Java JPanel不在JFrame中显示？
我正在用Java创建一个MP3tager应用程序，使用JAudioTagger 该应用程序实际上显示了曲目的标题、编号、专辑、艺术家、年份、流派以及元数据中包含的评论。 它应该在主框架一角的JPanel上显示相册的艺术作品。。。但事实并非如此。 我认为Jpanel不起作用：它既不显示JTextField也不显示Button。。。 守则：Java JPanel不在JFrame中显示？,java,swing,jpanel,Java,Swing,Jpanel,我正在用Java创建一个MP3tager应用程序，使用JAudioTagger 该应用程序实际上显示了曲目的标题、编号、专辑、艺术家、年份、流派以及元数据中包含的评论。 它应该在主框架一角的JPanel上显示相册的艺术作品。。。但事实并非如此。 我认为Jpanel不起作用：它既不显示JTextField也不显示Button。。。 守则： class JPanelArt extends JComponent { private static final long serialVersio
class JPanelArt extends JComponent {
private static final long serialVersionUID = 1L;
private Image image;
public JPanelArt() {
try {
image = ImageIO.read(new File("res/download.jpg"));
} catch (IOException e) {}
}
protected void paintComponent(Graphics g) {
if (image == null)
return;
g.drawImage(image, 0, 0, null);
}
}
public class Mp3TaggerFrame extends JFrame {
private static final long serialVersionUID = 1L;
static AudioFile mp3;
private JPanel contentPane;
private JPanelArt albumArt;
private JLabel imageArt;
private JTextField titleTrack;
private JTextField artist;
private JTextField album;
private JTextField genre;
private JTextField trackNumber;
private JTextField lenght;
private JTextField year;
private JTextField comment;
private JTextField bitRate;
JFileChooser chooser = new JFileChooser();
FileNameExtensionFilter filter = new FileNameExtensionFilter("Mp3 File",
"mp3");
public void setAlbumArt(BufferedImage _image) {
}
public String getTitleTrack() {
return titleTrack.getText();
}
public void setTitleTrack(String title) {
this.titleTrack.setText(title);
}
public String getArtist() {
return artist.getText();
}
public void setArtist(String artist) {
this.artist.setText(artist);
}
public String getAlbum() {
return album.getText();
}
public void setAlbum(String album) {
this.album.setText(album);
}
public String getGenre() {
return genre.getText();
}
public void setGenre(String genre) {
this.genre.setText(genre);
}
public int getTrackNumber() {
return Integer.valueOf(trackNumber.getText());
}
public void setTrackNumber(String string) {
this.trackNumber.setText(string);
}
public void setLenght(int lenght) {
int min = 0;
int sec = lenght;
while (sec >= 60) {
sec = sec - 60;
min++;
}
this.lenght.setText(String.valueOf(min) + ":" + String.valueOf(sec));
}
public int getYear() {
return Integer.valueOf(year.getText());
}
public void setYear(String year) {
this.year.setText(year);
}
public String getComment() {
return comment.getText();
}
public void setComment(String comment) {
this.comment.setText(comment);
}
public String getBitRate() {
return bitRate.getText();
}
public void setBitRate(String bitRate) {
this.bitRate.setText(bitRate);
}
/**
* Create the frame.
*/
public Mp3TaggerFrame() {
try {
UIManager.setLookAndFeel(new SyntheticaBlackStarLookAndFeel());
} catch (Exception e) {
}
chooser.setFileFilter(filter);
setFont(new Font("Century Schoolbook", Font.PLAIN, 14));
setResizable(false);
setTitle("Mp3Tagger");
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
setBounds(100, 100, 562, 423);
setIconImage(new ImageIcon("res/Icon.png").getImage());
JMenuBar menuBar = new JMenuBar();
setJMenuBar(menuBar);
JMenu mnFile = new JMenu("File");
menuBar.add(mnFile);
JMenuItem openMp3File = new JMenuItem("Open Mp3 File");
mnFile.add(openMp3File);
openMp3File.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
openFile();
}
});
JMenuItem saveWithNewTag = new JMenuItem("Save With New Tag");
mnFile.add(saveWithNewTag);
saveWithNewTag.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent arg0) {
saveFile();
}
});
JMenuItem mntmExit = new JMenuItem("Exit");
mnFile.add(mntmExit);
JMenu mnAbout = new JMenu("About");
menuBar.add(mnAbout);
JMenuItem mntmAboutTheProgram = new JMenuItem("About The Program");
mnAbout.add(mntmAboutTheProgram);
JMenuItem mntmContacts = new JMenuItem("Contacts");
mnAbout.add(mntmContacts);
contentPane = new JPanel();
contentPane.setBorder(new EmptyBorder(5, 5, 5, 5));
setContentPane(contentPane);
contentPane.setLayout(null);
JLabel lblTitle = new JLabel("Title:");
lblTitle.setFont(new Font("DokChampa", Font.PLAIN, 15));
lblTitle.setBounds(6, 6, 122, 28);
contentPane.add(lblTitle);
titleTrack = new JTextField();
titleTrack.setToolTipText("Title Of The Track");
titleTrack.setBounds(6, 32, 122, 28);
contentPane.add(titleTrack);
titleTrack.setColumns(10);
JLabel lblArtist = new JLabel("Artist:");
lblArtist.setFont(new Font("DokChampa", Font.PLAIN, 15));
lblArtist.setBounds(6, 72, 122, 28);
contentPane.add(lblArtist);
artist = new JTextField();
artist.setToolTipText("Artist");
artist.setColumns(10);
artist.setBounds(6, 98, 122, 28);
contentPane.add(artist);
JLabel lblAlbum = new JLabel("Album:");
lblAlbum.setFont(new Font("DokChampa", Font.PLAIN, 15));
lblAlbum.setBounds(6, 138, 122, 28);
contentPane.add(lblAlbum);
album = new JTextField();
album.setToolTipText("Album");
album.setColumns(10);
album.setBounds(6, 164, 122, 28);
contentPane.add(album);
JLabel lblGenre = new JLabel("Genre:");
lblGenre.setFont(new Font("DokChampa", Font.PLAIN, 15));
lblGenre.setBounds(6, 270, 122, 28);
contentPane.add(lblGenre);
genre = new JTextField();
genre.setToolTipText("Genre Of The Track");
genre.setColumns(10);
genre.setBounds(6, 296, 122, 28);
contentPane.add(genre);
JLabel lblTrackNumber = new JLabel("Track Number:");
lblTrackNumber.setFont(new Font("DokChampa", Font.PLAIN, 15));
lblTrackNumber.setBounds(6, 204, 122, 28);
contentPane.add(lblTrackNumber);
trackNumber = new JTextField();
trackNumber.setToolTipText("Number of the track in the album");
trackNumber.setColumns(10);
trackNumber.setBounds(6, 230, 122, 28);
contentPane.add(trackNumber);
JLabel lblAlbumArt = new JLabel("Album Art");
lblAlbumArt.setFont(new Font("DokChampa", Font.PLAIN, 15));
lblAlbumArt.setBounds(375, 6, 73, 28);
contentPane.add(lblAlbumArt);
albumArt = new JPanelArt();
albumArt.setToolTipText("The Album Cover");
albumArt.setBounds(375, 192, 150, -150);
contentPane.add(albumArt);
JLabel lblLenght = new JLabel("Lenght");
lblLenght.setFont(new Font("DokChampa", Font.PLAIN, 15));
lblLenght.setBounds(375, 204, 122, 28);
contentPane.add(lblLenght);
lenght = new JTextField();
lenght.setEditable(false);
lenght.setToolTipText("Lenght of the song");
lenght.setColumns(10);
lenght.setBounds(375, 230, 122, 28);
contentPane.add(lenght);
JButton editAlbumArt = new JButton("Edit");
editAlbumArt.setBounds(460, 6, 55, 28);
contentPane.add(editAlbumArt);
JLabel lblYear = new JLabel("Year:");
lblYear.setFont(new Font("DokChampa", Font.PLAIN, 15));
lblYear.setBounds(181, 6, 122, 28);
contentPane.add(lblYear);
year = new JTextField();
year.setToolTipText("Year Of The Track");
year.setColumns(10);
year.setBounds(181, 32, 122, 28);
contentPane.add(year);
JLabel lblComments = new JLabel("Comments:");
lblComments.setFont(new Font("DokChampa", Font.PLAIN, 15));
lblComments.setBounds(181, 72, 122, 28);
contentPane.add(lblComments);
comment = new JTextField();
comment.setToolTipText("Comments Of The Track");
comment.setColumns(10);
comment.setBounds(181, 98, 122, 160);
contentPane.add(comment);
JLabel lblBitrate = new JLabel("Bit Rate");
lblBitrate.setFont(new Font("DokChampa", Font.PLAIN, 15));
lblBitrate.setBounds(375, 270, 122, 28);
contentPane.add(lblBitrate);
bitRate = new JTextField();
bitRate.setToolTipText("BitRate of the song");
bitRate.setEditable(false);
bitRate.setColumns(10);
bitRate.setBounds(375, 296, 122, 28);
contentPane.add(bitRate);
}
private void openFile() {
if (chooser.showOpenDialog(chooser) == JFileChooser.APPROVE_OPTION) {
try {
mp3 = AudioFileIO.read((new File(chooser.getSelectedFile()
.getAbsolutePath())));
} catch (CannotReadException | IOException | TagException
| ReadOnlyFileException | InvalidAudioFrameException e) {
e.printStackTrace();
}
} else
System.out.println("Nessun File Selezionato");
setTextFields();
}
private void setTextFields() {
Tag tag = mp3.getTag();
AudioHeader ah = mp3.getAudioHeader();
setTitleTrack(tag.getFirst(FieldKey.TITLE));
setAlbum(tag.getFirst(FieldKey.ALBUM));
setArtist(tag.getFirst(FieldKey.ARTIST));
setGenre(tag.getFirst(FieldKey.GENRE));
setTrackNumber(tag.getFirst(FieldKey.TRACK));
setLenght(ah.getTrackLength());
setYear(tag.getFirst(FieldKey.YEAR));
setComment(tag.getFirst(FieldKey.COMMENT));
setBitRate(ah.getBitRate() + "Kbs");
try {
setAlbumArt((BufferedImage) tag.getFirstArtwork().getImage());
} catch (IOException e) {
e.printStackTrace();
}
}
private void saveFile() {
}
}
请注意，JPanelArt是一个JComponent而不是JFrame。定义中指出“op级别的Swing容器——如JFrame、JDialog和JApplet——是专门的组件，为其他Swing组件提供了自己绘制的位置”。您可以尝试两种解决方案：
JPanelJComponentmp3tagerframemp3tagerframemp3tagerframepaint（）方法中（在这种情况下，必须包含一些getGraphics
，才能获得面板图形）import java.awt.*;
import java.awt.event.*;
import java.awt.image.BufferedImage;
import javax.swing.*;
import javax.swing.border.EmptyBorder;
import javax.swing.filechooser.FileNameExtensionFilter;
public class Mp3TaggerFrame extends JFrame {
private static final long serialVersionUID = 1L;
private JPanel contentPane;
private JPanel albumArt;
private JLabel imageArt;
private JTextField titleTrack;
private JTextField artist;
private JTextField album;
private JTextField genre;
private JTextField trackNumber;
private JTextField lenght;
private JTextField year;
private JTextField comment;
private JTextField bitRate;
public static void main(String[] args) {
new Mp3TaggerFrame().setVisible(true);
}
JFileChooser chooser = new JFileChooser();
FileNameExtensionFilter filter = new FileNameExtensionFilter("Mp3 File",
"mp3");
public void setAlbumArt(BufferedImage _image) {
}
public String getTitleTrack() {
return titleTrack.getText();
}
public void setTitleTrack(String title) {
this.titleTrack.setText(title);
}
public String getArtist() {
return artist.getText();
}
public void setArtist(String artist) {
this.artist.setText(artist);
}
public String getAlbum() {
return album.getText();
}
public void setAlbum(String album) {
this.album.setText(album);
}
public String getGenre() {
return genre.getText();
}
public void setGenre(String genre) {
this.genre.setText(genre);
}
public int getTrackNumber() {
return Integer.valueOf(trackNumber.getText());
}
public void setTrackNumber(String string) {
this.trackNumber.setText(string);
}
public void setLenght(int lenght) {
int min = 0;
int sec = lenght;
while (sec >= 60) {
sec = sec - 60;
min++;
}
this.lenght.setText(String.valueOf(min) + ":" + String.valueOf(sec));
}
public int getYear() {
return Integer.valueOf(year.getText());
}
public void setYear(String year) {
this.year.setText(year);
}
public String getComment() {
return comment.getText();
}
public void setComment(String comment) {
this.comment.setText(comment);
}
public String getBitRate() {
return bitRate.getText();
}
public void setBitRate(String bitRate) {
this.bitRate.setText(bitRate);
}
/**
* Create the frame.
*/
public Mp3TaggerFrame() {
chooser.setFileFilter(filter);
setFont(new Font("Century Schoolbook", Font.PLAIN, 14));
setResizable(false);
setTitle("Mp3Tagger");
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
setBounds(100, 100, 562, 423);
setIconImage(new ImageIcon("res/Icon.png").getImage());
JMenuBar menuBar = new JMenuBar();
setJMenuBar(menuBar);
JMenu mnFile = new JMenu("File");
menuBar.add(mnFile);
JMenuItem openMp3File = new JMenuItem("Open Mp3 File");
mnFile.add(openMp3File);
openMp3File.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
openFile();
}
});
JMenuItem saveWithNewTag = new JMenuItem("Save With New Tag");
mnFile.add(saveWithNewTag);
saveWithNewTag.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent arg0) {
saveFile();
}
});
JMenuItem mntmExit = new JMenuItem("Exit");
mnFile.add(mntmExit);
JMenu mnAbout = new JMenu("About");
menuBar.add(mnAbout);
JMenuItem mntmAboutTheProgram = new JMenuItem("About The Program");
mnAbout.add(mntmAboutTheProgram);
JMenuItem mntmContacts = new JMenuItem("Contacts");
mnAbout.add(mntmContacts);
contentPane = new JPanel();
contentPane.setBorder(new EmptyBorder(5, 5, 5, 5));
setContentPane(contentPane);
contentPane.setLayout(null);
JLabel lblTitle = new JLabel("Title:");
lblTitle.setFont(new Font("DokChampa", Font.PLAIN, 15));
lblTitle.setBounds(6, 6, 122, 28);
contentPane.add(lblTitle);
titleTrack = new JTextField();
titleTrack.setToolTipText("Title Of The Track");
titleTrack.setBounds(6, 32, 122, 28);
contentPane.add(titleTrack);
titleTrack.setColumns(10);
JLabel lblArtist = new JLabel("Artist:");
lblArtist.setFont(new Font("DokChampa", Font.PLAIN, 15));
lblArtist.setBounds(6, 72, 122, 28);
contentPane.add(lblArtist);
artist = new JTextField();
artist.setToolTipText("Artist");
artist.setColumns(10);
artist.setBounds(6, 98, 122, 28);
contentPane.add(artist);
JLabel lblAlbum = new JLabel("Album:");
lblAlbum.setFont(new Font("DokChampa", Font.PLAIN, 15));
lblAlbum.setBounds(6, 138, 122, 28);
contentPane.add(lblAlbum);
album = new JTextField();
album.setToolTipText("Album");
album.setColumns(10);
album.setBounds(6, 164, 122, 28);
contentPane.add(album);
JLabel lblGenre = new JLabel("Genre:");
lblGenre.setFont(new Font("DokChampa", Font.PLAIN, 15));
lblGenre.setBounds(6, 270, 122, 28);
contentPane.add(lblGenre);
genre = new JTextField();
genre.setToolTipText("Genre Of The Track");
genre.setColumns(10);
genre.setBounds(6, 296, 122, 28);
contentPane.add(genre);
JLabel lblTrackNumber = new JLabel("Track Number:");
lblTrackNumber.setFont(new Font("DokChampa", Font.PLAIN, 15));
lblTrackNumber.setBounds(6, 204, 122, 28);
contentPane.add(lblTrackNumber);
trackNumber = new JTextField();
trackNumber.setToolTipText("Number of the track in the album");
trackNumber.setColumns(10);
trackNumber.setBounds(6, 230, 122, 28);
contentPane.add(trackNumber);
JLabel lblAlbumArt = new JLabel("Album Art");
lblAlbumArt.setFont(new Font("DokChampa", Font.PLAIN, 15));
lblAlbumArt.setBounds(375, 6, 73, 28);
contentPane.add(lblAlbumArt);
albumArt = new JPanel();
BufferedImage bi = new BufferedImage(150,150,BufferedImage.TYPE_INT_RGB);
albumArt.add(new JLabel(new ImageIcon(bi)));
albumArt.setToolTipText("The Album Cover");
albumArt.setBounds(375, 42, 150, 150);
contentPane.add(albumArt);
JLabel lblLenght = new JLabel("Lenght");
lblLenght.setFont(new Font("DokChampa", Font.PLAIN, 15));
lblLenght.setBounds(375, 204, 122, 28);
contentPane.add(lblLenght);
lenght = new JTextField();
lenght.setEditable(false);
lenght.setToolTipText("Lenght of the song");
lenght.setColumns(10);
lenght.setBounds(375, 230, 122, 28);
contentPane.add(lenght);
JButton editAlbumArt = new JButton("Edit");
editAlbumArt.setBounds(460, 6, 55, 28);
contentPane.add(editAlbumArt);
JLabel lblYear = new JLabel("Year:");
lblYear.setFont(new Font("DokChampa", Font.PLAIN, 15));
lblYear.setBounds(181, 6, 122, 28);
contentPane.add(lblYear);
year = new JTextField();
year.setToolTipText("Year Of The Track");
year.setColumns(10);
year.setBounds(181, 32, 122, 28);
contentPane.add(year);
JLabel lblComments = new JLabel("Comments:");
lblComments.setFont(new Font("DokChampa", Font.PLAIN, 15));
lblComments.setBounds(181, 72, 122, 28);
contentPane.add(lblComments);
comment = new JTextField();
comment.setToolTipText("Comments Of The Track");
comment.setColumns(10);
comment.setBounds(181, 98, 122, 160);
contentPane.add(comment);
JLabel lblBitrate = new JLabel("Bit Rate");
lblBitrate.setFont(new Font("DokChampa", Font.PLAIN, 15));
lblBitrate.setBounds(375, 270, 122, 28);
contentPane.add(lblBitrate);
bitRate = new JTextField();
bitRate.setToolTipText("BitRate of the song");
bitRate.setEditable(false);
bitRate.setColumns(10);
bitRate.setBounds(375, 296, 122, 28);
contentPane.add(bitRate);
}
private void openFile() {
}
private void setTextFields() {
}
private void saveFile() {
}
}
您不需要
JComponent#setVisible（）JFrame#pack（）JFrame#setVisible（）contentPane.setLayout（null）Java GUI必须在不同的操作系统、屏幕大小、屏幕分辨率等上工作。因此，它们不利于像素完美布局。而是使用布局管理器，或与布局填充和边框一起使用。这也可能是小组没有出现的原因。。但是按照@trashgood的建议发布一个MCVE以获得更明确的答案。你是说你没有看到类似的东西吗？顺便说一句，我把相册上的艺术增加了50个像素，因为它与最后两个标签重叠了。哇，D：你是怎么做到的？我还是看不到面板…你试过第二种方法吗？此外，JPanelArt中没有尺寸定义。我不知道默认设置，但可能是因为它不是不可见的，只是太小而看不见吗？我通过setBounds（）设置了面板的大小，注意它仍然是垃圾代码。当某物被移到窗口前面然后移开时，它会留下“画作”。与其使用null
布局，不如使用布局管理器（或多个）进行布局。成功了！谢谢你的帮助！我将完成这一步，然后启动另一步，使用布局管理器创建GUI！