ユーザーがファイルを選択してJPanelに表示できるようにするメニューバーを使用しようとしていますが、画像はJPanelに正確に収まる必要があります。しかし、JFileChooser は、ダイアログ ボックスからファイルを正常に選択しても何も表示しません。多くのリンクを参照してみました: JPanelに画像を追加するには? 画像ファイルを 参照し、Java Swing を使用して表示します が、何もうまくいきません。助けてください。以下は私のコードです:
import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
import java.io.File;
class Main {
private JFrame j;
private JMenu jmenu;
private JMenuBar jbar;
private JMenuItem jmi, jexit;
private JPanel jpanel, jpanelbar;
private JButton jpre, jnext;
JLabel image;
ImageIcon ic;
Image img;
Main() {
j = new JFrame("Image Viewer");
j.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
// j.setExtendedState(Frame.MAXIMIZED_BOTH);
// j.setLocationRelativeTo(null);
j.setLocationByPlatform(true);
j.setLayout(new GridBagLayout());
GridBagConstraints c = new GridBagConstraints();
jpanel = new JPanel();
c.anchor = GridBagConstraints.PAGE_START;
c.fill = GridBagConstraints.HORIZONTAL;
c.gridx = c.gridy = 0;
c.gridwidth = 2;
// c.weightx=0.1;
c.weighty = 0.1;
c.ipady = 600;
c.insets = new Insets(5, 5, 10, 5);
// jpanel.setBackground(Color.BLACK);
j.add(jpanel, c);
jpanelbar = new JPanel();
jpanelbar.setBackground(Color.red);
c.weightx = 0.1;
c.gridx = 0;
c.gridy = 1;
c.fill = GridBagConstraints.HORIZONTAL;
c.insets = new Insets(5, 5, 5, 5);
c.ipady = 150;
j.add(jpanelbar, c);
jpanelbar.setLayout(new GridBagLayout());
GridBagConstraints x = new GridBagConstraints();
jpre = new JButton("Previous");
x.gridx = 0;
x.gridy = 0;
x.gridwidth = 1;
x.weightx = 0.1;
// x.insets=new Insets(5,5,5,5);
// x.fill=GridBagConstraints.NONE;
jpanelbar.add(jpre, x);
jnext = new JButton("Next");
x.gridx = 1;
jpanelbar.add(jnext, x);
// Creating Menu
jbar = new JMenuBar();
jmenu = new JMenu("File");
jmi = new JMenuItem("Open");
jmi.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent ae) {
JFileChooser fc = new JFileChooser();
int result = fc.showOpenDialog(null);
if (result == JFileChooser.APPROVE_OPTION) {
File file = fc.getSelectedFile();
String sname = file.getName();
image = new JLabel("", new ImageIcon(sname), JLabel.CENTER);
jpanel.add(image, BorderLayout.CENTER);
}
}
});
jexit = new JMenuItem("Exit");
jexit.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent ae) {
System.exit(0);
}
});
jmenu.add(jmi);
jmenu.add(jexit);
jbar.add(jmenu);
j.setJMenuBar(jbar);
j.setSize(800, 600);
j.setResizable(false);
j.setVisible(true);
}
public static void main(String s[]) {
SwingUtilities.invokeLater(new Runnable() {
public void run() {
new Main();
}
});
}
}
更新されたコードは次のとおりです。
import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
import java.io.File;
class Main {
private JFrame j;
private JMenu jmenu;
private JMenuBar jbar;
private JMenuItem jmi, jexit;
private JPanel jpanel, jpanelbar;
private JButton jpre, jnext;
JLabel image;
ImageIcon ic;
Image img;
Main() {
j = new JFrame("Image Viewer");
j.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
// j.setExtendedState(Frame.MAXIMIZED_BOTH);
// j.setLocationRelativeTo(null);
j.setLocationByPlatform(true);
j.setLayout(new GridBagLayout());
GridBagConstraints c = new GridBagConstraints();
jpanel = new JPanel();
c.anchor = GridBagConstraints.PAGE_START;
c.fill = GridBagConstraints.HORIZONTAL;
c.gridx = c.gridy = 0;
c.gridwidth = 2;
// c.weightx=0.1;
c.weighty = 0.1;
c.ipady = 600;
c.insets = new Insets(5, 5, 10, 5);
// jpanel.setBackground(Color.BLACK);
j.add(jpanel, c);
jpanelbar = new JPanel();
jpanelbar.setBackground(Color.red);
c.weightx = 0.1;
c.gridx = 0;
c.gridy = 1;
c.fill = GridBagConstraints.HORIZONTAL;
c.insets = new Insets(5, 5, 5, 5);
c.ipady = 150;
j.add(jpanelbar, c);
jpanelbar.setLayout(new GridBagLayout());
GridBagConstraints x = new GridBagConstraints();
jpre = new JButton("Previous");
x.gridx = 0;
x.gridy = 0;
x.gridwidth = 1;
x.weightx = 0.1;
// x.insets=new Insets(5,5,5,5);
// x.fill=GridBagConstraints.NONE;
jpanelbar.add(jpre, x);
jnext = new JButton("Next");
x.gridx = 1;
jpanelbar.add(jnext, x);
// Creating Menu
jbar = new JMenuBar();
jmenu = new JMenu("File");
jmi = new JMenuItem("Open");
jmi.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent ae) {
JFileChooser fc = new JFileChooser();
int result = fc.showOpenDialog(null);
if (result == JFileChooser.APPROVE_OPTION) {
File file = fc.getSelectedFile();
String sname = file.getName();
image = new JLabel("", new ImageIcon(sname), JLabel.CENTER);
jpanel.add(image, BorderLayout.CENTER);
jpanel.revalidate();
jpanel.repaint();
}
}
});
jexit = new JMenuItem("Exit");
jexit.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent ae) {
System.exit(0);
}
});
jmenu.add(jmi);
jmenu.add(jexit);
jbar.add(jmenu);
j.setJMenuBar(jbar);
j.setSize(800, 600);
j.setResizable(false);
j.setVisible(true);
}
public static void main(String s[]) {
SwingUtilities.invokeLater(new Runnable() {
public void run() {
new Main();
}
});
}
}