请务必观看代码示例，请务必仔细观看所有内容，添加内容的顺序JFrame。由于在您的示例中，您在将setSize()某些内容添加到之前调用了很多JFrame，因此首先将组件添加到容器中，然后调用它的pack()/setSize()方法，以便它可以很好地实现这一点。
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
public class PizzaLayout
{
/*
* Five JPanels we will be using.
*/
private JPanel headerPanel;
private JPanel footerPanel;
// This JPanel will contain the middle components.
private JPanel centerPanel;
private JPanel toppingPanel;
private JPanel sizePanel;
private JPanel typePanel;
private JPanel buttonPanel;
private String[] toppings = {
"Tomato",
"Green Pepper",
"Black Olives",
"Mushrooms",
"Extra Cheese",
"Pepproni",
"Sausage"
};
private JCheckBox[] toppingsCBox;
private String[] sizePizza = {
"Small $6.50",
"Medium $8.50",
"Large $10.00"
};
private JRadioButton[] sizePizzaRButton;
private String[] typePizza = {
"Thin Crust",
"Medium Crust",
"Pan"
};
private JRadioButton[] typePizzaRButton;
private JButton processButton;
private ButtonGroup bGroupType, bGroupSize;
private JTextArea orderTArea;
private StringBuilder sBuilderOrder;
private void displayGUI()
{
JFrame frame = new JFrame("Pizza Shop");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
/*
* This JPanel is the base of all the
* other components, and at the end
* we will set this as Content Pane
* for the JFrame.
*/
JPanel contentPane = new JPanel();
contentPane.setLayout(new BorderLayout(5, 5));
contentPane.setBorder(
BorderFactory.createEmptyBorder(10, 10, 10, 10));
/*
* TOP PART of the LAYOUT.
*/
headerPanel = new JPanel();
JLabel headerLabel = new JLabel(
"Welcome to Home Style Pizza Shop"
, JLabel.CENTER);
headerLabel.setForeground(Color.RED);
headerPanel.add(headerLabel);
/*
* CENTER PART of the LAYOUT.
*/
centerPanel = new JPanel();
centerPanel.setLayout(new GridBagLayout());
GridBagConstraints gbc = new GridBagConstraints();
gbc.anchor = GridBagConstraints.FIRST_LINE_START;
gbc.fill = GridBagConstraints.BOTH;
gbc.gridx = 0;
gbc.gridy = 0;
gbc.gridheight = 2;
gbc.weightx = 0.3;
gbc.weighty = 1.0;
/*
* Above Constraints are for this part.
*/
toppingPanel = new JPanel();
toppingPanel.setBorder(
BorderFactory.createTitledBorder(
BorderFactory.createLineBorder(Color.RED),
"Each Topping $1.50"));
JPanel checkBoxesPanel = new JPanel();
checkBoxesPanel.setBorder(
BorderFactory.createEmptyBorder(5, 5, 5, 5));
checkBoxesPanel.setLayout(new GridLayout(0, 1, 5, 5));
toppingsCBox = new JCheckBox[toppings.length];
for (int i = 0; i < toppings.length; i++)
{
toppingsCBox[i] = new JCheckBox(toppings[i]);
checkBoxesPanel.add(toppingsCBox[i]);
}
toppingPanel.add(checkBoxesPanel);
centerPanel.add(toppingPanel, gbc);
// Till this.
gbc.gridx = 1;
gbc.gridheight = 1;
gbc.weighty = 0.7;
/*
* Above Constraints are for this part.
*/
sizePanel = new JPanel();
sizePanel.setBorder(
BorderFactory.createTitledBorder(
BorderFactory.createLineBorder(Color.RED),
"Pizza Size"));
JPanel radioBoxesPanel = new JPanel();
radioBoxesPanel.setBorder(
BorderFactory.createEmptyBorder(5, 5, 5, 5));
radioBoxesPanel.setLayout(new GridLayout(0, 1, 10, 10));
sizePizzaRButton = new JRadioButton[sizePizza.length];
bGroupSize = new ButtonGroup();
for (int i = 0; i < sizePizza.length; i++)
{
sizePizzaRButton[i] = new JRadioButton(sizePizza[i]);
bGroupSize.add(sizePizzaRButton[i]);
radioBoxesPanel.add(sizePizzaRButton[i]);
}
sizePanel.add(radioBoxesPanel);
centerPanel.add(sizePanel, gbc);
// Till this.
gbc.gridx = 2;
gbc.weighty = 0.7;
/*
* Above Constraints are for this part.
*/
typePanel = new JPanel();
typePanel.setBorder(
BorderFactory.createTitledBorder(
BorderFactory.createLineBorder(Color.RED),
"Pizza Type"));
JPanel radioBoxesTypePanel = new JPanel();
radioBoxesTypePanel.setBorder(
BorderFactory.createEmptyBorder(5, 5, 5, 5));
radioBoxesTypePanel.setLayout(new GridLayout(0, 1, 10, 10));
typePizzaRButton = new JRadioButton[typePizza.length];
bGroupType = new ButtonGroup();
for (int i = 0; i < typePizza.length; i++)
{
typePizzaRButton[i] = new JRadioButton(typePizza[i]);
bGroupType.add(typePizzaRButton[i]);
radioBoxesTypePanel.add(typePizzaRButton[i]);
}
typePanel.add(radioBoxesTypePanel);
centerPanel.add(typePanel, gbc);
// Till this.
gbc.gridx = 1;
gbc.gridy = 1;
gbc.weighty = 0.3;
gbc.gridwidth = 2;
processButton = new JButton("Process Selection");
processButton.addActionListener(
new ActionListener()
{
@Override
public void actionPerformed(ActionEvent ae)
{
sBuilderOrder = new StringBuilder();
sBuilderOrder.append("Pizza type : ");
for (int i = 0; i < typePizza.length; i++)
{
if (typePizzaRButton[i].isSelected())
sBuilderOrder.append(typePizzaRButton[i].getText());
}
sBuilderOrder.append("\n");
sBuilderOrder.append("Pizza Size : ");
for (int i = 0; i < sizePizza.length; i++)
{
if (sizePizzaRButton[i].isSelected())
sBuilderOrder.append(sizePizzaRButton[i].getText());
}
sBuilderOrder.append("\n");
sBuilderOrder.append("Toppings : ");
/*
* I hope you can do this part yourself now :-)
*/
orderTArea.setText(sBuilderOrder.toString());
}
});
centerPanel.add(processButton, gbc);
footerPanel = new JPanel();
footerPanel.setLayout(new BorderLayout(5, 5));
footerPanel.setBorder(
BorderFactory.createTitledBorder("Your Order : "));
orderTArea = new JTextArea(10, 10);
footerPanel.add(orderTArea, BorderLayout.CENTER);
contentPane.add(headerPanel, BorderLayout.PAGE_START);
contentPane.add(centerPanel, BorderLayout.CENTER);
contentPane.add(footerPanel, BorderLayout.PAGE_END);
frame.setContentPane(contentPane);
frame.pack();
frame.setLocationByPlatform(true);
frame.setVisible(true);
}
public static void main(String[] args)
{
EventQueue.invokeLater(new Runnable()
{
@Override
public void run()
{
new PizzaLayout().displayGUI();
}
});
}
}
这是相同的输出：
