java - 在 jDesktopPane 中打开新的 jInternalFrame 时如何关闭以前的 jInternalFrame

Question

我使用 netbeans 在 java 中创建了 MDI(多文档界面)，其中我有两个 jbuttons 和一个 jdesktoppane 所以当点击两个按钮然后两个 jinternalframes 在同一个 jdesktoppane 中打开，所以我想如何在 jdesktoppane 中 打开新的 jinternalframe 时 关闭以前的 jinternalframe ？

检查快照以更好地理解我的问题我想要什么...

第一个jButton代码:

private void jButton1ActionPerformed(java.awt.event.ActionEvent evt) {                                         
      try
      {

       tst t = new tst();
        JInternalFrame internalFrame1 = new JInternalFrame("Test Window1"); 
        internalFrame1.add(t.getContentPane());
        internalFrame1.pack();

        internalFrame1.setVisible(true);
        q.add(internalFrame1);

        internalFrame1.setClosable(true);  

        BasicInternalFrameUI ui = (BasicInternalFrameUI)internalFrame1.getUI();
        Container north = (Container)ui.getNorthPane();
        north.remove(0);
        north.validate();
        north.repaint();

        for(MouseListener listener : ((javax.swing.plaf.basic.BasicInternalFrameUI) internalFrame1.getUI()).getNorthPane().getMouseListeners()){
        ((javax.swing.plaf.basic.BasicInternalFrameUI) internalFrame1.getUI()).getNorthPane().removeMouseListener(listener);
        }

         internalFrame1.setSelected(true);

      }
      catch(Exception ex)
      {
          JOptionPane.showMessageDialog(null, ex);
      }
    }   

第二个按钮代码:

private void jButton2ActionPerformed(java.awt.event.ActionEvent evt) {                                         
        try
        {

        zxy z = new zxy();
        JInternalFrame internalFrame = new JInternalFrame("Test Window2"); 
        internalFrame.add(z.getContentPane());
        internalFrame.pack();
        internalFrame.setSize(570,420);

        internalFrame.setVisible(true);
        q.add(internalFrame);

        internalFrame.setClosable(true);  

        BasicInternalFrameUI ui = (BasicInternalFrameUI)internalFrame.getUI();
        Container north = (Container)ui.getNorthPane();
        north.remove(0);
        north.validate();
        north.repaint();

        for(MouseListener listener : ((javax.swing.plaf.basic.BasicInternalFrameUI) internalFrame.getUI()).getNorthPane().getMouseListeners()){
        ((javax.swing.plaf.basic.BasicInternalFrameUI) internalFrame.getUI()).getNorthPane().removeMouseListener(listener);
        }

         internalFrame.setSelected(true);

        }
      catch(Exception ex)
      {
          JOptionPane.showMessageDialog(null, ex);
      }
    } 

Answer 1

只需在 JInternalFrame 实例上调用 dispose()。

为此，您需要将 JInternalFrame 声明移出该方法，以便我们可以检查该实例是否不是 null(因此存在一个现有实例然后在创建新实例之前在实例上调用 dispose():

JInternalFrame internalFrame1;

private void jButton1ActionPerformed(java.awt.event.ActionEvent evt) {                                         
      try
      {

       if(internalFrame1 !=null) {//make sure its not null
           internalFrame1.dispose();//close the previos internalframe
       }

        tst t = new tst();
        internalFrame1 = new JInternalFrame("Test Window1"); //create new instance of internal frame
        internalFrame1.add(t.getContentPane());
        internalFrame1.pack();

        internalFrame1.setVisible(true);
        q.add(internalFrame1);

        internalFrame1.setClosable(true);  

        BasicInternalFrameUI ui = (BasicInternalFrameUI)internalFrame1.getUI();
        Container north = (Container)ui.getNorthPane();
        north.remove(0);
        north.validate();
        north.repaint();

        for(MouseListener listener : ((javax.swing.plaf.basic.BasicInternalFrameUI) internalFrame1.getUI()).getNorthPane().getMouseListeners()){
        ((javax.swing.plaf.basic.BasicInternalFrameUI) internalFrame1.getUI()).getNorthPane().removeMouseListener(listener);
        }

         internalFrame1.setSelected(true);

      }
      catch(Exception ex)
      {
          JOptionPane.showMessageDialog(null, ex);
      }
    }