重新打開JDesktopPane/JFrame上的JInternalFrame

Question

我有問題重新打開我的代碼中的一個JInternalFrame。我在MenuBar選項「Cadastro」 - >「Cadastro deVeículos」中選擇，此操作打開一個屏幕插入車輛。但是，如果我關閉此屏幕並嘗試重新打開它，我再也不能。

下面是我正在使用的兩個代碼。

• 首先，JMain（這是我的JFrame）：

  import java.awt.Color; 
  import java.awt.event.ActionEvent; 
  import java.awt.event.ActionListener; 
  import java.beans.PropertyVetoException; 
  
  import javax.swing.JDesktopPane; 
  import javax.swing.JFrame; 
  import javax.swing.JMenu; 
  import javax.swing.JMenuBar; 
  import javax.swing.JMenuItem; 
  import javax.swing.WindowConstants; 
  import javax.swing.event.InternalFrameListener; 
  
  public class JMain extends JFrame implements ActionListener{ 
  
      /** 
      * Create the panel. 
      */ 
      private JMenuBar menuBar = new JMenuBar(); 
  
      private JMenu firstMenu = new JMenu("Cadastro"); 
      private JMenu secndMenu = new JMenu("Indicadores"); 
      private JMenu thirdMenu = new JMenu("Agendamentos"); 
      private JMenu fourthMenu = new JMenu("Relatórios"); 
  
      private JMenuItem cadVeiculos = new JMenuItem("Cadastro de Veículos"); 
      private JMenuItem cadMotoristas = new JMenuItem("Cadastro de Motoristas"); 
      private JMenuItem cadCargas = new JMenuItem("Cadastro de Cargas"); 
      private JMenuItem newExit = new JMenuItem("Sair"); 
  
      public JDesktopPane jdPane = new JDesktopPane(); 
  
      JCadVeiculos telaCadVeiculos; 
  
  
  
      public static void main (String args []){ 
       JMain jmain = new JMain(); 
      } 
  
      public JMain() { 
       jdPane.setBackground(Color.LIGHT_GRAY); 
       setTitle("Gtrix - Version 0.1"); 
       setSize(600, 500); 
  
       getContentPane().add(jdPane); 
  
       setJMenuBar(menuBar); 
  
       menuBar.add(firstMenu); 
       menuBar.add(secndMenu); 
       menuBar.add(thirdMenu); 
       menuBar.add(fourthMenu); 
  
       firstMenu.add(cadVeiculos); 
       firstMenu.add(cadMotoristas); 
       firstMenu.add(cadCargas); 
       firstMenu.addSeparator(); 
       firstMenu.add(newExit); 
  
       cadVeiculos.addActionListener(this); 
  
       setVisible(true); 
      } 
  
      public void actionPerformed(ActionEvent evt) { 
       if(evt.getSource() == cadVeiculos){ 
        if(telaCadVeiculos == null){ 
         telaCadVeiculos = new JCadVeiculos(this); 
        } 
  
        //telaCadVeiculos.show(); 
        //telaCadVeiculos.setDefaultCloseOperation(JCadVeiculos.DO_NOTHING_ON_CLOSE); 
        jdPane.moveToFront(telaCadVeiculos); 
  
       } 
      } 
  } 
  

和JCadVeiculos（我的JInternalFrame）：

package ui; 

import java.awt.EventQueue; 
import java.awt.Menu; 

import javax.swing.JDesktopPane; 
import javax.swing.JInternalFrame; 

public class JCadVeiculos extends JInternalFrame { 

    private JMain telaPrincipal; 

    /** 
    * Create the frame. 
    */ 
    public JCadVeiculos(JMain telaPrincipal) { 
     super("", true, true, false); 
     setSize(600,500); 
     setTitle("Cadastro de Veículos"); 
     setVisible(true); 

     this.telaPrincipal = telaPrincipal; 
     telaPrincipal.jdPane.add(this); 
    } 

} 

請幫幫我！ :)

Answer 1

您將需要再次進行JInternalFrame可見的，因爲它是「隱藏」，當它被關閉，例如...

public void actionPerformed(ActionEvent evt) { 
    if(evt.getSource() == cadVeiculos){ 
     if(telaCadVeiculos == null){ 
      telaCadVeiculos = new JCadVeiculos(this); 
     } 

     if (!telaCadVeiculos.getParent().equals(jdPane)) { 
      jdPane.add(telaCadVeiculos); 
     } 
     telaCadVeiculos.setVisible(true); 

     //telaCadVeiculos.show(); 
     //telaCadVeiculos.setDefaultCloseOperation(JCadVeiculos.DO_NOTHING_ON_CLOSE); 
     jdPane.moveToFront(telaCadVeiculos); 

    } 
} 

就我個人而言，我覺得...

telaPrincipal.jdPane.add(this); 

在你裏面JCadVeiculos class worrying。您的JCadVeiculos不應該真正在做出關於它如何被使用的決定，我個人不會以這種方式公開顯示組件，因爲這會導致其他開發人員可能被濫用。

爲JDesktopPane管理的責任在於JMain類，應該決定什麼被添加到JDesktopPane當

隨便說。

你可能也想看看Initial Threads，並確保你從事件指派線程