java回到迴圈 - java loop continue



Java框架在while循環期間不能正確顯示 (2)

不知道你想要做的事情的全部程度,你不可能完全準確的答案。

從事物發出的聲音中,您嘗試在事件調度線程的上下文中運行長時間運行的任務。 此線程負責處理重繪請求等。

阻止此線程,防止Swing重新繪製自己。

從我可以告訴,你想使用一個SwingWorker 。 這將允許您在後台線程中執行您的工作,同時將更新重新同步到EDT

以示例更新

我知道你說的不是“想”使用SwingWorker ,但說實話,它只是更簡單和更安全。

import java.awt.BorderLayout;
import java.awt.EventQueue;
import java.awt.GridBagLayout;
import javax.swing.ImageIcon;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.SwingWorker;
import javax.swing.UIManager;
import javax.swing.UnsupportedLookAndFeelException;

public class LongRunningTask {

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

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

                new BackgroundWorker().start();

            }
        });
    }

    public class BackgroundWorker extends SwingWorker<Object, Object> {

        private JFrame frame;

        public BackgroundWorker() {
        }

        // Cause exeute is final :P
        public void start() {
            ImageIcon icon = new ImageIcon(getClass().getResource("/spinner.gif"));
            JLabel label = new JLabel("This might take some time");
            label.setIcon(icon);

            frame = new JFrame("Testing");
            frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
            frame.setLayout(new GridBagLayout());
            frame.add(label);
            frame.pack();
            frame.setLocationRelativeTo(null);
            frame.setVisible(true);

            execute();
        }

        @Override
        protected Object doInBackground() throws Exception {

            System.out.println("Working hard...");
            Thread.sleep(1000 + (((int)Math.round(Math.random() * 5)) * 1000));
            System.out.println("Or hardly working...");

            return null;

        }

        @Override
        protected void done() {
            frame.dispose();
        }

    }
}

這是一個嚴重的問題,我有一個jFrame。 我有一個“主框架”,其中一切都完成了,但是我有另一個框架中的一個GIF圖像(加載,這個圓圈),這是作為一個初始屏幕使用“處理,請稍候” ,但是當我拉過那個框架,我的while循環運行,框架變成空白,沒有任何顯示,直到循環之後。

我假設這是由於while循環消耗計算機資源和“阻止”任何其他進程運行。

請告訴我該怎麼做。

聲明新框架的代碼是標準的,但是我會在下面發布它。

Processing nc = new Processing();
nc.setVisible(true);

這裡是我的完整的代碼,所以你可以看到我試圖達到什麼:

來自第1幀的代碼(Excel Extractor):

Processing nc = new Processing();
    nc.setVisible(true);

    JFileChooser chooser = new JFileChooser();
    chooser.setFileSelectionMode(JFileChooser.DIRECTORIES_ONLY);
    int option = chooser.showOpenDialog(this); // parentComponent must a component like JFrame, JDialog...
    if (option == JFileChooser.APPROVE_OPTION) {
    File selectedFile = chooser.getSelectedFile();
     directory = selectedFile.getAbsolutePath();
     System.out.println(directory);

    }


   //create a input stream for your excel file from which data will be read. 
   DateFormat dateFormat = new SimpleDateFormat("yyyy_MM_dd");
   SimpleDateFormat sdf = new SimpleDateFormat("HHmmss");
   String curdate = dateFormat.format(new Date());
   Calendar cal = Calendar.getInstance();
   cal.getTime();
   String curtime = sdf.format(cal.getTime());
try{

FileInputStream excelSheetInput = new FileInputStream(path);
//POIFSFileSystem myFileSystem = new POIFSFileSystem(excelSheetInput);
    XSSFWorkbook myWorkBook = new XSSFWorkbook(excelSheetInput);
    //get first work sheet in your excel file.
    Sheet sheet = myWorkBook.getSheetAt(0);
    //we will read data in first rows(0) second column(1)
    Iterator<Row> rowIterator = sheet.iterator();
    Row myRow1 = sheet.getRow(0);
    Cell myCell1 = myRow1.getCell(0);
    String header="";
    Iterator<Cell> cellIterator1 = myRow1.cellIterator();
    int rowCount = 0;

    while(cellIterator1.hasNext()) {

                            Cell cell1 = cellIterator1.next();

                            switch(cell1.getCellType()) {
                                case Cell.CELL_TYPE_BOOLEAN:
                                    header = header + "\""+cell1.getBooleanCellValue()+"\"" + ",";
                                    break;
                                case Cell.CELL_TYPE_NUMERIC:
                                    cell1.setCellType(Cell.CELL_TYPE_STRING);
                                     header = header + "\""+cell1.getStringCellValue()+"\""+",";
                                    //System.out.print(cell.getStringCellValue() + "\t\t");
                                    break;
                                case Cell.CELL_TYPE_STRING:
                                    header = header + "\""+cell1.getStringCellValue()+"\""+",";
                                    //System.out.print(cell.getStringCellValue() + "\t\t");
                                    break;
                            }
    }

    Row myRow = sheet.getRow(1);
    Cell myCell= myRow.getCell(0);
    Iterator<Cell> cellIterator;
    String firstCell = myCell.getStringCellValue();
    int count =1;
    String nextCell;
    String Matter = "Matter Number: "+firstCell;
    String num = firstCell;
    System.out.println(Matter);
    fWriter = new FileWriter(new File(directory, num+"_"+curdate+"_"+curtime+".csv"));
    writer = new BufferedWriter(fWriter);
    writer.write(Matter);
    writer.newLine();
    writer.write(header);
    writer.newLine();
    String temp;
    while(rowIterator.hasNext())
    {


        //temp = "" + rowCount;
        //jLabel5.setText(temp);
        myRow = sheet.getRow(count);
        cellIterator = myRow.cellIterator();
        Cell myCell2 = myRow.getCell(0);
        nextCell= myCell2.getStringCellValue();


        if(nextCell.equals(firstCell))
        {

            while(cellIterator.hasNext()) {

                            Cell cell = cellIterator.next();

                            switch(cell.getCellType()) {
                                case Cell.CELL_TYPE_BOOLEAN:
                                    System.out.print(cell.getBooleanCellValue() + "\t\t");
                                    break;
                                case Cell.CELL_TYPE_NUMERIC:
                                    cell.setCellType(Cell.CELL_TYPE_STRING);

                                     System.out.print(cell.getStringCellValue()+",");

                                    //System.out.print(cell.getStringCellValue() + "\t\t");
                                    writer.write(cell.getStringCellValue()+",");
                                    break;
                                case Cell.CELL_TYPE_STRING:
                                    System.out.print(cell.getStringCellValue()+",");
                                    //System.out.print(cell.getStringCellValue() + "\t\t");
                                    writer.write(cell.getStringCellValue()+",");
                                    break;
                            }
                        }
            System.out.println();
            writer.newLine();
            count++;
            rowCount++;



        }
        else
        {          

            writer.close();
            myRow = sheet.getRow(count);
            myCell2= myRow.getCell(0);
            nextCell=myCell2.getStringCellValue();
            firstCell=nextCell;
            Matter = "Matter Number: "+firstCell;
            num = firstCell;
            System.out.println(Matter);
            fWriter = new FileWriter(new File(directory, num+"_"+curdate+"_"+curtime+".csv"));
            writer = new BufferedWriter(fWriter);
            writer.write(Matter);
            writer.newLine();
            writer.write(header);
            writer.newLine();
        }


    }
}
catch (Exception e)
{
}

  try {
    nc.dispose();
    writer.close();
} catch (IOException ex) {
    Logger.getLogger(FileChooser.class.getName()).log(Level.SEVERE, null, ex);
}
}

第二幀代碼(Processing):

private void initComponents() {

    jLabel1 = new javax.swing.JLabel();
    jLabel2 = new javax.swing.JLabel();

    setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE);

    jLabel1.setFont(new java.awt.Font("Tahoma", 1, 14)); // NOI18N
    jLabel1.setText("Processing, Please Wait...");

    jLabel2.setHorizontalAlignment(javax.swing.SwingConstants.CENTER);
    jLabel2.setIcon(new javax.swing.ImageIcon(getClass().getResource("/loading.gif"))); // NOI18N

    javax.swing.GroupLayout layout = new javax.swing.GroupLayout(getContentPane());
    getContentPane().setLayout(layout);
    layout.setHorizontalGroup(
        layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
        .addGroup(layout.createSequentialGroup()
            .addContainerGap()
            .addComponent(jLabel1)
            .addContainerGap(javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE))
        .addComponent(jLabel2, javax.swing.GroupLayout.Alignment.TRAILING, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE)
    );
    layout.setVerticalGroup(
        layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
        .addGroup(layout.createSequentialGroup()
            .addContainerGap()
            .addComponent(jLabel1)
            .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED, javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE)
            .addComponent(jLabel2)
            .addContainerGap())
    );

    pack();
}

您可以使用java.util包中的Timer Class和schedule timertask在一段時間後說2分鐘或任務完成後關閉啟動畫面。

 final Processing nc = new Processing();
 nc.setVisible(true);
 Timer timer = new Timer():
 TimerTask task = new TimerTask() {
      public void run() { 
          nc.setVisible( false );
          // to do disposing nc
      }
 };
 timer.schedule( task, 1000 * 3 ); // dispose the processing frame after 3 minutes




jframe