返回先前的JPanel [英] Go back to prior JPanel
问题描述
我已经继承了代码，出于长时间解释的原因，我必须使用null布局.我一直在尝试让他们在JPanels之间进行导航.我还没办法弄清楚.这就是我现在将其分解为以下SSCCE的内容.我试图做的是将JPanels添加到ArrayList，其中包含对先前JPanels的引用.这样，我可以从用户所在的当前JPanel调用本地" JPanel.到目前为止，它转到了以前的JPanel，但是内容为空.任何帮助都会很棒，谢谢！
I have inherited code and for reasons to long to explain I am required to use a null layout. I have been attempting to take what they have an navigate between JPanels. I haven't been able to figure out how. This is what I have now which compiles broken down into a SSCCE below. What I am attempting to do is add the JPanels to an ArrayList which contains a reference to previous JPanels. That way I can call a "home" JPanel from the current JPanel the user is in. As of now it goes to the previous JPanel but the contents are empty. Any help would be great, THANKS!
import java.util.ArrayList;
import javax.swing.*;
import javax.swing.border.LineBorder;
import java.awt.*;
import java.awt.event.ActionListener;
import java.awt.event.ActionEvent;
public class Mainscreen extends JFrame {
public JPanel Home;
public static void main(String[] args) {
EventQueue.invokeLater(new Runnable() {
public void run() {
try {
Mainscreen frame = new Mainscreen();
frame.setVisible(true);
}
catch (Exception e) {
e.printStackTrace();
}
}
});
}
public Mainscreen() {
ArrayList <JPanel> jpLayout = new ArrayList();
final Dataentrylog DEL = new Dataentrylog(this, jpLayout);
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
setResizable(false);
setBounds(100, 100, 618, 373);
Home=new JPanel();
Home.setBackground(new Color(255, 250, 250));
Home.setBorder(new LineBorder(Color.DARK_GRAY, 1, true));
Home.setVisible(true);
setContentPane(Home);
Home.setLayout(null);
JButton delLog = new JButton("Next JPanel");
delLog.setFont(new Font("Tahoma", Font.PLAIN, 14));
delLog.setForeground(new Color(0, 0, 0));
delLog.setBackground(UIManager.getColor("Menu.selectionBackground"));
Home.add(delLog);
jpLayout.add(Home);
delLog.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent arg0) {
Home.setVisible(false);
setContentPane(DEL);
getContentPane().setLayout(null);
}
});
delLog.setBounds(44, 214, 213, 61);
}
}
import java.util.ArrayList;
import javax.swing.*;
import javax.swing.border.LineBorder;
import java.awt.*;
import java.awt.event.ActionListener;
import java.awt.event.ActionEvent;
public class Dataentrylog extends JPanel {
public Dataentrylog(final JFrame parent, final ArrayList <JPanel> jpLayout) {
setBounds(100, 100, 618, 373);
setBackground(new Color(255, 250, 250));
setBorder(new LineBorder(Color.DARK_GRAY, 1, true));
setLayout(null);
final JButton btnSignIn = new JButton("Go Back");
btnSignIn.setFont(new Font("Tahoma", Font.PLAIN, 14));
btnSignIn.setBackground(UIManager.getColor("EditorPane.selectionBackground"));
btnSignIn.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
setVisible(false);
parent.setContentPane(jpLayout.get(0));
setLayout(null);
}
});
btnSignIn.setBounds(226, 282, 153, 52);
add(btnSignIn);
}
}
推荐答案
我必须使用空布局.
I am required to use a null layout.
如果某些指导者要求您使用null layout在面板之间进行导航，则需要执行以下操作:
If you are asked by some mentor to perform navigation among panels using null layout, here is what you need to do:
- 首先，离开导师.
- 第二，使用CardLayout.
- First, leave the mentor.
- Second, use CardLayout.
查看教程:如何使用CardLayout
工作示例:
这是书面的CardLayoutDemo，它可以使用按钮单击操作在10 panels(包括主页"面板)之间导航:
here is a written CardLayoutDemo which navigates among 10 panels including Home panel using button click action:
import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
class CardLayoutDemo1 extends JFrame {
private JPanel jPanel1;
private JButton navHomeButt;
private JButton navNextButt;
private JButton navPreviousButt;
private JPanel panelContainer;
public CardLayoutDemo1() {
initComponents();
panelContainer.add(createSamplePanel("Home Panel "), ""+0);
for(int i=1; i < 10; i++)
{
panelContainer.add(createSamplePanel("Panel "+i), ""+i);
}
}
private void initComponents() {
jPanel1 = new javax.swing.JPanel();
navPreviousButt = new JButton();
navNextButt = new JButton();
navHomeButt = new JButton();
panelContainer = new JPanel();
setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE);
jPanel1.setBackground(new java.awt.Color(255, 255, 255));
navPreviousButt.setText("Previous");
navPreviousButt.setPreferredSize(new Dimension(90, 23));
jPanel1.add(navPreviousButt);
navNextButt.setText("next");
navNextButt.setPreferredSize(new Dimension(90, 23));
jPanel1.add(navNextButt);
navHomeButt.setText("Back to Home");
jPanel1.add(navHomeButt);
panelContainer.setPreferredSize(new Dimension(400, 300));
panelContainer.setLayout(new CardLayout());
// setting the card layout
getContentPane().add(jPanel1, java.awt.BorderLayout.PAGE_END);
getContentPane().add(panelContainer, BorderLayout.CENTER);
navNextButt.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent evt) {
CardLayout cardLayout = (CardLayout) panelContainer.getLayout();
cardLayout.next(panelContainer);
// using cardLayout next() to go to next panel
}
});
navHomeButt.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent evt) {
CardLayout cardLayout = (CardLayout) panelContainer.getLayout();
cardLayout.first(panelContainer);
// suing first to get to the home panel
}
});
navPreviousButt.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent evt) {
CardLayout cardLayout = (CardLayout) panelContainer.getLayout();
cardLayout.previous(panelContainer);
// using previous to get to previous(left)panel
}
});
pack();
}
public JPanel createSamplePanel(String panelTitle)
{
JPanel samplePanel = new JPanel();
samplePanel.add(new JLabel(panelTitle));
return samplePanel;
}
public static void main(String args[]) {
java.awt.EventQueue.invokeLater(new Runnable() {
public void run() {
new CardLayoutDemo1().setVisible(true);
}
});
}
}
这篇关于返回先前的JPanel的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！
