Как уже отображать текст в текстовом поле при запуске файла - JAVA

Question

Я пытаюсь сделать так, что пользователю не нужно копировать и вставлять текст в текстовое поле при запуске программы, поэтому вместо этого в текстовом поле уже содержится программа text.My анализирует обычный текст в JSON, затем на Java, я пытаюсь сделать обычный текстовый дисплей в текстовом поле при запуске программы. Мой код:

TextArea Код

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); 
} 

Я не был уверен, в этом случае, чтобы выбрать, так что я просто пошел с Keypressed. Итак, как я могу заставить текст уже отображаться в текстовом поле при запуске файла? Спасибо за ваше время :)

Answer 1

Этот комментарий:

он показывает, как пустой еще при запуске.

Это ключевая информация, которую вы должны нам дать, и предлагает, чтобы ваша программа запускала длительный код в потоке событий Swing, и, делая это, вы предотвращаете поток событий от необходимости обязанности, включая рисование GUI - включая текст в JTextArea и взаимодействие с пользователем.

Если это проблема, тогда решение состоит в том, чтобы выполнить длинный код в фоновом потоке, но при этом заботиться о обновлении графического интерфейса только в потоке событий. SwingWorker может помочь вам в этом. SwingWorker Tutorial

Например:

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()); 
    } 
}