我正在使用Java swing GUI在NetBeans中创建显示面板。我需要在此GUI的JPanel上绘制图形。为了绘制图形，我创建了一个单独的类GraphPanel。
package softwaredevelopmentgroupproject;
import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.Rectangle;
import javax.swing.JFrame;
import javax.swing.JPanel;
public class GraphPanel extends JPanel
{
private int[] graphSource;
public GraphPanel()
{
graphSource = new int[] {2, 4, 9, 8, 13, 3, 8};
//setUpPanel();
}
public void setUpPanel()
{
this.setBackground(Color.LIGHT_GRAY);
}
@Override
protected void paintComponent(Graphics currentGraphics)
{
super.paintComponent(currentGraphics);
Graphics2D mainGraphics = (Graphics2D) currentGraphics;
for(int i = 0; i < graphSource.length; i++)
{
int height = this.getHeight()/graphSource.length;
int width = graphSource[i];
int xPosition = 0;
int yPosition = height * i;
int red = (int)(Math.random() * 256);
int green = (int)(Math.random() * 256);
int blue = (int)(Math.random() * 256);
int alpha = (int)(Math.random() * 255);
mainGraphics.setColor(new Color(red, green, blue, alpha));
mainGraphics.fill(new Rectangle(xPosition, yPosition, width, height));
}
}
}
问题是，如果我在GraphPanel类中包含以下代码，则只能在单独的JFrame中显示此图。
public static void main(String[] args)
{
JFrame jp1 = new JFrame();
GraphPanel graph = new GraphPanel();
jp1.add(graph, BorderLayout.CENTER);
jp1.setSize(new Dimension(200,200));
jp1.setVisible(true);
}
这是我的Swing GUI的代码。
package softwaredevelopmentgroupproject;
import java.awt.Dimension;
import java.awt.FlowLayout;
import java.awt.Graphics;
import java.util.ArrayList;
import javax.swing.JFrame;
import javax.swing.JOptionPane;
import javax.swing.table.DefaultTableModel;
public class AppGUI extends javax.swing.JFrame {
public AppGUI()
{
initComponents();
displayProperties();
//displayBarChart();
}
public ArrayList<String> getProperties()
{
ArrayList<String> propertiesList = new ArrayList<>();
try
{
String propertyName = "3 bedroom house overlooking seafront";
String propertyAddress = "139 Archard Street, N69 7GG";
double price = 957.90;
String displayPrice = "£" + price + " per month";
String value = propertyName + System.lineSeparator() + propertyAddress + System.lineSeparator() + displayPrice + System.lineSeparator();
propertiesList.add(propertyName);
propertiesList.add(propertyAddress);
propertiesList.add(displayPrice);
}
catch(Exception e)
{
JOptionPane.showMessageDialog(null, e);
}
return propertiesList;
}
public void displayProperties()
{
ArrayList<String> list = getProperties();
//propertyListings.setModel(new PropertyTableModel(td, col));
DefaultTableModel model = (DefaultTableModel) propertyListings.getModel();
//propertyListings.setDefaultRenderer(AppGUI.class, model);
//propertyListings.getColumnModel().getColumn(0).setCellRenderer(model);
Object[] row = new Object[1]; //list.size()
for(int i = 0; i < list.size(); i++)
{
row[0] = list.get(i);
model.addRow(row);
}
}
public void displayBarChart()
{
GraphPanel graph = new GraphPanel();
Graphics graphics = graph.getGraphics();
graphPanel.paint(graphics);
graphPanel.repaint();
//graphPanel.add(graph, FlowLayout.CENTER);
//graphPanel.setSize(new Dimension(200,200));
//graphPanel.setVisible(true);
}
@SuppressWarnings("unchecked")
// <editor-fold defaultstate="collapsed" desc="Generated Code">
private void initComponents() {
jScrollPane1 = new javax.swing.JScrollPane();
jTable1 = new javax.swing.JTable();
topPanel = new javax.swing.JPanel();
dateTimeDisplay = new javax.swing.JLabel();
welcomeMessage = new javax.swing.JLabel();
searchPanel = new javax.swing.JPanel();
enterPrice1 = new javax.swing.JTextField();
toLabel = new javax.swing.JLabel();
enterPrice2 = new javax.swing.JTextField();
searchPropertiesButton = new javax.swing.JButton();
jPanel3 = new javax.swing.JPanel();
jScrollPane2 = new javax.swing.JScrollPane();
propertyListings = new javax.swing.JTable();
graphPanel = new java.awt.Panel();
jTable1.setModel(new javax.swing.table.DefaultTableModel(
new Object [][] {
{null, null, null, null},
{null, null, null, null},
{null, null, null, null},
{null, null, null, null}
},
new String [] {
"Title 1", "Title 2", "Title 3", "Title 4"
}
));
jScrollPane1.setViewportView(jTable1);
setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE);
topPanel.setBackground(new java.awt.Color(67, 38, 126));
topPanel.setBorder(new javax.swing.border.SoftBevelBorder(javax.swing.border.BevelBorder.RAISED));
dateTimeDisplay.setText("Date/Time");
welcomeMessage.setText("Welcome back, blah");
javax.swing.GroupLayout topPanelLayout = new javax.swing.GroupLayout(topPanel);
topPanel.setLayout(topPanelLayout);
topPanelLayout.setHorizontalGroup(
topPanelLayout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addGroup(topPanelLayout.createSequentialGroup()
.addGap(65, 65, 65)
.addComponent(dateTimeDisplay)
.addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED, javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE)
.addComponent(welcomeMessage)
.addGap(182, 182, 182))
);
topPanelLayout.setVerticalGroup(
topPanelLayout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addGroup(topPanelLayout.createSequentialGroup()
.addGap(8, 8, 8)
.addGroup(topPanelLayout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE)
.addComponent(dateTimeDisplay)
.addComponent(welcomeMessage))
.addGap(0, 16, Short.MAX_VALUE))
);
enterPrice1.addActionListener(new java.awt.event.ActionListener() {
public void actionPerformed(java.awt.event.ActionEvent evt) {
enterPrice1ActionPerformed(evt);
}
});
toLabel.setText("to");
enterPrice2.addActionListener(new java.awt.event.ActionListener() {
public void actionPerformed(java.awt.event.ActionEvent evt) {
enterPrice2ActionPerformed(evt);
}
});
searchPropertiesButton.setBackground(new java.awt.Color(67, 38, 126));
searchPropertiesButton.setText("Search for a property");
searchPropertiesButton.addActionListener(new java.awt.event.ActionListener() {
public void actionPerformed(java.awt.event.ActionEvent evt) {
searchPropertiesButtonActionPerformed(evt);
}
});
javax.swing.GroupLayout searchPanelLayout = new javax.swing.GroupLayout(searchPanel);
searchPanel.setLayout(searchPanelLayout);
searchPanelLayout.setHorizontalGroup(
searchPanelLayout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addGroup(searchPanelLayout.createSequentialGroup()
.addGap(28, 28, 28)
.addComponent(enterPrice1, javax.swing.GroupLayout.PREFERRED_SIZE, 77, javax.swing.GroupLayout.PREFERRED_SIZE)
.addGap(18, 18, 18)
.addComponent(toLabel)
.addGap(18, 18, 18)
.addComponent(enterPrice2, javax.swing.GroupLayout.PREFERRED_SIZE, 79, javax.swing.GroupLayout.PREFERRED_SIZE)
.addGap(47, 47, 47)
.addComponent(searchPropertiesButton)
.addContainerGap(javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE))
);
searchPanelLayout.setVerticalGroup(
searchPanelLayout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addGroup(searchPanelLayout.createSequentialGroup()
.addGap(30, 30, 30)
.addGroup(searchPanelLayout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE)
.addComponent(enterPrice1, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE)
.addComponent(toLabel)
.addComponent(enterPrice2, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE)
.addComponent(searchPropertiesButton))
.addContainerGap(javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE))
);
javax.swing.GroupLayout jPanel3Layout = new javax.swing.GroupLayout(jPanel3);
jPanel3.setLayout(jPanel3Layout);
jPanel3Layout.setHorizontalGroup(
jPanel3Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addGap(0, 467, Short.MAX_VALUE)
);
jPanel3Layout.setVerticalGroup(
jPanel3Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addGap(0, 7, Short.MAX_VALUE)
);
propertyListings.setModel(new javax.swing.table.DefaultTableModel(
new Object [][] {
},
new String [] {
"Property Listings in Oslo"
}
));
jScrollPane2.setViewportView(propertyListings);
graphPanel.addContainerListener(new java.awt.event.ContainerAdapter() {
public void componentAdded(java.awt.event.ContainerEvent evt) {
graphPanelComponentAdded(evt);
}
});
graphPanel.addComponentListener(new java.awt.event.ComponentAdapter() {
public void componentShown(java.awt.event.ComponentEvent evt) {
graphPanelComponentShown(evt);
}
});
javax.swing.GroupLayout layout = new javax.swing.GroupLayout(getContentPane());
getContentPane().setLayout(layout);
layout.setHorizontalGroup(
layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addComponent(topPanel, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE)
.addComponent(searchPanel, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE)
.addGroup(layout.createSequentialGroup()
.addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addGroup(layout.createSequentialGroup()
.addComponent(jPanel3, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE)
.addGap(0, 0, Short.MAX_VALUE))
.addGroup(javax.swing.GroupLayout.Alignment.TRAILING, layout.createSequentialGroup()
.addGap(0, 0, Short.MAX_VALUE)
.addComponent(jScrollPane2, javax.swing.GroupLayout.PREFERRED_SIZE, 444, javax.swing.GroupLayout.PREFERRED_SIZE)))
.addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
.addComponent(graphPanel, javax.swing.GroupLayout.PREFERRED_SIZE, 410, javax.swing.GroupLayout.PREFERRED_SIZE)
.addGap(38, 38, 38))
);
layout.setVerticalGroup(
layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addGroup(layout.createSequentialGroup()
.addComponent(topPanel, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE)
.addGap(1, 1, 1)
.addComponent(searchPanel, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE)
.addGap(36, 36, 36)
.addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING, false)
.addComponent(graphPanel, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE)
.addComponent(jScrollPane2, javax.swing.GroupLayout.DEFAULT_SIZE, 391, Short.MAX_VALUE))
.addGap(28, 28, 28)
.addComponent(jPanel3, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE))
);
pack();
}// </editor-fold>
private void enterPrice1ActionPerformed(java.awt.event.ActionEvent evt) {
// TODO add your handling code here:
}
private void searchPropertiesButtonActionPerformed(java.awt.event.ActionEvent evt) {
// TODO add your handling code here:
}
private void enterPrice2ActionPerformed(java.awt.event.ActionEvent evt) {
// TODO add your handling code here:
}
private void graphPanelComponentShown(java.awt.event.ComponentEvent evt) {
}
private void graphPanelComponentAdded(java.awt.event.ContainerEvent evt) {
// TODO add your handling code here:
}
public static void main(String args[])
{
/* Set the Nimbus look and feel */
//<editor-fold defaultstate="collapsed" desc=" Look and feel setting code (optional) ">
/* If Nimbus (introduced in Java SE 6) is not available, stay with the default look and feel.
* For details see http://download.oracle.com/javase/tutorial/uiswing/lookandfeel/plaf.html
*/
try {
for (javax.swing.UIManager.LookAndFeelInfo info : javax.swing.UIManager.getInstalledLookAndFeels()) {
if ("Nimbus".equals(info.getName())) {
javax.swing.UIManager.setLookAndFeel(info.getClassName());
break;
}
}
} catch (ClassNotFoundException ex) {
java.util.logging.Logger.getLogger(AppGUI.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
} catch (InstantiationException ex) {
java.util.logging.Logger.getLogger(AppGUI.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
} catch (IllegalAccessException ex) {
java.util.logging.Logger.getLogger(AppGUI.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
} catch (javax.swing.UnsupportedLookAndFeelException ex) {
java.util.logging.Logger.getLogger(AppGUI.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
}
//</editor-fold>
/* Create and display the form */
java.awt.EventQueue.invokeLater(new Runnable()
{
public void run()
{
new AppGUI().setVisible(true);
}
});
}
// Variables declaration - do not modify
private javax.swing.JLabel dateTimeDisplay;
private javax.swing.JTextField enterPrice1;
private javax.swing.JTextField enterPrice2;
public java.awt.Panel graphPanel;
private javax.swing.JPanel jPanel3;
private javax.swing.JScrollPane jScrollPane1;
private javax.swing.JScrollPane jScrollPane2;
private javax.swing.JTable jTable1;
private javax.swing.JTable propertyListings;
private javax.swing.JPanel searchPanel;
private javax.swing.JButton searchPropertiesButton;
private javax.swing.JLabel toLabel;
private javax.swing.JPanel topPanel;
private javax.swing.JLabel welcomeMessage;
// End of variables declaration
}
由于我正在测试不同的方法来显示图形，因此代码相当混乱，因此希望它是可读的。我的displayBarChart方法是我试图在GUI中显示它，但是由于某种原因它根本不会显示。
最佳答案
GraphPanel是JPanel，可以像其他任何组件一样添加。
做一些小的改动：
将public java.awt.Panel graphPanel;更改为public javax.swing.JPanel graphPanel;-没有理由使用AWT组件。使用Swing JPanel。
将graphPanel = new java.awt.Panel();更改为graphPanel = new GraphPanel();-您不想构造空白面板。您要构造一个GraphPanel
删除displayBarChart()方法-不再使用。
这样就完成了：