我正在开发一个使用JLabel显示信息的航班信息显示（FID）应用程序。我有不同的JPanels包含不同的标签。
我的问题是，当我启动窗口时，它会正确显示每个组件保持其所需的布局位置，但是当您尝试在最小化后恢复窗口时标签位置会发生变化（中心处的簇）。从而将所有标签聚集在一起。我真的需要解决这个问题。
以下是我的代码片段：
import java.awt.Color;
import java.awt.Dimension;
import java.awt.EventQueue;
import java.awt.Font;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.Insets;
import java.awt.Toolkit;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.text.SimpleDateFormat;
import java.util.Calendar;
import java.util.Date;
import java.util.TimeZone;
import javax.swing.ImageIcon;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.Timer;
public class Departure extends javax.swing.JFrame {
final private JPanel container = new JPanel();
final private JPanel secPanel;
final private JPanel imgPanel;
final private JLabel logo;
final private JLabel lagosLbl;
final private JLabel londonLbl;
final private JLabel newYorkLbl;
final private JLabel lagosTime;
final private JLabel londonTime;
final private JLabel newYorkTime;
final private JLabel departureLbl;
final private JLabel airlineHd;
final private JLabel flightHd;
final private JLabel destHd;
final private JLabel schedHd;
final private JLabel gateHd;
final private JLabel statusHd;
final private JLabel footer;
private JLabel footerLeft, footerMid, footerRight;
private String todayDate, timeLocale, timeLondon, timeNewYork;
Dimension sizeMain, sizeHeading, sizeBody, sizeLogo, sizeSec, screenSize;
Insets insetsMain, insetsHeading, insetsBody, insetsLogo, insetsSec;
public Departure(){
super("DEPARTURES");
screenSize = Toolkit.getDefaultToolkit().getScreenSize();
setBounds(0,0,screenSize.width, screenSize.height);
this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
this.setLocationRelativeTo(null);
this.setResizable(false);
this.setVisible(true);
container.setPreferredSize(new Dimension(screenSize.width,
screenSize.height));
container.setBackground(new Color(53,86,163));
this.getContentPane().add(container);
Insets insets = this.getInsets();
Dimension size = container.getPreferredSize();
container.setBounds(0 + insets.left, 0 + insets.top,
size.width + 5, size.height + 5);
container.setLayout(null);
ImageIcon icon = new ImageIcon(getClass().getResource("headerDe.jpg"));
logo = new JLabel();
logo.setIcon(new
ImageIcon(icon.getImage().getScaledInstance(screenSize.width, 200,
java.awt.Image.SCALE_SMOOTH)));
logo.setBackground(new Color(0,0,0));
container.add(logo);
insetsMain = container.getInsets();
sizeMain = logo.getPreferredSize();
logo.setBounds(0 + insetsMain.left, 0 + insetsMain.top,
sizeMain.width + 5, sizeMain.height + 5);
lagosLbl = new JLabel("LAGOS:");
lagosLbl.setFont(new Font("Century Gothic",Font.BOLD, 40));
lagosLbl.setForeground(new Color(0,0,140));
logo.add(lagosLbl);
insetsLogo = logo.getInsets();
sizeLogo = lagosLbl.getPreferredSize();
lagosLbl.setBounds(1550 + insetsLogo.left, 5 + insetsLogo.top,
sizeLogo.width + 5, sizeLogo.height + 5);
timeLocale = myTimeLocale();
lagosTime = new JLabel(timeLocale);
lagosTime.setFont(new Font("Century Gothic",Font.BOLD, 45));
lagosTime.setForeground(new Color(0,0,140));
logo.add(lagosTime);
sizeLogo = lagosTime.getPreferredSize();
lagosTime.setBounds(1750 + insetsLogo.left, 2 + insetsLogo.top,
sizeLogo.width + 5, sizeLogo.height + 5);
londonLbl = new JLabel("LONDON:");
londonLbl.setFont(new Font("Century Gothic",Font.BOLD, 40));
londonLbl.setForeground(new Color(0,0,140));
logo.add(londonLbl);
sizeLogo = londonLbl.getPreferredSize();
londonLbl.setBounds(1515 + insetsLogo.left, 65 + insetsLogo.top,
sizeLogo.width + 5, sizeLogo.height + 5);
timeLondon = myTimeLondon();
londonTime = new JLabel(timeLondon);
londonTime.setFont(new Font("Century Gothic",Font.BOLD, 45));
londonTime.setForeground(new Color(0,0,140));
logo.add(londonTime);
sizeLogo = londonTime.getPreferredSize();
londonTime.setBounds(1750 + insetsLogo.left, 62 + insetsLogo.top,
sizeLogo.width + 5, sizeLogo.height + 5);
newYorkLbl = new JLabel("NEW YORK:");
newYorkLbl.setFont(new Font("Century Gothic",Font.BOLD, 40));
newYorkLbl.setForeground(new Color(0,0,140));
logo.add(newYorkLbl);
sizeLogo = newYorkLbl.getPreferredSize();
newYorkLbl.setBounds(1485 + insetsLogo.left, 125 + insetsLogo.top,
sizeLogo.width + 5, sizeLogo.height + 5);
timeNewYork = myTimeNewYork();
newYorkTime = new JLabel(timeNewYork);
newYorkTime.setFont(new Font("Century Gothic",Font.BOLD, 45));
newYorkTime.setForeground(new Color(0,0,140));
myTimeNewYork();
logo.add(newYorkTime);
sizeLogo = newYorkTime.getPreferredSize();
newYorkTime.setBounds(1750 + insetsLogo.left, 122 + insetsLogo.top,
sizeLogo.width + 5, sizeLogo.height + 5);
departureLbl = new JLabel("DEPARTURES");
departureLbl.setFont(new Font("Century Gothic",Font.BOLD, 100));
departureLbl.setForeground(new Color(53,86,163));
logo.add(departureLbl);
sizeLogo = departureLbl.getPreferredSize();
departureLbl.setBounds(680 + insetsLogo.left, 50 + insetsLogo.top,
sizeLogo.width + 5, sizeLogo.height + 5);
secPanel = new JPanel();
secPanel.setPreferredSize( new Dimension( screenSize.width,
(screenSize.width - 300) ) );
secPanel.setBackground(new Color(255,255,255));
container.add(secPanel);
sizeMain = secPanel.getPreferredSize();
secPanel.setBounds(0 + insetsMain.left, 200 + insetsMain.top,
sizeMain.width + 5, sizeMain.height + 5);
imgPanel = new JPanel();
imgPanel.setPreferredSize( new Dimension( screenSize.width,45 ) );
imgPanel.setBackground(new Color(0,0,140));
secPanel.add(imgPanel);
insetsHeading = secPanel.getInsets();
sizeHeading = imgPanel.getPreferredSize();
imgPanel.setBounds(0 + insetsHeading.left, 5 + insetsHeading.top,
sizeHeading.width + 5, sizeHeading.height + 5);
schedHd = new JLabel("STD");
schedHd.setFont(new Font("Century Gothic",Font.BOLD, 28));
schedHd.setForeground(new Color(255, 255, 255));
imgPanel.add(schedHd);
insetsHeading = imgPanel.getInsets();
sizeHeading = schedHd.getPreferredSize();
schedHd.setBounds(100 + insetsHeading.left, 5 + insetsHeading.top,
sizeHeading.width + 5, sizeHeading.height + 5);
airlineHd = new JLabel("AIRLINE");
airlineHd.setFont(new Font("Century Gothic",Font.BOLD, 28));
airlineHd.setForeground(new Color(255, 255, 255));
imgPanel.add(airlineHd);
sizeHeading = airlineHd.getPreferredSize();
airlineHd.setBounds(350 + insetsHeading.left, 5 + insetsHeading.top,
sizeHeading.width + 5, sizeHeading.height + 5);
destHd = new JLabel("DESTINATION");
destHd.setFont(new Font("Century Gothic",Font.BOLD, 28));
destHd.setForeground(new Color(255, 255, 255));
imgPanel.add(destHd);
sizeHeading = destHd.getPreferredSize();
destHd.setBounds(650 + insetsHeading.left, 5 + insetsHeading.top,
sizeHeading.width + 5, sizeHeading.height + 5);
flightHd = new JLabel("FLIGHT");
flightHd.setFont(new Font("Century Gothic",Font.BOLD, 28));
flightHd.setForeground(new Color(255, 255, 255));
imgPanel.add(flightHd);
sizeHeading = flightHd.getPreferredSize();
flightHd.setBounds(1020 + insetsHeading.left, 5 + insetsHeading.top,
sizeHeading.width + 5, sizeHeading.height + 5);
gateHd = new JLabel("GATE");
gateHd.setFont(new Font("Century Gothic",Font.BOLD, 28));
gateHd.setForeground(new Color(255, 255, 255));
imgPanel.add(gateHd);
sizeHeading = gateHd.getPreferredSize();
gateHd.setBounds(1280 + insetsHeading.left, 5 + insetsHeading.top,
sizeHeading.width + 5, sizeHeading.height + 5);
statusHd = new JLabel("STATUS");
statusHd.setFont(new Font("Century Gothic",Font.BOLD, 28));
statusHd.setForeground(new Color(255, 255, 255));
imgPanel.add(statusHd);
sizeHeading = statusHd.getPreferredSize();
statusHd.setBounds(1520 + insetsHeading.left, 5 + insetsHeading.top,
sizeHeading.width + 5, sizeHeading.height + 5);
ImageIcon foot = new ImageIcon(getClass().getResource("footer.jpg"));
footer = new JLabel();
footer.setIcon(new
ImageIcon(foot.getImage().getScaledInstance(screenSize.width, 70,
java.awt.Image.SCALE_SMOOTH)));
secPanel.add(footer);
size = footer.getPreferredSize();
footer.setBounds(0 + insets.left, 760 + insets.top,
size.width + 5, size.height + 5);
todayDate = dayOfWeek() + " "+ myDate();
footerLeft = new JLabel(todayDate);
footerLeft.setFont(new Font("Century Gothic",Font.BOLD, 30));
footerLeft.setForeground(new Color(255,255,255));
footer.add(footerLeft);
size = footerLeft.getPreferredSize();
footerLeft.setBounds(15 + insets.left, 15 + insets.top,
size.width + 5, size.height + 5);
footerMid = new JLabel();
//footerMid.setPreferredSize(new Dimension(120, 70));
footerMid.setFont(new Font("Century Gothic",Font.BOLD, 30));
footerMid.setForeground(new Color(255,255,255));
footer.add(footerMid);
size = footerMid.getPreferredSize();
footerMid.setBounds(450 + insets.left, 15 + insets.top,
size.width + 5, size.height + 5);
footerRight = new JLabel();
footerRight.setFont(new Font("Century Gothic",Font.BOLD, 30));
footerRight.setForeground(new Color(255,255,255));
footer.add(footerRight);
size = footerRight.getPreferredSize();
footerRight.setBounds(1540 + insets.left, 15 + insets.top,
size.width + 5, size.height + 5);
}
public String dayOfWeek(){
Date now = new Date();
SimpleDateFormat simpleDateformat = new SimpleDateFormat("EEEE"); // the
day of the week in full
//SimpleDateFormat simpleDateformat = new SimpleDateFormat("E"); // the
day of the week abbreviated
return simpleDateformat.format(now);
}
protected static String myDate(){
Calendar myD = Calendar.getInstance();
SimpleDateFormat d = new SimpleDateFormat("dd/MM/yyyy");
String date = (d.format(myD.getTime()));
return date;
}
public static void main(String args []){
Departure departure = new Departure();
}
}
在GridLayout上使用imgPanel并使用循环添加标签。确保使用SwingConstants.CENTER将标签文本居中。
标签将全部等距离，您不需要设置任何插入或边距。
List<String> labels = Arrays.asList("STD", "AIRLINE", "DESTINATION", "FLIGHT", "GATE", "STATUS");
imgPanel.setLayout(new GridLayout(1, labels.size())); // 1 row, 6 columns
labels.stream().forEach(s -> {
JLabel label = new JLabel(s, SwingConstants.CENTER); // centered label text
label.setFont(new Font("Century Gothic", Font.BOLD, 28));
label.setForeground(new Color(255, 255, 255));
imgPanel.add(label);
});
您也可以在开始添加标签之前设置布局，但这更麻烦而且不动态。
imgPanel.setLayout(new GridLayout(1, 6)); // Six labels tiled horizontally
并且不要忘记将标签文本居中。
schedHd = new JLabel("STD", SwingConstants.CENTER);
airlineHd = new JLabel("AIRLINE", SwingConstants.CENTER);
// etc...
感谢所有回答我问题的人。我后来发现我没有明确定义我在向它们添加一些内容（标签）之前声明的每个容器（面板）的布局，因此当我恢复窗口时，维度往往会分散。虽然这可能很麻烦，但我确实喜欢绝对控制窗口中每个项目的位置。再次感谢
以下是我如何解决它的一个例子;
//After initializing the imgPanel
imgPanel.setLayout(null); //explicitly declare the imgPanel layout to null
JLabel lbl = new JLabel("STD");
imgPanel.add(lbl)
Insets imgPanelInsets = imgPanel.getInsets(); //define the components insets
Dimension sizeImg = lbl.getPreferredSize(); //define the components dimension
lbl.setBounds(100 + imgPanelInsets.left, 5 + imgPanelInsets.top,
sizeImg.width + 5, sizeImg.height + 5);
JLabel lbl2 = new JLabel("AIRLINE");
imgPanel.add(lbl2)
sizeImg = lbl2.getPreferredSize();
lbl2.setBounds(100 + imgPanelInsets.left, 5 + imgPanelInsets.top,
sizeImg.width + 5, sizeImg.height + 5);