ファイルを実行中に既にテキストエリアにテキストを表示する方法 - JAVA

Question

プログラムを実行しているときにテキストエリアにテキストをコピー＆ペーストする必要がないようにしようとしています。 text.Myプログラムは通常のテキストをJSONに解析してJavaに変換し、プログラムを起動するときにテキストエリアに通常のテキストを表示しようとしています。私のコード：

のTextAreaコード

private void InputKeyPressed(java.awt.event.KeyEvent evt) {         
    // TODO add your handling code here: 
    String text = "Call me Ishmael. Some years ago-never mind how long precisely-having " 
+ "little or no money in my purse, and nothing particular to interest me on shore, " 
+ "I thought I would sail about a little and see the watery part of the world. " 
+ "It is a way I have of driving off the spleen and regulating the circulation. " 
+ "Whenever I find myself growing grim about the mouth; whenever it is a damp, " 
+ "drizzly November in my soul; whenever I find myself involuntarily pausing before " 
+ "coffin warehouses, and bringing up the rear of every funeral I meet; and especially " 
+ "whenever my hypos get such an upper hand of me, that it requires a strong moral " 
+ "principle to prevent me from deliberately stepping into the street, and methodically " 
+ "knocking people's hats off-then, I account it high time to get to sea as soon as I can. " 
+ "This is my substitute for pistol and ball. With a philosophical flourish Cato throws himself " 
+ "upon his sword; I quietly take to the ship. There is nothing surprising in this. " 
+ "If they but knew it, almost all men in their degree, some time or other, cherish " 
+ "very nearly the same feelings towards the ocean with me. There now is your insular " 
+ "city of the Manhattoes, belted round by wharves as Indian isles by coral reefs-commerce surrounds " 
+ "it with her surf. Right and left, the streets take you waterward."; 

    Input.setText(text); 
} 

私はので、私はちょうどKeyPressedと一緒に行った選択するイベントではわからないでした。では、ファイルを実行しているときにテキストをテキストエリアに表示させるにはどうしたらよいですか？お時間をありがとう:)

Answer 1

このコメントは：

それは空白まだ実行しているときに表示されます。

重要な情報は、あなたのプログラムがSwingイベントスレッドで長時間実行されるコードを実行していることを示唆しており、これによりイベントスレッドが必要な処理GUIの描画（JTextArea内のテキストを含む）、ユーザーとのやりとりなど、さまざまな作業が含まれます。

問題が解決しない場合、解決策はバックグラウンドスレッド内で長時間実行するコードを実行することですが、その際、イベントスレッドのみでGUIを更新するよう注意してください。 SwingWorkerがこれを行うのに役立ちます。例えばSwingWorker Tutorial

：

import java.awt.BorderLayout; 
import java.awt.event.ActionEvent; 
import java.awt.event.KeyEvent; 
import java.util.concurrent.ExecutionException; 
import java.util.concurrent.TimeUnit; 

import javax.swing.*; 

public class RunFile extends JPanel { 
    public static final String TEXT = "Call me Ishmael. Some years ago-never mind how long precisely-having " 
      + "little or no money in my purse, and nothing particular to interest me on shore, " 
      + "I thought I would sail about a little and see the watery part of the world. " 
      + "It is a way I have of driving off the spleen and regulating the circulation. " 
      + "Whenever I find myself growing grim about the mouth; whenever it is a damp, " 
      + "drizzly November in my soul; whenever I find myself involuntarily pausing before " 
      + "coffin warehouses, and bringing up the rear of every funeral I meet; and especially " 
      + "whenever my hypos get such an upper hand of me, that it requires a strong moral " 
      + "principle to prevent me from deliberately stepping into the street, and methodically " 
      + "knocking people's hats off-then, I account it high time to get to sea as soon as I can. " 
      + "This is my substitute for pistol and ball. With a philosophical flourish Cato throws himself " 
      + "upon his sword; I quietly take to the ship. There is nothing surprising in this. " 
      + "If they but knew it, almost all men in their degree, some time or other, cherish " 
      + "very nearly the same feelings towards the ocean with me. There now is your insular " 
      + "city of the Manhattoes, belted round by wharves as Indian isles by coral reefs-commerce surrounds " 
      + "it with her surf. Right and left, the streets take you waterward."; 
    private static final int TXT_AREA_ROWS = 20; 
    private static final int TXT_AREA_COLS = 40; 
    private JTextArea input = new JTextArea(TXT_AREA_ROWS, TXT_AREA_COLS); 

    public RunFile() { 
     // put jtextarea into scrollpane and allow wrapping of words 
     JScrollPane scrollPane = new JScrollPane(input); 
     input.setWrapStyleWord(true); 
     input.setLineWrap(true); 
     input.setFocusable(false); // make the text area not accept user input 

     JPanel bottomButtonPanel = new JPanel(); 
     // add button that initiates long-running code 
     bottomButtonPanel.add(new JButton(new RunFileEvent())); 

     setLayout(new BorderLayout()); 
     add(scrollPane); 
     add(bottomButtonPanel, BorderLayout.PAGE_END); 
    } 

    // ActionListener for button that runs long-running code 
    private class RunFileEvent extends AbstractAction { 
     public RunFileEvent() { 
      super("Run File"); 
      putValue(MNEMONIC_KEY, KeyEvent.VK_R); 
     } 

     @Override 
     public void actionPerformed(ActionEvent e) { 
      input.setText(TEXT); // display the text 
      setEnabled(false); // in activate the button 

      // create the SwingWorker and start it 
      MyWorker myWorker = new MyWorker(this); 
      myWorker.execute(); 
     } 
    } 

    // SwingWorker to run long-running code 
    private class MyWorker extends SwingWorker<Void, Void> { 
     private RunFileEvent runFileEvent; 

     public MyWorker(RunFileEvent runFileEvent) { 
      this.runFileEvent = runFileEvent; // pass button's action into worker 
     } 

     @Override 
     protected Void doInBackground() throws Exception { 
      // simulate a long-running task with a Thread sleep 
      TimeUnit.SECONDS.sleep(4); 
      return null; 
     } 

     @Override 
     protected void done() { 
      // worker has completed its work 
      input.setText(""); // set text area back to empty 
      runFileEvent.setEnabled(true); // re-enable button 
      try { 
       get(); // call this to capture and handle any exceptions thrown by worker 
      } catch (InterruptedException | ExecutionException e) { 
       e.printStackTrace(); 
      } 
     } 
    } 

    private static void createAndShowGui() { 
     JFrame frame = new JFrame("RunFile"); 
     frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); 
     frame.getContentPane().add(new RunFile()); 
     frame.pack(); 
     frame.setLocationRelativeTo(null); 
     frame.setVisible(true); 
    } 

    public static void main(String[] args) { 
     SwingUtilities.invokeLater(() -> createAndShowGui()); 
    } 
}