如何使用JOptionPane的響應？

Question

這是我第一次使用確認框，請問如何使用它的建議，我想使用用戶輸入的“是或否”，但不確定如何操作嗎？ 如果我想在if語句中引用JOptionPane的輸入，將如何處理？

JOptionPane.showConfirmDialog(null, "Click yes to terminate. ", "TERMINATE SIMULATION?", JOptionPane.YES_NO_OPTION);

謝謝。

Answer 1

像這樣使用它：

   int result = JOptionPane.showConfirmDialog(null, "Click yes to terminate. ", "TERMINATE SIMULATION?", JOptionPane.YES_NO_OPTION);

    if (JOptionPane.YES_OPTION == result) {
                System.out.println("yes");
     } else if (JOptionPane.NO_OPTION == result) {
                System.out.println("No");
     }else{
            System.out.println("Nothing");
    }

還可以在下面找到選項類型並返回值（來自源）：

 /**
     * Type meaning Look and Feel should not supply any options -- only
     * use the options from the <code>JOptionPane</code>.
     */
    public static final int         DEFAULT_OPTION = -1;
    /** Type used for <code>showConfirmDialog</code>. */
    public static final int         YES_NO_OPTION = 0;
    /** Type used for <code>showConfirmDialog</code>. */
    public static final int         YES_NO_CANCEL_OPTION = 1;
    /** Type used for <code>showConfirmDialog</code>. */
    public static final int         OK_CANCEL_OPTION = 2;

    //
    // Return values.
    //
    /** Return value from class method if YES is chosen. */
    public static final int         YES_OPTION = 0;
    /** Return value from class method if NO is chosen. */
    public static final int         NO_OPTION = 1;
    /** Return value from class method if CANCEL is chosen. */
    public static final int         CANCEL_OPTION = 2;
    /** Return value form class method if OK is chosen. */
    public static final int         OK_OPTION = 0;
    /** Return value from class method if user closes window without selecting
     * anything, more than likely this should be treated as either a
     * <code>CANCEL_OPTION</code> or <code>NO_OPTION</code>. */
    public static final int         CLOSED_OPTION = -1;

另外，不要直接對響應值進行int檢查，例如對於NO_OPTION if(1==result) ，請始終使用JoptionPane類中的常量。

Answer 2

如果您想了解更多有關Swing對話框的信息，請查看Swing教程的以下部分，其中將詳細解釋它，並提供許多示例。

• 如何制作對話框

• 創建和顯示簡單對話框