public static class SplitSnakeCreationPane extends JPanel {
//Count of how many snakes created
private static int snakeCount = 1;
private JTextField snakeName = null;
private JTextField channelCount = null;
private JCheckBox artistSupplied = null;
public SplitSnakeCreationPane() {
//creates Snake Panes
setLayout(new GridLayout(2, 4, 10, 10));
add(new JLabel("Split Snake " + (snakeCount++) + "."));
add(new JLabel("Snake Name"));
add(new JLabel("Channel Count"));
add(new JLabel(""));
add(new JLabel(""));
snakeName = new JTextField(30);
channelCount = new JTextField("0",3);
artistSupplied = new JCheckBox("Artist Supplied?");
add(snakeName); //Snake Name field
add(channelCount); //Channel Count field
add(artistSupplied); //Artist supplied checkbox
setBorder(new CompoundBorder(new LineBorder(Color.BLACK), new EmptyBorder(10, 10, 10, 10)));
}
public String getSnakeName() {
return snakeName.getText();
}
public String getChannelCount() {
return channelCount.getText();
}
public boolean getArtistSupplied() {
return artistSupplied.isSelected();
}
}
这是完整的代码，复制粘贴并给它一个运行：结果将打印在控制台上。希望你能了解如何获得这些价值观
import java.awt.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.*;
import javax.swing.border.CompoundBorder;
import javax.swing.border.EmptyBorder;
import javax.swing.border.LineBorder;
public class MainSnakeGUI {
public static void main(String[] arg) {
new MainSnakeGUI();
}
public MainSnakeGUI() {
EventQueue.invokeLater(new Runnable() {
@Override
public void run() {
try {
UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
} catch (Exception e) {
e.printStackTrace();
}
//Create the frame
JFrame frame = new JFrame("Snake Channels");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.add(new SnakePane());
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
});
}
public class SnakePane extends JPanel {
public SnakePane() {
//Create buttons and labels
JButton btnAdd = new JButton("Add New Snake");
JButton btnRemove = new JButton("Delete Snake");
JButton show = new JButton("show value");
JLabel headerLabel = new JLabel("Create a Split Snake");
JButton btnCreate = new JButton("Create");
setLayout(new BorderLayout());
//Create JPanels
JPanel buttons = new JPanel(new FlowLayout(FlowLayout.LEFT));
JPanel header = new JPanel(new FlowLayout(FlowLayout.CENTER));
JPanel footer = new JPanel(new FlowLayout(FlowLayout.CENTER));
//add items to JPanels
buttons.add(btnAdd);
buttons.add(btnRemove);
buttons.add(show);
header.add(headerLabel);
footer.add(btnCreate);
//add JPanels to window
add(header, BorderLayout.NORTH); //sets header at the top of window
header.setBorder(new CompoundBorder(new LineBorder(Color.BLACK), new EmptyBorder(10, 10, 10, 10)));
add(buttons, BorderLayout.BEFORE_LINE_BEGINS); //sets the button to the left of the display pane
buttons.setBorder(new CompoundBorder(new LineBorder(Color.BLACK), new EmptyBorder(10, 10, 10, 10)));
add(footer, BorderLayout.AFTER_LAST_LINE); //sets buttons on the bottom of window
footer.setBorder(new CompoundBorder(new LineBorder(Color.BLACK), new EmptyBorder(10, 10, 10, 10)));
//add panel to hold new frames
final JPanel content = new JPanel(new GridBagLayout());
GridBagConstraints gbc = new GridBagConstraints();
gbc.gridwidth = GridBagConstraints.REMAINDER;
gbc.weighty = 1;
content.add(new JPanel(), gbc);
//add scroll pane?
add(new JScrollPane(content));
//add listener for button
btnAdd.addActionListener(new ActionListener() {
@Override
public void actionPerformed(ActionEvent e) {
SplitSnakeCreationPane pane = new SplitSnakeCreationPane(); //create a new SnakeCreationPane
int insertAt = Math.max(0, content.getComponentCount() - 1); //insert it at the end of the list
GridBagConstraints gbc = new GridBagConstraints();
gbc.gridwidth = GridBagConstraints.REMAINDER;
gbc.fill = GridBagConstraints.HORIZONTAL;
gbc.weightx = 1;
content.add(pane, gbc, insertAt); //add the pane to the window
System.out.println(insertAt);
content.revalidate();
content.repaint();
}
});
btnRemove.addActionListener(new ActionListener() {
@Override
public void actionPerformed(ActionEvent e) {
int paneCount = content.getComponentCount()-1; //get count of the pane
content.remove(content.getComponent(paneCount-1)); //remove the pane at paneCount
content.revalidate(); //update window with changes
content.repaint();
SplitSnakeCreationPane.snakeCount--; //update count for snakes
}
});
show.addActionListener(new ActionListener() {
@Override
public void actionPerformed(ActionEvent e) {
for(int n=0; n<content.getComponentCount(); n++){
if(content.getComponent(n) instanceof SplitSnakeCreationPane){
SplitSnakeCreationPane com = (SplitSnakeCreationPane) content.getComponent(n);
System.out.println("Sname Name is : " + com.getSnakeName());
System.out.println("ChannelCount is : " + com.getChannelCount());
System.out.println("ArtistSupplied is : " + com.getArtistSupplied());
}
}
}
});
btnCreate.addActionListener(new ActionListener() {
@Override
public void actionPerformed(ActionEvent e) {
int paneCount = content.getComponentCount()-1; //get count of the pane
for (int i=0; i<paneCount;){
}
}
});
}
//set size of window
@Override
public Dimension getPreferredSize() {
return new Dimension(1200, 400);
}
}
public static class SplitSnakeCreationPane extends JPanel {
//Count of how many snakes created
private static int snakeCount = 1;
private JTextField snakeName = null;
private JTextField channelCount = null;
private JCheckBox artistSupplied = null;
public SplitSnakeCreationPane() {
//creates Snake Panes
setLayout(new GridLayout(2, 4, 10, 10));
add(new JLabel("Split Snake " + (snakeCount++) + "."));
add(new JLabel("Snake Name"));
add(new JLabel("Channel Count"));
add(new JLabel(""));
add(new JLabel(""));
snakeName = new JTextField(30);
channelCount = new JTextField("0",3);
artistSupplied = new JCheckBox("Artist Supplied?");
add(snakeName); //Snake Name field
add(channelCount); //Channel Count field
add(artistSupplied); //Artist supplied checkbox
setBorder(new CompoundBorder(new LineBorder(Color.BLACK), new EmptyBorder(10, 10, 10, 10)));
}
public String getSnakeName() {
return snakeName.getText();
}
public String getChannelCount() {
return channelCount.getText();
}
public boolean getArtistSupplied() {
return artistSupplied.isSelected();
}
}
}
答案 1 :(得分：0)
执行此操作的最佳方法是创建自己的自定义操作侦听器：
public class CustomListener extends ActionListener {
private List<SplitSnakeCreationPane> allPanes = new ArrayList<SplitSnakeCreationPane>();
@Override
public void actionPerformed(ActionEvent e) {
//Create your pane
//Add that pane to your 'allPanes' list.
}
public List<SplitSnakeCreationPane> getAllPanes(){
return this.allPanes;
}
}
现在您创建此类的对象并将其添加到按钮：
CustomListener createListener = new CustomListener();
btnCreate.addActionListener(createListener);
现在，如果您想要检索您添加的窗格，请致电：
List<SplitSnakeCreationPane> allPanes = createListener.getAllPanes();