JProgressBar完成后如何打开新的window
How to open new window after JProgressBar is completed
我创建了 FlashScreen.java 作为加载屏幕由 JProgressBar 组成。
我希望进度条百分比完成后，当前 window 应该关闭，新 window 应该打开。
我做到了，但是在关闭第一个 window 之后 window 之后 window 中没有组件。空window正在开盘。
这是代码：
FlashScreen.java
package crimeManagement;
import javax.swing.*;
import java.awt.Rectangle;
import java.awt.Font;
import java.awt.Color;
import java.awt.event.ActionListener;
import java.awt.event.ActionEvent;
public class FlashScreen extends JFrame{
JProgressBar jb;
JLabel lblStat;
int i=0,num=0;
FlashScreen(){
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
setResizable(false);
setBounds(new Rectangle(400, 200, 0, 0));
jb=new JProgressBar(0,2000);
jb.setBounds(100,219,579,22);
jb.setValue(0);
jb.setStringPainted(true);
getContentPane().add(jb);
setSize(804,405);
getContentPane().setLayout(null);
lblStat = new JLabel("");
lblStat.setForeground(Color.CYAN);
lblStat.setHorizontalAlignment(SwingConstants.CENTER);
lblStat.setHorizontalTextPosition(SwingConstants.CENTER);
lblStat.setFont(new Font("Tahoma", Font.BOLD | Font.ITALIC, 18));
lblStat.setBounds(229, 252, 329, 14);
getContentPane().add(lblStat);
JLabel lblBackGround = new JLabel("");
lblBackGround.setHorizontalTextPosition(SwingConstants.CENTER);
lblBackGround.setHorizontalAlignment(SwingConstants.CENTER);
lblBackGround.setIcon(new ImageIcon(FlashScreen.class.getResource("/Images/FlashImage.jpg")));
lblBackGround.setBounds(0, 0, 798, 376);
getContentPane().add(lblBackGround);
}
public void iterate(){
while(i<=2000){
jb.setValue(i);
i=i+20;
try{
Thread.sleep(50);
if(i==20)
{
lblStat.setText("Loading...");
}
if(i==500)
{
lblStat.setText("Please Wait...");
}
if(i==1000)
{
Thread.sleep(100);
lblStat.setText("Loading Police Station Management System...");
}
if(i==1200)
{
lblStat.setText("Please Wait...");
}
if(i==1600)
{
lblStat.setText("Almost Done...");
}
if(i==1980)
{
lblStat.setText("Done");
}
if(i==2000)
{
this.dispose();
LoginPage lp=new LoginPage();
lp.setVisible(true);
}
}
catch(Exception e){}
}
}
public static void main(String[] args) {
FlashScreen fs=new FlashScreen();
fs.setVisible(true);
fs.iterate();
}
}
**LoginPage.java**
package crimeManagement;
import javax.swing.*;
import java.awt.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.border.*;
public class LoginPage extends JFrame {
/**
*
*/
private static final long serialVersionUID = 1L;
private JFrame frame;
private JTextField txtUserName;
private JPasswordField txtPass;
public static void main(String[] args) {
LoginPage window = new LoginPage();
window.frame.setVisible(true);
}
public LoginPage() {
frame = new JFrame();
frame.setResizable(false);
frame.getContentPane().setBackground(SystemColor.inactiveCaption);
frame.getContentPane().setFont(new Font("Tahoma", Font.PLAIN, 16));
frame.setBounds(100, 100, 554, 410);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.getContentPane().setLayout(null);
JLabel lblLoginType = new JLabel("Login Type");
lblLoginType.setFont(new Font("Tahoma", Font.PLAIN, 16));
lblLoginType.setBounds(97, 53, 99, 20);
frame.getContentPane().add(lblLoginType);
JLabel lblUsename = new JLabel("User Name");
lblUsename.setFont(new Font("Tahoma", Font.PLAIN, 16));
lblUsename.setBounds(97, 177, 99, 26);
frame.getContentPane().add(lblUsename);
JLabel lblPaaword = new JLabel("Password");
lblPaaword.setFont(new Font("Tahoma", Font.PLAIN, 16));
lblPaaword.setBounds(97, 223, 99, 26);
frame.getContentPane().add(lblPaaword);
JPanel panel = new JPanel();
FlowLayout flowLayout = (FlowLayout) panel.getLayout();
panel.setBackground(SystemColor.inactiveCaptionBorder);
panel.setBounds(210, 47, 143, 93);
frame.getContentPane().add(panel);
TitledBorder tb=new TitledBorder( "Login");
tb.setTitleJustification(TitledBorder.CENTER);
tb.setTitlePosition(TitledBorder.CENTER);
panel.setBorder(BorderFactory.createTitledBorder(tb));
JRadioButton rdbAdmin = new JRadioButton("Admin");
rdbAdmin.setBackground(SystemColor.inactiveCaption);
rdbAdmin.setFont(new Font("Tahoma", Font.PLAIN, 13));
rdbAdmin.setSelected(true);
panel.add(rdbAdmin);
JRadioButton rdbOthers = new JRadioButton("Others");
rdbOthers.setBackground(SystemColor.inactiveCaption);
rdbOthers.setFont(new Font("Tahoma", Font.PLAIN, 13));
panel.add(rdbOthers);
txtUserName = new JTextField();
txtUserName.setBackground(UIManager.getColor("TextField.background"));
txtUserName.setBounds(210, 177, 158, 26);
frame.getContentPane().add(txtUserName);
txtUserName.setColumns(30);
JButton btnLogin = new JButton("Login");
btnLogin.setFont(new Font("Tahoma", Font.PLAIN, 14));
btnLogin.setBounds(210, 286, 71, 23);
frame.getContentPane().add(btnLogin);
JButton btnExit = new JButton("Exit");
btnExit.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent arg0) {
System.exit(0);
}
});
btnExit.setFont(new Font("Tahoma", Font.PLAIN, 14));
btnExit.setBounds(297, 286, 71, 23);
frame.getContentPane().add(btnExit);
txtPass = new JPasswordField();
txtPass.setBounds(210, 226, 158, 26);
frame.getContentPane().add(txtPass);
}
}
您显示的是错误的 JFrame。是的，LoginPage 扩展了 JFrame，是的，您显示了它，但没有向它添加任何组件，而是将所有组件添加到名为 class 的私有 JFrame 字段中，frame。
一个快速的解决方案是更改您的 LoginPage class，这样它就不会扩展 JFrame，然后给这个 class 一个 public getFrame() 方法：
public JFrame getFrame() {
return frame;
}
想显示的时候调用
this.dispose();
LoginPage lp = new LoginPage();
// lp.setVisible(true);
lp.getFrame().setVisible(true);
但话虽如此，您的代码仍然存在一些您最终想要修复的严重线程问题，包括尝试避免在可能在 Swing 事件线程上调用的代码中调用 Thread.sleep() .
另请查看 The Use of Multiple JFrames: Good or Bad Practice? 以了解为什么在您的应用程序中显示一堆 JFrame 通常是一种不好的做法，以及解决此问题的方法。
其他问题包括使用空布局。是的，它们看起来像是一种快速创建复杂 GUI 的简单方法——直到您尝试在另一个平台上显示 GUI 并发现它们看起来不太好，或者必须增强、调试或更改它，并且发现它非常好棘手且容易搞砸。使用布局管理器要好得多。
import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.Font;
import java.awt.GridLayout;
import java.awt.Window;
import java.awt.Dialog.ModalityType;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.*;
public class FlashScreenTest {
public static void main(String[] args) {
SwingUtilities.invokeLater(() -> {
JFrame mainFrame = new JFrame("Main App");
mainFrame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
mainFrame.add(new MainAppPanel());
mainFrame.pack();
mainFrame.setLocationRelativeTo(null);
FlashScreenPanel dialogPanel = new FlashScreenPanel();
JDialog dialog = new JDialog(mainFrame, "Flash Screen", ModalityType.APPLICATION_MODAL);
dialog.add(dialogPanel);
dialog.pack();
dialog.setLocationRelativeTo(null);
dialogPanel.startProgress();
dialog.setVisible(true);
mainFrame.setVisible(true);
});
}
}
class FlashScreenPanel extends JPanel {
public static final String LOADING = "Loading...";
public static final String PLEASE_WAIT = "Please Wait...";
public static final String LOADING_POLICE_STATION = "Loading Police Station...";
public static final String ALMOST_DONE = "Almost Done...";
public static final String DONE = "Done";
private static final int TIMER_DELAY = 50;
private JProgressBar jb = new JProgressBar(0, 2000);
private JLabel statusLabel = new JLabel("", SwingConstants.CENTER);
public FlashScreenPanel() {
setPreferredSize(new Dimension(800, 400));
statusLabel.setForeground(Color.CYAN);
statusLabel.setFont(new Font("Tahoma", Font.BOLD | Font.ITALIC, 18));
jb.setStringPainted(true);
JPanel bottomPanel = new JPanel(new BorderLayout(20, 20));
bottomPanel.add(jb, BorderLayout.PAGE_START);
bottomPanel.add(statusLabel, BorderLayout.CENTER);
int eb = 40;
setBorder(BorderFactory.createEmptyBorder(eb, eb, eb, eb));
setLayout(new GridLayout(0, 1));
add(new JLabel()); // dummy component to move prog bar lower
add(bottomPanel);
}
public void startProgress() {
statusLabel.setText(LOADING);
new Timer(TIMER_DELAY, new ActionListener() {
private int i = 0;
@Override
public void actionPerformed(ActionEvent e) {
i += 20;
jb.setValue(i);
if (i == 500) {
statusLabel.setText(PLEASE_WAIT);
} else
if (i == 1000) {
statusLabel.setText(LOADING_POLICE_STATION);
} else
if (i == 1200) {
statusLabel.setText(PLEASE_WAIT);
} else
if (i == 1600) {
statusLabel.setText(ALMOST_DONE);
} else
if (i == 1980) {
statusLabel.setText(DONE);
} else
if (i == 2000) {
((Timer) e.getSource()).stop();
Window win = SwingUtilities.getWindowAncestor(FlashScreenPanel.this);
win.dispose();
}
}
}).start();
}
}
class MainAppPanel extends JPanel {
public MainAppPanel() {
setPreferredSize(new Dimension(600, 400));
}
}
我创建了 FlashScreen.java 作为加载屏幕由 JProgressBar 组成。 我希望进度条百分比完成后，当前 window 应该关闭，新 window 应该打开。 我做到了，但是在关闭第一个 window 之后 window 之后 window 中没有组件。空window正在开盘。
这是代码： FlashScreen.java
package crimeManagement;
import javax.swing.*;
import java.awt.Rectangle;
import java.awt.Font;
import java.awt.Color;
import java.awt.event.ActionListener;
import java.awt.event.ActionEvent;
public class FlashScreen extends JFrame{
JProgressBar jb;
JLabel lblStat;
int i=0,num=0;
FlashScreen(){
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
setResizable(false);
setBounds(new Rectangle(400, 200, 0, 0));
jb=new JProgressBar(0,2000);
jb.setBounds(100,219,579,22);
jb.setValue(0);
jb.setStringPainted(true);
getContentPane().add(jb);
setSize(804,405);
getContentPane().setLayout(null);
lblStat = new JLabel("");
lblStat.setForeground(Color.CYAN);
lblStat.setHorizontalAlignment(SwingConstants.CENTER);
lblStat.setHorizontalTextPosition(SwingConstants.CENTER);
lblStat.setFont(new Font("Tahoma", Font.BOLD | Font.ITALIC, 18));
lblStat.setBounds(229, 252, 329, 14);
getContentPane().add(lblStat);
JLabel lblBackGround = new JLabel("");
lblBackGround.setHorizontalTextPosition(SwingConstants.CENTER);
lblBackGround.setHorizontalAlignment(SwingConstants.CENTER);
lblBackGround.setIcon(new ImageIcon(FlashScreen.class.getResource("/Images/FlashImage.jpg")));
lblBackGround.setBounds(0, 0, 798, 376);
getContentPane().add(lblBackGround);
}
public void iterate(){
while(i<=2000){
jb.setValue(i);
i=i+20;
try{
Thread.sleep(50);
if(i==20)
{
lblStat.setText("Loading...");
}
if(i==500)
{
lblStat.setText("Please Wait...");
}
if(i==1000)
{
Thread.sleep(100);
lblStat.setText("Loading Police Station Management System...");
}
if(i==1200)
{
lblStat.setText("Please Wait...");
}
if(i==1600)
{
lblStat.setText("Almost Done...");
}
if(i==1980)
{
lblStat.setText("Done");
}
if(i==2000)
{
this.dispose();
LoginPage lp=new LoginPage();
lp.setVisible(true);
}
}
catch(Exception e){}
}
}
public static void main(String[] args) {
FlashScreen fs=new FlashScreen();
fs.setVisible(true);
fs.iterate();
}
}
**LoginPage.java**
package crimeManagement;
import javax.swing.*;
import java.awt.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.border.*;
public class LoginPage extends JFrame {
/**
*
*/
private static final long serialVersionUID = 1L;
private JFrame frame;
private JTextField txtUserName;
private JPasswordField txtPass;
public static void main(String[] args) {
LoginPage window = new LoginPage();
window.frame.setVisible(true);
}
public LoginPage() {
frame = new JFrame();
frame.setResizable(false);
frame.getContentPane().setBackground(SystemColor.inactiveCaption);
frame.getContentPane().setFont(new Font("Tahoma", Font.PLAIN, 16));
frame.setBounds(100, 100, 554, 410);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.getContentPane().setLayout(null);
JLabel lblLoginType = new JLabel("Login Type");
lblLoginType.setFont(new Font("Tahoma", Font.PLAIN, 16));
lblLoginType.setBounds(97, 53, 99, 20);
frame.getContentPane().add(lblLoginType);
JLabel lblUsename = new JLabel("User Name");
lblUsename.setFont(new Font("Tahoma", Font.PLAIN, 16));
lblUsename.setBounds(97, 177, 99, 26);
frame.getContentPane().add(lblUsename);
JLabel lblPaaword = new JLabel("Password");
lblPaaword.setFont(new Font("Tahoma", Font.PLAIN, 16));
lblPaaword.setBounds(97, 223, 99, 26);
frame.getContentPane().add(lblPaaword);
JPanel panel = new JPanel();
FlowLayout flowLayout = (FlowLayout) panel.getLayout();
panel.setBackground(SystemColor.inactiveCaptionBorder);
panel.setBounds(210, 47, 143, 93);
frame.getContentPane().add(panel);
TitledBorder tb=new TitledBorder( "Login");
tb.setTitleJustification(TitledBorder.CENTER);
tb.setTitlePosition(TitledBorder.CENTER);
panel.setBorder(BorderFactory.createTitledBorder(tb));
JRadioButton rdbAdmin = new JRadioButton("Admin");
rdbAdmin.setBackground(SystemColor.inactiveCaption);
rdbAdmin.setFont(new Font("Tahoma", Font.PLAIN, 13));
rdbAdmin.setSelected(true);
panel.add(rdbAdmin);
JRadioButton rdbOthers = new JRadioButton("Others");
rdbOthers.setBackground(SystemColor.inactiveCaption);
rdbOthers.setFont(new Font("Tahoma", Font.PLAIN, 13));
panel.add(rdbOthers);
txtUserName = new JTextField();
txtUserName.setBackground(UIManager.getColor("TextField.background"));
txtUserName.setBounds(210, 177, 158, 26);
frame.getContentPane().add(txtUserName);
txtUserName.setColumns(30);
JButton btnLogin = new JButton("Login");
btnLogin.setFont(new Font("Tahoma", Font.PLAIN, 14));
btnLogin.setBounds(210, 286, 71, 23);
frame.getContentPane().add(btnLogin);
JButton btnExit = new JButton("Exit");
btnExit.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent arg0) {
System.exit(0);
}
});
btnExit.setFont(new Font("Tahoma", Font.PLAIN, 14));
btnExit.setBounds(297, 286, 71, 23);
frame.getContentPane().add(btnExit);
txtPass = new JPasswordField();
txtPass.setBounds(210, 226, 158, 26);
frame.getContentPane().add(txtPass);
}
}
您显示的是错误的 JFrame。是的，LoginPage 扩展了 JFrame，是的，您显示了它，但没有向它添加任何组件，而是将所有组件添加到名为 class 的私有 JFrame 字段中，frame。
一个快速的解决方案是更改您的 LoginPage class，这样它就不会扩展 JFrame，然后给这个 class 一个 public getFrame() 方法：
public JFrame getFrame() {
return frame;
}
想显示的时候调用
this.dispose();
LoginPage lp = new LoginPage();
// lp.setVisible(true);
lp.getFrame().setVisible(true);
但话虽如此，您的代码仍然存在一些您最终想要修复的严重线程问题，包括尝试避免在可能在 Swing 事件线程上调用的代码中调用 Thread.sleep() .
另请查看 The Use of Multiple JFrames: Good or Bad Practice? 以了解为什么在您的应用程序中显示一堆 JFrame 通常是一种不好的做法，以及解决此问题的方法。
其他问题包括使用空布局。是的，它们看起来像是一种快速创建复杂 GUI 的简单方法——直到您尝试在另一个平台上显示 GUI 并发现它们看起来不太好，或者必须增强、调试或更改它，并且发现它非常好棘手且容易搞砸。使用布局管理器要好得多。
import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.Font;
import java.awt.GridLayout;
import java.awt.Window;
import java.awt.Dialog.ModalityType;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.*;
public class FlashScreenTest {
public static void main(String[] args) {
SwingUtilities.invokeLater(() -> {
JFrame mainFrame = new JFrame("Main App");
mainFrame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
mainFrame.add(new MainAppPanel());
mainFrame.pack();
mainFrame.setLocationRelativeTo(null);
FlashScreenPanel dialogPanel = new FlashScreenPanel();
JDialog dialog = new JDialog(mainFrame, "Flash Screen", ModalityType.APPLICATION_MODAL);
dialog.add(dialogPanel);
dialog.pack();
dialog.setLocationRelativeTo(null);
dialogPanel.startProgress();
dialog.setVisible(true);
mainFrame.setVisible(true);
});
}
}
class FlashScreenPanel extends JPanel {
public static final String LOADING = "Loading...";
public static final String PLEASE_WAIT = "Please Wait...";
public static final String LOADING_POLICE_STATION = "Loading Police Station...";
public static final String ALMOST_DONE = "Almost Done...";
public static final String DONE = "Done";
private static final int TIMER_DELAY = 50;
private JProgressBar jb = new JProgressBar(0, 2000);
private JLabel statusLabel = new JLabel("", SwingConstants.CENTER);
public FlashScreenPanel() {
setPreferredSize(new Dimension(800, 400));
statusLabel.setForeground(Color.CYAN);
statusLabel.setFont(new Font("Tahoma", Font.BOLD | Font.ITALIC, 18));
jb.setStringPainted(true);
JPanel bottomPanel = new JPanel(new BorderLayout(20, 20));
bottomPanel.add(jb, BorderLayout.PAGE_START);
bottomPanel.add(statusLabel, BorderLayout.CENTER);
int eb = 40;
setBorder(BorderFactory.createEmptyBorder(eb, eb, eb, eb));
setLayout(new GridLayout(0, 1));
add(new JLabel()); // dummy component to move prog bar lower
add(bottomPanel);
}
public void startProgress() {
statusLabel.setText(LOADING);
new Timer(TIMER_DELAY, new ActionListener() {
private int i = 0;
@Override
public void actionPerformed(ActionEvent e) {
i += 20;
jb.setValue(i);
if (i == 500) {
statusLabel.setText(PLEASE_WAIT);
} else
if (i == 1000) {
statusLabel.setText(LOADING_POLICE_STATION);
} else
if (i == 1200) {
statusLabel.setText(PLEASE_WAIT);
} else
if (i == 1600) {
statusLabel.setText(ALMOST_DONE);
} else
if (i == 1980) {
statusLabel.setText(DONE);
} else
if (i == 2000) {
((Timer) e.getSource()).stop();
Window win = SwingUtilities.getWindowAncestor(FlashScreenPanel.this);
win.dispose();
}
}
}).start();
}
}
class MainAppPanel extends JPanel {
public MainAppPanel() {
setPreferredSize(new Dimension(600, 400));
}
}