向每个表格单元格添加进度条以获取文件进度 - Java

adding progress bar to each table cell for file progress - Java

提问by rogerthat

The application encrypts each file that is put into the table when you click encrypt and I would like to show the progress of the files as they are being encrypted. The "Status" column will then change from "Not Processed" to "Processed."

当您单击加密时，应用程序会加密放入表中的每个文件，我想显示文件加密的进度。然后“状态”列将从“未处理”更改为“已处理”。

Similar to the way you watch multiple files attach in an email. I've been looking into the cell renderer and the ProgressBarTablecell but am unsure how to go about implementing them. Any help appreciated. I'm posting the table.

类似于您观看电子邮件中附加的多个文件的方式。我一直在研究单元格渲染器和 ProgressBarTablecell，但不确定如何实现它们。任何帮助表示赞赏。我正在张贴表格。

        import java.awt.BorderLayout;
    import java.awt.Color;
    import java.awt.Dimension;
    import java.awt.EventQueue;
    import java.awt.Point;
    import java.awt.datatransfer.DataFlavor;
    import java.awt.datatransfer.Transferable;
    import java.awt.datatransfer.UnsupportedFlavorException;
    import java.awt.dnd.DnDConstants;
    import java.awt.dnd.DropTarget;
    import java.awt.dnd.DropTargetDragEvent;
    import java.awt.dnd.DropTargetDropEvent;
    import java.io.File;
    import java.io.IOException;
    import java.util.List;

    import javax.swing.JFrame;
    import javax.swing.JPanel;
    import javax.swing.JScrollPane;
    import javax.swing.JTable;
    import javax.swing.UIManager;
    import javax.swing.UnsupportedLookAndFeelException;
    import javax.swing.table.DefaultTableModel;

    public class DropTable {

        public static void main(String[] args) {
            new DropTable();
        }

        public DropTable() {
            EventQueue.invokeLater(new Runnable() {
                @Override
                public void run() {
                    try {
                        UIManager.setLookAndFeel(UIManager
                                .getSystemLookAndFeelClassName());//get look and feel of whatever OS we're using
                    } catch (ClassNotFoundException | InstantiationException
                            | IllegalAccessException
                            | UnsupportedLookAndFeelException ex) {
                    }

                    JFrame frame = new JFrame();
                    frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
                    frame.setLayout(new BorderLayout());
                    frame.add(new DropPane());
                    frame.pack();
                    frame.setLocationRelativeTo(null);
                    frame.setVisible(true);
                }

            });
        }

        public class DropPane extends JPanel {

            /**
             * 
             */
            private static final long serialVersionUID = 1L;
            private JTable table;
            private JScrollPane scroll;
            private DefaultTableModel tm = new DefaultTableModel(new String[] {
                    "File", "File Type", "Size", "Status" }, 0);

            public DropPane() {
                table = new JTable();
                table.setShowGrid(true);
                table.setShowHorizontalLines(true);
                table.setShowVerticalLines(true);
                table.setGridColor(Color.GRAY);


                table.setModel(tm);
                table.setFillsViewportHeight(true);
                table.setPreferredSize(new Dimension(500, 300));

                scroll = new JScrollPane(table);

                table.setDropTarget(new DropTarget() {
                    @Override
                    public synchronized void dragOver(DropTargetDragEvent dtde) {
                        Point point = dtde.getLocation();
                        int row = table.rowAtPoint(point);
                        if (row < 0) {
                            table.clearSelection();
                        } else {
                            table.setRowSelectionInterval(row, row);
                        }
                        dtde.acceptDrag(DnDConstants.ACTION_COPY_OR_MOVE);
                    }

                    @Override
                    public synchronized void drop(DropTargetDropEvent dtde) {
                        if (dtde.isDataFlavorSupported(DataFlavor.javaFileListFlavor))
                        {//make sure the flavors are files
                            dtde.acceptDrop(DnDConstants.ACTION_COPY_OR_MOVE);//dndconstants tells what to do with the drag files
                            //change to ACTION_COPY so it removes the file from the directory
                            Transferable t = dtde.getTransferable();
                            List fileList = null;
                            try {
                                fileList = (List) t.getTransferData(DataFlavor.javaFileListFlavor);//get file
                                if (fileList.size() > 0) {
                                    table.clearSelection();
                                    Point point = dtde.getLocation();//point is (x,y) 
                                    int row = table.rowAtPoint(point);
                                    DefaultTableModel model = (DefaultTableModel) table.getModel();
                                    for (Object value : fileList) {
                                        if (value instanceof File) {
                                            File f = (File) value;

                                            if (row < 0) {//insert rows into the right columns
                                            model.addRow(new Object[]{f.getAbsolutePath(), "", f.length(), "", ""});//path under "File"
                                            } else {
                                                model.insertRow(row, new Object[]{f.getAbsolutePath(), "", f.length(), "", ""});//get size of file
                                                row++;

                                            }
                                        }
                                    }
                                }
                            } catch (UnsupportedFlavorException e) {
                                e.printStackTrace();
                            } catch (IOException e) {
                                e.printStackTrace();
                            }
                        } else {
                            dtde.rejectDrop();
                        }
                    }

                });

                add(scroll, BorderLayout.CENTER);
            }
        }
    }

回答by MadProgrammer

Here is a basic example, this basically uses a SwingWorkerto scan the root directory of your drive and lists all the files. Once that's completed, it will attempt to read each file, in it's own SwingWorkerupdating the table as it goes.

这是一个基本示例，它基本上使用 aSwingWorker来扫描驱动器的根目录并列出所有文件。完成后，它将尝试读取每个文件，并自行SwingWorker更新表。

Disclaimer: This is an example. I use a Thread.sleepto slow the reads down slightly, ignore the buffers and a few other things I would do it differently in production code, but I wanted to highlight the progress updates.

免责声明：这是一个例子。我使用 aThread.sleep稍微减慢读取速度，忽略缓冲区和其他一些我会在生产代码中做不同的事情，但我想突出显示进度更新。

How it works

怎么运行的

First, you need a cell renderer capable of displaying progress updates. I've chosen a simple custom JProgressBar, but you might like something a little more sophisticated.

首先，您需要一个能够显示进度更新的单元格渲染器。我选择了一个简单的 custom JProgressBar，但您可能喜欢更复杂的东西。

You need some way to update the table model. I've chose to provide a simple updateStatusmethod, passing the file I'm updating, this allows me to use internal look ups to find the row in question. I then use the setValueAtmethod to update the row object. This is not really required, but I wanted to demonstrate the use of the setValueAtmethod, you could have updated the row object from the updateStatusmethod directly.

您需要某种方式来更新表模型。我选择提供一个简单的updateStatus方法，传递我正在更新的文件，这允许我使用内部查找来查找有问题的行。然后我使用该setValueAt方法更新行对象。这不是真正必需的，但我想演示该setValueAt方法的使用，您可以updateStatus直接从该方法更新行对象。

And finally, notify the table of changes to the model so it will repaint itself.

最后，将模型更改通知表，以便它重新绘制自己。

public class UpdateTable {

    public static void main(String[] args) {
        new UpdateTable();
    }

    public UpdateTable() {
        EventQueue.invokeLater(new Runnable() {
            @Override
            public void run() {
                try {
                    UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
                } catch (ClassNotFoundException | InstantiationException | IllegalAccessException | UnsupportedLookAndFeelException ex) {
                }

                UpdatableTableModel model = new UpdatableTableModel();

                JTable table = new JTable();
                table.setModel(model);

                table.getColumn("Status").setCellRenderer(new ProgressCellRender());

                JFrame frame = new JFrame();
                frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
                frame.setLayout(new BorderLayout());
                frame.add(new JScrollPane(table));
                frame.pack();
                frame.setLocationRelativeTo(null);
                frame.setVisible(true);

                FileFinderWorker worker = new FileFinderWorker(model);
                worker.execute();

            }
        });
    }

    public class ProgressCellRender extends JProgressBar implements TableCellRenderer {

        @Override
        public Component getTableCellRendererComponent(JTable table, Object value, boolean isSelected, boolean hasFocus, int row, int column) {
            int progress = 0;
            if (value instanceof Float) {
                progress = Math.round(((Float) value) * 100f);
            } else if (value instanceof Integer) {
                progress = (int) value;
            }
            setValue(progress);
            return this;
        }
    }

    public class RowData {

        private File file;
        private String type;
        private long length;
        private float status;

        public RowData(File file, String type) {
            this.file = file;
            this.type = type;
            this.length = file.length();
            this.status = 0f;
        }

        public File getFile() {
            return file;
        }

        public long getLength() {
            return length;
        }

        public float getStatus() {
            return status;
        }

        public String getType() {
            return type;
        }

        public void setStatus(float status) {
            this.status = status;
        }
    }

    public class UpdatableTableModel extends AbstractTableModel {

        private List<RowData> rows;
        private Map<File, RowData> mapLookup;

        public UpdatableTableModel() {
            rows = new ArrayList<>(25);
            mapLookup = new HashMap<>(25);
        }

        @Override
        public int getRowCount() {
            return rows.size();
        }

        @Override
        public int getColumnCount() {
            return 4;
        }

        @Override
        public String getColumnName(int column) {
            String name = "??";
            switch (column) {
                case 0:
                    name = "File";
                    break;
                case 1:
                    name = "File Type";
                    break;
                case 2:
                    name = "Size";
                    break;
                case 3:
                    name = "Status";
                    break;
            }
            return name;
        }

        @Override
        public Object getValueAt(int rowIndex, int columnIndex) {
            RowData rowData = rows.get(rowIndex);
            Object value = null;
            switch (columnIndex) {
                case 0:
                    value = rowData.getFile();
                    break;
                case 1:
                    value = rowData.getType();
                    break;
                case 2:
                    value = rowData.getLength();
                    break;
                case 3:
                    value = rowData.getStatus();
                    break;
            }
            return value;
        }

        @Override
        public void setValueAt(Object aValue, int rowIndex, int columnIndex) {
            RowData rowData = rows.get(rowIndex);
            switch (columnIndex) {
                case 3:
                    if (aValue instanceof Float) {
                        rowData.setStatus((float) aValue);
                    }
                    break;
            }
        }

        public void addFile(File file) {
            RowData rowData = new RowData(file, "A File");
            mapLookup.put(file, rowData);
            rows.add(rowData);
            fireTableRowsInserted(rows.size() - 1, rows.size() - 1);
        }

        protected void updateStatus(File file, int progress) {
            RowData rowData = mapLookup.get(file);
            if (rowData != null) {
                int row = rows.indexOf(rowData);
                float p = (float) progress / 100f;
                setValueAt(p, row, 3);
                fireTableCellUpdated(row, 3);
            }
        }
    }

    public class FileFinderWorker extends SwingWorker<List<File>, File> {

        private UpdatableTableModel model;

        public FileFinderWorker(UpdatableTableModel model) {
            this.model = model;
        }

        @Override
        protected void process(List<File> chunks) {
            for (File file : chunks) {
                model.addFile(file);
            }
        }

        @Override
        protected List<File> doInBackground() throws Exception {
            File files[] = new File(System.getProperty("user.dir")).listFiles();
            List<File> lstFiles = new ArrayList<>(Arrays.asList(files));
            for (File file : lstFiles) {
                // You could actually publish the entire array, but I'm doing this
                // deliberatly ;)
                publish(file);
            }
            return lstFiles;
        }

        @Override
        protected void done() {
            try {
                List<File> files = get();
                for (File file : files) {
                    new FileReaderWorker(model, file).execute();
                }
            } catch (Exception exp) {
                exp.printStackTrace();
            }
        }
    }

    public class FileReaderWorker extends SwingWorker<File, File> {

        private File currentFile;
        private UpdatableTableModel model;

        public FileReaderWorker(UpdatableTableModel model, File file) {
            this.currentFile = file;
            this.model = model;

            addPropertyChangeListener(new PropertyChangeListener() {
                @Override
                public void propertyChange(PropertyChangeEvent evt) {
                    if (evt.getPropertyName().equals("progress")) {
                        FileReaderWorker.this.model.updateStatus(currentFile, (int) evt.getNewValue());
                    }
                }
            });

        }

        @Override
        protected File doInBackground() throws Exception {
            if (currentFile.isFile()) {
                setProgress(0);
                long fileLength = currentFile.length();
                BufferedReader reader = null;
                char[] cbuf = new char[1024];
                try {
                    reader = new BufferedReader(new FileReader(currentFile));
                    int bytesRead = -1;
                    int totalBytesRead = 0;
                    while ((bytesRead = reader.read(cbuf)) != -1) {
                        totalBytesRead += bytesRead;
                        int progress = (int) Math.round(((double) totalBytesRead / (double) fileLength) * 100d);
                        setProgress(progress);
                        Thread.sleep(25);
                    }
                    setProgress(100);
                } catch (Exception e) {
                    e.printStackTrace();
                    setProgress(100);
                } finally {
                    try {
                        reader.close();
                    } catch (Exception e) {
                    }
                }
            } else {
                setProgress(100);
            }
            return currentFile;
        }
    }
}

Important concepts.

重要概念。

NEVER, EVER block the Event Dispatching Thread with any kind of long running operation. Instead, move these time consuming operations off into a background thread. Here, I've used SwingWorker

永远，永远不要用任何类型的长时间运行的操作阻塞事件调度线程。相反，将这些耗时的操作移到后台线程中。在这里，我用过SwingWorker

Have a read through Concurrency in Swingfor more info

阅读Swing中的并发以了解更多信息

回答by trashgod

You'll need a TableCellRendererthat contains a JProgressBar, as shown here. You can update each file's progress from a SwingWorker, seen here.

你需要一个TableCellRenderer包含JProgressBar，如图所示这里。您可以从 更新每个文件的进度SwingWorker，见这里。

回答by Oliver Watkins

You need to have some kind of a process with an integer value between 0 and 100. For example :

您需要某种整数值介于 0 和 100 之间的进程。例如：

class Process {

    public Process(String name, int progress, String description) {
        super();
        this.name = name;
        this.progress = progress;
        this.description = description;
    }

    String name;
    int progress;
    String description; }

This gets modelled in the tables tableModel.

这在表 tableModel 中建模。

A renderer is needed to return a progress bar on one of the tables columns :

需要渲染器来返回表列之一上的进度条：

class ProgressRenderer extends DefaultTableCellRenderer {
    public Component getTableCellRendererComponent(JTable table, Object value, boolean isSelected,
            boolean hasFocus, int row2, int column) {

        int row = table.convertRowIndexToModel(row2);

        ProcessTableModel mtm = (ProcessTableModel) table.getModel();
        Process p = (Process) mtm.getProcessAt(row);

        JProgressBar bar = new JProgressBar();
        bar.setValue(p.progress);
        return bar;
    }
}

Now you just need a thread to be doing something in the background and updating the process objects. The complete example, of which I have copied snippets of code, can be found here.

现在你只需要一个线程在后台做一些事情并更新进程对象。我复制了代码片段的完整示例可以在这里找到。