当您点击加密时,应用程序会加密放入表中的每个文件,并且我想在显示加密文件时的进度. “状态”列将从“未处理”更改为“已处理”.
类似于您在电子邮件中附加多个文件的方式.我一直在研究细胞渲染器和ProgressBarTablecell,但不确定如何去实现它们.任何帮助赞赏.我正在张贴表.
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(),""});//get size of file
row++;
}
}
}
}
} catch (UnsupportedFlavorException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
} else {
dtde.rejectDrop();
}
}
});
add(scroll,BorderLayout.CENTER);
}
}
}
解决方法
这是一个基本的例子,它基本上使用SwingWorker扫描驱动器的根目录并列出所有文件.一旦完成,它将尝试读取每个文件,在它自己的SwingWorker更新表,因为它.
免责声明：这是一个例子.我使用Thread.sleep轻轻地减慢读取,忽略缓冲区和其他一些事情,我会在生产代码中做不同的,但我想强调进度更新.
怎么运行的
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自定义JProgressBar,但你可能会喜欢一些更复杂的东西.
您需要一些方法来更新表模型.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相关行.然后我使用setValueAt方法来更新行对象.这不是真正需要的,但是我想演示使用setValueAt方法,您可以直接从updateStatus方法更新行对象.
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;
}
}
}
重要概念.
永远,EVER阻止任何长时间运行的事件调度线程.相反,将这些耗时的操作移动到后台线程中.在这里,我使用了SwingWorker
阅读Concurrency in Swing了解更多信息
