我使用以下代码来测试我的JFrame的绑定值：
Rectangle r1 = new Rectangle();
Rectangle r2 = new Rectangle();
r1 = this.getBounds();
this.setExtendedState(JFrame.MAXIMIZED_BOTH); //this == JFrame
r2 = this.getBounds();
首先，我认为r2的值（关于x，y，宽度和高度）会有所不同，因为帧会自动调整大小。但是，根据调试器，变量r1和r2似乎（几乎）相等。
为什么会这样？我应该怎么做才能获得最大化JFrame的新值？
import java.awt.Color;
import java.awt.Dimension;
import java.awt.EventQueue;
import java.awt.Graphics;
import java.awt.Insets;
import java.awt.List;
import java.awt.Rectangle;
import java.awt.Toolkit;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.IOException;
import javax.imageio.ImageIO;
import javax.swing.BorderFactory;
import javax.swing.ImageIcon;
import javax.swing.JButton;
import javax.swing.JFileChooser;
import javax.swing.JFrame;
import javax.swing.JOptionPane;
import javax.swing.JPanel;
import javax.swing.JTextField;
import javax.swing.border.Border;
import javax.swing.border.EmptyBorder;
public class NewGUI extends JFrame {
private JPanel contentPane;
private List list;
private JButton btnSelectAgent;
private JTextField textField;
private JButton btnBrowse;
private JButton btnPreviousStep2;
private JButton btnLoad;
private JButton btnPreviousStep3;
private JButton btnStart;
private File file = null;
ImageIcon icon = new ImageIcon("image.gif");
Border blackline = BorderFactory.createLineBorder(Color.black);
private JPanel firstStepPanel;
private JPanel secondStepPanel;
private JPanel thirdStepPanel;
/**
* Launch the application.
*/
public static void main(String[] args) {
EventQueue.invokeLater(new Runnable() {
public void run() {
try {
NewGUI frame = new NewGUI();
frame.setVisible(true);
} catch (Exception e) {
e.printStackTrace();
}
}
});
}
/**
* Create the frame.
*/
public NewGUI() {
super("GUI");
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
setBounds(100, 100, 681, 422);
contentPane = new JPanel();
contentPane.setForeground(Color.BLACK);
contentPane.setBorder(new EmptyBorder(5, 5, 5, 5));
setContentPane(contentPane);
setLocationRelativeTo(null); //centered location
contentPane.setLayout(null);
//test codes begin
Insets insets = this.getInsets();
Rectangle r = new Rectangle();
Dimension d = new Dimension();
r.x = 0;
r.y = 0;
r.width = 1280;
r.height = 1024;
r = this.getMaximizedBounds();
d = this.getMaximumSize();
Rectangle r1 = new Rectangle();
Rectangle r2 = new Rectangle();
Dimension d1 = new Dimension();
Dimension d2 = new Dimension();
d1 = this.getSize();
r1 = this.getBounds();
this.setExtendedState(JFrame.MAXIMIZED_BOTH);
r = this.getMaximizedBounds();
r2 = r1;
this.setMaximizedBounds(r);
r2.width = this.getWidth();
r2.height = this.getHeight();
d2 = this.getSize();
//test codes end
/* pane.setLayout(null);
JButton b1 = new JButton("one");
JButton b2 = new JButton("two");
JButton b3 = new JButton("three");
pane.add(b1);
pane.add(b2);
pane.add(b3);
JPanel pane = new JPanel();
Insets insets = this.getInsets();
Rectangle r = new Rectangle();
r.x = insets.left;
r.y = insets.top;
JFrame frame = new JFrame();
frame.getInsets();
Dimension size = b1.getPreferredSize();
b1.setBounds(25 + insets.left, 5 + insets.top, size.width, size.height);
Rectangle r = new Rectangle();
r.x = 1;
r.y = 2;
b1.setBounds
size = b2.getPreferredSize();
b2.setBounds(55 + insets.left, 40 + insets.top, size.width, size.height);
size = b3.getPreferredSize();
b3.setBounds(150 + insets.left, 15 + insets.top, size.width + 50, size.height + 20);
...//In the main method:
Insets insets = frame.getInsets();
frame.setSize(300 + insets.left + insets.right, 125 + insets.top + insets.bottom);
*/
firstStepPanel = new JPanel();
firstStepPanel.setBounds(10, 10, 194, 363);
contentPane.add(firstStepPanel);
//this.add(firstStepPanel, BorderLayout.WEST);
firstStepPanel.setLayout(null);
firstStepPanel.setBorder(
BorderFactory.createTitledBorder(blackline, "Agent selection"));
//makeFrameFullSize(contentPane); //aparentemente nao funcionando
list = new List();
list.setBounds(10, 31, 169, 203);
firstStepPanel.add(list);
list.setMultipleSelections(true);
btnSelectAgent = new JButton("Select Agent");
btnSelectAgent.setBounds(10, 274, 169, 34);
firstStepPanel.add(btnSelectAgent);
secondStepPanel = new JPanel();
secondStepPanel.setBorder(
BorderFactory.createTitledBorder(blackline, "file selection"));
secondStepPanel.setBounds(214, 11, 266, 362);
contentPane.add(secondStepPanel);
//this.add(secondStepPanel, BorderLayout.CENTER);
secondStepPanel.setLayout(null);
btnLoad = new JButton("Load");
btnLoad.setBounds(78, 317, 118, 34);
secondStepPanel.add(btnLoad);
btnLoad.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent arg0) {
if (file == null) {
showMessage("Please, select a file on the upper options");
} else {
disableSecondStep();
enableThirdStep();
}
}
});
btnLoad.setEnabled(false);
textField = new JTextField();
textField.setBounds(10, 29, 157, 34);
secondStepPanel.add(textField);
textField.setEnabled(false);
textField.setColumns(10);
textField.setText("P:\\\\");
btnBrowse = new JButton("Browse");
btnBrowse.setBounds(167, 29, 89, 35);
secondStepPanel.add(btnBrowse);
btnBrowse.setEnabled(false);
btnPreviousStep2 = new JButton("<< Previous");
btnPreviousStep2.setBounds(78, 272, 118, 34);
secondStepPanel.add(btnPreviousStep2);
btnPreviousStep2.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
enableFirstStep();
disableSecondStep();
}
});
btnPreviousStep2.setEnabled(false);
thirdStepPanel = new JPanel();
thirdStepPanel.setBorder(
BorderFactory.createTitledBorder(blackline, "Process initialization"));
thirdStepPanel.setBounds(490, 10, 165, 362);
contentPane.add(thirdStepPanel);
//this.add(thirdStepPanel, BorderLayout.EAST);
thirdStepPanel.setLayout(null);
//thirdStepPanel.setSize(100, r.height);
//r.x += 100;
//thirdStepPanel.setBounds(r);
//thirdStepPanel.setBounds(r.x,r.y, r.width, r.height);
//thirdStepPanel.setAlignmentX(r.x);
//thirdStepPanel.setAlignmentY(r.y);
btnPreviousStep3 = new JButton("<< Previous");
btnPreviousStep3.setBounds(7, 56, 151, 34);
thirdStepPanel.add(btnPreviousStep3);
btnPreviousStep3.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
enableSecondStep();
disableThirdStep();
}
});
btnPreviousStep3.setEnabled(false);
btnStart = new JButton(icon);
btnStart.setBounds(7, 101, 151, 159);
thirdStepPanel.add(btnStart);
btnStart.setEnabled(false);
btnStart.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
showMessage("Process started!");
}
});
//btnStart.setBackground(Color.RED);
btnStart.setForeground(Color.BLACK);
btnStart.setOpaque(false);
btnStart.setBorderPainted(false);
btnStart.setContentAreaFilled(false);
btnBrowse.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
JFileChooser fc = new JFileChooser("some folder blablabla");
int returnVal = fc.showOpenDialog(null);
if (returnVal == JFileChooser.APPROVE_OPTION) {
file = fc.getSelectedFile();
//System.out.println(file.getPath());
textField.setText(file.getPath());
} else if (returnVal == JFileChooser.CANCEL_OPTION) {
//System.out.println("File dialog cancelled");
} else if (returnVal == JFileChooser.ERROR_OPTION) {
showMessage("Error in the file dialog!");
}
}
});
btnSelectAgent.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent arg0) {
if (list.getSelectedItems().length == 0) {
showMessage("Please, select an Agent in the Agent's list");
} else {
disableFirstStep();
enableSecondStep();
}
}
});
list.add("Zemax");
list.add("Roundspot");
list.add("CCDCamera");
list.add("HexapodXYTable");
/* this.setExtendedState(JFrame.MAXIMIZED_BOTH);
this.add(firstStepPanel, BorderLayout.WEST);
this.add(secondStepPanel, BorderLayout.CENTER);
this.add(thirdStepPanel, BorderLayout.EAST);*/
}
private void showMessage(String msg) {
JOptionPane.showMessageDialog(this, msg);
}
private void enableFirstStep() {
list.setEnabled(true);
btnSelectAgent.setEnabled(true);
}
private void enableSecondStep() {
textField.setEnabled(true);
btnBrowse.setEnabled(true);
btnPreviousStep2.setEnabled(true);
btnLoad.setEnabled(true);
}
private void enableThirdStep() {
btnPreviousStep3.setEnabled(true);
btnStart.setEnabled(true);
}
private void disableFirstStep() {
list.setEnabled(false);
btnSelectAgent.setEnabled(false);
}
private void disableSecondStep() {
textField.setEnabled(false);
btnBrowse.setEnabled(false);
btnPreviousStep2.setEnabled(false);
btnLoad.setEnabled(false);
}
private void disableThirdStep() {
btnPreviousStep3.setEnabled(false);
btnStart.setEnabled(false);
}
private void makeFrameFullSize(JPanel panel) {
Dimension screenSize = Toolkit.getDefaultToolkit().getScreenSize();
panel.setSize(screenSize.width, screenSize.height);
}
BufferedImage image;
public void nextButton() {
try {
image = ImageIO.read(new File("C:\\Users\\BAYGONCALVE\\Desktop\\red_button.png"));
} catch (IOException e) {
e.printStackTrace();
}
}
protected void paintComponent(Graphics g) {
super.paintComponents(g);
g.drawImage(image, 0, 0, null);
}
public Dimension getPreferredSize() {
return new Dimension(image.getWidth(), image.getHeight());
}
}
答案 0 :(得分：1)
主要问题是，框架实际上是不可见的。
例如，在我清理了你的代码后，我得到了......
r1 = java.awt.Rectangle[x=1280,y=820,width=0,height=0]
r2 = java.awt.Rectangle[x=1280,y=820,width=0,height=0]
d1 = java.awt.Dimension[width=0,height=0]
d2 = java.awt.Dimension[width=0,height=0]
（取消了对setBounds的呼吁以及其他一些事情）。基于窗口尚未实现的事实（未示出），对于我来说，尺寸实际上没有变化并不奇怪，因为直到你显示窗口，它没有将显示GraphicsDevice的上下文，因此无法确定实际最大大小...
如果你在构造函数中调用setVisible(true)，那么在调用setExtendedState(JFrame.MAXIMIZED_BOTH)之前我会...
r1 = java.awt.Rectangle[x=1214,y=801,width=132,height=38]
r2 = java.awt.Rectangle[x=-8,y=32,width=2576,height=1576]
d1 = java.awt.Dimension[width=132,height=38]
d2 = java.awt.Dimension[width=2576,height=1576]
旁注......
null布局。像素完美布局是现代UI设计中的一种幻觉，您无法控制字体，DPI，渲染管道或其他因素，这些因素将改变组件在屏幕上呈现的方式。 Swing旨在与布局管理器一起克服这些问题。如果你坚持忽略这些功能并违背API设计，那就要为很多头痛做好准备，永远不要过时努力...... java.awt.List尝试使用javax.swing.JList代替答案 1 :(得分：0)
试试这个
frame.getWidth() and frame.getHeight()
获取没有标题和其他边框的JFrame的大小
frame.getContentPane().getSize();