詢問用戶是否想通過JOptionPane的

Question

退出我使用這個代碼，以確認是否要退出或沒有時，他點擊的JFrame紅十字會關閉按鈕（右上角）用戶

Object[] options = {"Quit, My Computing Fellow", "No, I want to Work more"}; 

int Answer = JOptionPane.showOptionDialog(null, "What would you like to do? ","Quit:Continue", JOptionPane.YES_NO_OPTION, JOptionPane.QUESTION_MESSAGE, 
    null, options,options[1]); 
    if(Answer == JOptionPane.YES_OPTION){ 

     System.exit(0); 
    } 
    else if (Answer == JOptionPane.CANCEL_OPTION) { 
     return; 
    } 

但問題是如果用戶點擊了幀關閉的CANCEL_OPTION，但我希望用戶仍然打開幀並且不允許幀關閉。指導我如果我在做錯誤或其他什麼？

Answer 1

我有一個真正的大錯

Object[] options = {"Quit, My Computing Fellow", "No, I want to Work more"}; 

    int Answer = JOptionPane.showOptionDialog(null, "What would you like to do?","Quit:Continue", JOptionPane.YES_NO_OPTION, JOptionPane.QUESTION_MESSAGE, 
null, options,options[1]); 
if(Answer == JOptionPane.YES_OPTION){ 

    System.exit(0); 
} 
else if (Answer == JOptionPane.CANCEL_OPTION) { 
    return; 
} 

很明顯，我有兩個選擇，即YES_NO_OPTION和我打電話，這是一個真正的錯誤，因此CANCEL_OPTION，其他 - 如果應改爲：

else if (Answer == JOptionPane.NO_OPTION) { 
    this.setDefaultCloseOperation(myclassreference.DO_NOTHING_ON_CLOSE); 
} 

此後;它的賓果！我已經搞定了！

Answer 2

只是這樣做：

setDefaultCloseOperation(JFrame.DO_NOTHING_ON_CLOSE); 

Answer 3

你可以嘗試這樣的事情：

import javax.swing.*; 
    import java.awt.event.*; 
    public class MyFrame extends JFrame 
    { 
     public MyFrame() 
     { 
      setTitle("Close Me"); 
      setSize(200,200); 
      setDefaultCloseOperation(JFrame.DO_NOTHING_ON_CLOSE); 
      addWindowListener(new WindowAdapter() 
      { 
        @Override 
        public void windowClosing(WindowEvent evt) 
        { 
         Object[] options = {"Quit, My Computing Fellow", "No, I want to Work more"}; 

         int answer = JOptionPane.showOptionDialog(MyFrame.this, "What would you like to do? ","Quit:Continue", JOptionPane.YES_NO_OPTION, JOptionPane.QUESTION_MESSAGE, 
            null, options,options[1]); 
         if(answer == JOptionPane.YES_OPTION) 
         { 
          System.exit(0); 
         } 
        } 
      }); 
     } 
     public static void main(String st[]) 
     { 
      SwingUtilities.invokeLater(new Runnable() 
      { 
       public void run() 
       { 
        MyFrame mf = new MyFrame(); 
        mf.setVisible(true); 
       } 
      }); 
     } 
    } 

作爲一個方面說明，我建議你堅持使用Java命名約定。例如，變量名永遠不能以大寫字母開頭，類名始終應以大寫字母開頭..等等。看看這裏Code Conventions for the Java Programming Language

Answer 4

嘗試這樣的事：

{ 
... 
yourFrame.setDefaultCloseOperation(close()); 
... 
} 

private int close() { 
if(yourCondition) 
    return JFrame.DO_NOTHING_ON_CLOSE; 
else 
    return JFrame.EXIT_ON_CLOSE; 
}