如何创建带有图标和文本的 JList? [英] How to create JList with icon and text?

问题描述

我有这段代码想让 JList 谈论文本和图标必须做什么.
有些人建议我制作标签列表，并在表格中放置一个图标，这可能吗?如何?

I have this code want to make JList talk text and icon what must to do.
Some persons advice me to make list of label and in table put text an icon is it Possible? How?

在 ///////////////// 上搜索嵌入的注释.

Search on ///////////////// for embedded comment.

import javax.swing.JPanel;
import javax.swing.JButton;
import javax.swing.JLabel;
import java.awt.datatransfer.DataFlavor;
import java.awt.datatransfer.Transferable;
import java.awt.datatransfer.UnsupportedFlavorException;
import java.awt.dnd.DropTarget;
import java.awt.dnd.DropTargetDragEvent;
import java.awt.dnd.DropTargetDropEvent;
import java.awt.dnd.DropTargetEvent;
import java.awt.dnd.DropTargetListener;
import java.io.File;
import java.io.IOException;
import java.util.List;
import javax.swing.DefaultListModel;
import javax.swing.Icon;
import javax.swing.JList;
import javax.swing.JScrollPane;
import javax.swing.filechooser.FileSystemView;

public class pan extends JPanel implements DropTargetListener {

private DefaultListModel listModel = new DefaultListModel();
private DropTarget dropTarget;
private JLabel jLabel1;
private JScrollPane jScrollPane1;
private JList list;

/**
 * Create the panel.
 */
public pan() {
    setLayout(null);        
    list = new JList();
    dropTarget = new DropTarget(list, this);
    list.setModel(listModel);
    list.setDragEnabled(true);
    //list.setTransferHandler(new FileTransferHandler());
    jScrollPane1 = new JScrollPane();

    jScrollPane1.setViewportView(list);
    jScrollPane1.setBounds(10, 150, 635, 330);
    add(jScrollPane1);

}
public void dragEnter(DropTargetDragEvent arg0) {
    // nothing
}

public void dragOver(DropTargetDragEvent arg0) {
    // nothing
}

public void dropActionChanged(DropTargetDragEvent arg0) {
    // nothing
}

public void dragExit(DropTargetEvent arg0) {
    // nothing
}

public void drop(DropTargetDropEvent evt) {
    int action = evt.getDropAction();
    evt.acceptDrop(action);
    try {
        Transferable data = evt.getTransferable();
        if (data.isDataFlavorSupported(DataFlavor.javaFileListFlavor)) {
              List<File> files = (List<File>) data.getTransferDat(DataFlavor.javaFileListFlavor);
            for (File file : files) {

    Icon icon=FileSystemView.getFileSystemView().getSystemIcon(file);
/////////////////listModel.addElement(filepath+icon);///////////////////////want code do this

            }
        }
    } catch (UnsupportedFlavorException e) {
        e.printStackTrace();
    } catch (IOException e) {
        e.printStackTrace();
    } finally {
        evt.dropComplete(true);
    }
 }

}

解决这个问题后，如果双击它会打开桌面，我将为每个元素添加动作
到存储在列表中的路径.

After solve this problem i will add action to each element if doubel click on it will open desktop
to path stored in list.

推荐答案

import java.awt.*;
import java.awt.datatransfer.*;
import java.awt.dnd.*;
import javax.swing.*;
import javax.swing.border.LineBorder;
import javax.swing.filechooser.FileSystemView;
import java.io.*;
import java.util.List;

public class FileDropList extends JPanel implements DropTargetListener {

    private DefaultListModel listModel = new DefaultListModel();
    private DropTarget dropTarget;
    private JLabel jLabel1;
    private JScrollPane jScrollPane1;
    private JList list;

    /**
     * Create the panel.
     */
    public FileDropList() {
        //setLayout(null);        
        list = new JList();
        dropTarget = new DropTarget(list, this);
        list.setModel(listModel);
        list.setDragEnabled(true);
        FileListCellRenderer renderer = new FileListCellRenderer();
        list.setCellRenderer(renderer);
        //list.setTransferHandler(new FileTransferHandler());
        jScrollPane1 = new JScrollPane(list);

        //jScrollPane1.setBounds(10, 150, 635, 330);
        add(jScrollPane1);

    }
    public static void main(String[] args) throws Exception {
        Runnable r = new Runnable() {
            @Override
            public void run() {
                JPanel pan = new FileDropList();
                pan.setBorder(new LineBorder(Color.BLACK));
                JOptionPane.showMessageDialog(null, pan);
            }
        };
        SwingUtilities.invokeLater(r);
    }

    public void dragEnter(DropTargetDragEvent arg0) {
        // nothing
    }

    public void dragOver(DropTargetDragEvent arg0) {
        // nothing
    }

    public void dropActionChanged(DropTargetDragEvent arg0) {
        // nothing
    }

    public void dragExit(DropTargetEvent arg0) {
        // nothing
    }

    public void drop(DropTargetDropEvent evt) {
        int action = evt.getDropAction();
        evt.acceptDrop(action);
        try {
            Transferable data = evt.getTransferable();
            if (data.isDataFlavorSupported(DataFlavor.javaFileListFlavor)) {
                List<File> files = (List<File>) data.getTransferData(DataFlavor.javaFileListFlavor);
                for (File file : files) {
                    listModel.addElement(file);
                }
            }
        } catch (UnsupportedFlavorException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            evt.dropComplete(true);
        }
    }
}

/** A FileListCellRenderer for a File. */
class FileListCellRenderer extends DefaultListCellRenderer {

    private static final long serialVersionUID = -7799441088157759804L;
    private FileSystemView fileSystemView;
    private JLabel label;
    private Color textSelectionColor = Color.BLACK;
    private Color backgroundSelectionColor = Color.CYAN;
    private Color textNonSelectionColor = Color.BLACK;
    private Color backgroundNonSelectionColor = Color.WHITE;

    FileListCellRenderer() {
        label = new JLabel();
        label.setOpaque(true);
        fileSystemView = FileSystemView.getFileSystemView();
    }

    @Override
    public Component getListCellRendererComponent(
            JList list,
            Object value,
            int index,
            boolean selected,
            boolean expanded) {

        File file = (File)value;
        label.setIcon(fileSystemView.getSystemIcon(file));
        label.setText(fileSystemView.getSystemDisplayName(file));
        label.setToolTipText(file.getPath());

        if (selected) {
            label.setBackground(backgroundSelectionColor);
            label.setForeground(textSelectionColor);
        } else {
            label.setBackground(backgroundNonSelectionColor);
            label.setForeground(textNonSelectionColor);
        }

        return label;
    }
}

原答案

import java.awt.datatransfer.*;
import java.awt.dnd.*;
import javax.swing.*;
import javax.swing.filechooser.FileSystemView;
import java.io.*;
import java.util.List;

public class FileDragList extends JPanel implements DropTargetListener {

    private static final long serialVersionUID = 1L;
    private DefaultListModel listModel = new DefaultListModel();
    private JScrollPane jScrollPane1;
    private JList list;

    /**
     * Create the panel.
     */
    public FileDragList() {
        setLayout(null);        
        list = new JList();
        DropTarget dropTarget = new DropTarget(list, this);
        list.setModel(listModel);
        list.setDragEnabled(true);
        FileListCellRenderer renderer = new FileListCellRenderer();
        list.setCellRenderer(renderer);
        //list.setTransferHandler(new FileTransferHandler());
        jScrollPane1 = new JScrollPane();

        jScrollPane1.setViewportView(list);
        jScrollPane1.setBounds(10, 150, 635, 330);
        add(jScrollPane1);

    }
    public static void main(String[] args) throws Exception {
        Runnable r = new Runnable() {
            @Override
            public void run() {
                JOptionPane.showMessageDialog(null, new FileDragList());
            }
        };
        SwingUtilities.invokeLater(r);
    }

    public void dragEnter(DropTargetDragEvent arg0) {
        // nothing
    }

    public void dragOver(DropTargetDragEvent arg0) {
        // nothing
    }

    public void dropActionChanged(DropTargetDragEvent arg0) {
        // nothing
    }

    public void dragExit(DropTargetEvent arg0) {
        // nothing
    }

    public void drop(DropTargetDropEvent evt) {
        int action = evt.getDropAction();
        evt.acceptDrop(action);
        try {
            Transferable data = evt.getTransferable();
            if (data.isDataFlavorSupported(DataFlavor.javaFileListFlavor)) {
                List<File> files = (List<File>) data.getTransferData(DataFlavor.javaFileListFlavor);
                for (File file : files) {

                    Icon icon=FileSystemView.getFileSystemView().getSystemIcon(file);
                    /////////////////listModel.addElement(filepath+icon);///////////////////////want code do this

                }
            }
        } catch (UnsupportedFlavorException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            evt.dropComplete(true);
        }
    }
}

<小时>

Icon icon=FileSystemView.getFileSystemView().getSystemIcon(file);

哦，对了.尝试 文件浏览器 GUI 的 FileTreeCellRenderer 的变体.

Oh right.. Try a variant of the FileTreeCellRenderer of File Browser GUI.

就是这样，用于左边的树.

That's it, used for the tree on the left.

/** A TreeCellRenderer for a File. */
class FileTreeCellRenderer extends DefaultTreeCellRenderer {

    private FileSystemView fileSystemView;
    private JLabel label;

    FileTreeCellRenderer() {
        label = new JLabel();
        label.setOpaque(true);
        fileSystemView = FileSystemView.getFileSystemView();
    }

    @Override
    public Component getTreeCellRendererComponent(
        JTree tree,
        Object value,
        boolean selected,
        boolean expanded,
        boolean leaf,
        int row,
        boolean hasFocus) {

        DefaultMutableTreeNode node = (DefaultMutableTreeNode)value;
        File file = (File)node.getUserObject();
        label.setIcon(fileSystemView.getSystemIcon(file));
        label.setText(fileSystemView.getSystemDisplayName(file));
        label.setToolTipText(file.getPath());

        if (selected) {
            label.setBackground(backgroundSelectionColor);
            label.setForeground(textSelectionColor);
        } else {
            label.setBackground(backgroundNonSelectionColor);
            label.setForeground(textNonSelectionColor);
        }

        return label;
    }
}

更新

一个 SSCCE，它为列表调整了上面的渲染器.

Update

An SSCCE that adapts the renderer above for lists.

import java.awt.*;
import javax.swing.*;
import javax.swing.filechooser.FileSystemView;
import java.io.File;

public class FileList {
    public static void main(String[] args) throws Exception {
        Runnable r = new Runnable() {
            @Override
            public void run() {
                JPanel gui = new JPanel(new BorderLayout(2,2));

                File userHome = new File(System.getProperty("user.home"));
                File[] files = userHome.listFiles();
                JList list = new JList(files);
                list.setCellRenderer(new FileListCellRenderer());
                gui.add(new JScrollPane(list));

                JOptionPane.showMessageDialog(null, gui);
            }
        };
        SwingUtilities.invokeLater(r);
    }
}

/** A FileListCellRenderer for a File. */
class FileListCellRenderer extends DefaultListCellRenderer {

    private static final long serialVersionUID = -7799441088157759804L;
    private FileSystemView fileSystemView;
    private JLabel label;
    private Color textSelectionColor = Color.BLACK;
    private Color backgroundSelectionColor = Color.CYAN;
    private Color textNonSelectionColor = Color.BLACK;
    private Color backgroundNonSelectionColor = Color.WHITE;

    FileListCellRenderer() {
        label = new JLabel();
        label.setOpaque(true);
        fileSystemView = FileSystemView.getFileSystemView();
    }

    @Override
    public Component getListCellRendererComponent(
        JList list,
        Object value,
        int index,
        boolean selected,
        boolean expanded) {

        File file = (File)value;
        label.setIcon(fileSystemView.getSystemIcon(file));
        label.setText(fileSystemView.getSystemDisplayName(file));
        label.setToolTipText(file.getPath());

        if (selected) {
            label.setBackground(backgroundSelectionColor);
            label.setForeground(textSelectionColor);
        } else {
            label.setBackground(backgroundNonSelectionColor);
            label.setForeground(textNonSelectionColor);
        }

        return label;
    }
}

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