Java基础----MessageBox的用法

Java中，类似Windows中MessageBox的使用，用到了JOptionPane类。

利用JOptionPane类中的各个static方法生成了各种类型的对话框。这些对话框都是模式对话框。具体的方法有：

ConfirmDialog ---确认对话框，提出问题，由用户来选择回答，对话框有Yes/No按钮；

InputDialog ---提示输入文本的对话框；

MessageDialog -- 仅显示一些信息；

OptionDialog ---组合了以上三个对话框。

函数原型：

int javax.swing.JOptionPane.showConfirmDialog(Component parentComponent, Object message, String title, int optionType) throws HeadlessException

参数：

parentComponent - determines the Frame in which the dialog is displayed; if null, or if the parentComponent has no Frame, a default Frame is used message - the Object to display title - the title string for the dialog optionType - an int designating the options available on the dialog: YES_NO_OPTION, YES_NO_CANCEL_OPTION, or OK_CANCEL_OPTION

返回值：用户选择的按钮(Yes, No, Cancel, OK)

应用实例：

int rc = JOptionPane.showConfirmDialog(null,
                                             "File already exist. Do you want to overwrite?",
                                             "Overwrite file",
                                             JOptionPane.YES_NO_OPTION);

 

函数原型：

 String javax.swing.JOptionPane.showInputDialog(Object message) throws HeadlessException

参数：message - the Object to display

返回值：用户输入的信息

应用实例：

JOptionDialog.showInputDialog("Please input a value");

 

函数原型：

void javax.swing.JOptionPane.showMessageDialog(Component parentComponent, Object message) throws HeadlessException

参数：

parentComponent - determines the Frame in which the dialog is displayed; if null, or if the parentComponent has no Frame, a default Frame is used message - the Object to display

应用实例：

JOptionPane.showMessageDialog(null, "Getting device list failed. Please check the device.");

弹出一个MessageBox，标题为"消息"，内容为"Getting device list failed. Please check the device."，并有一个"确定"按钮。

 

函数原型：

int javax.swing.JOptionPane.showOptionDialog(Component parentComponent, Object message, String title, int optionType, int messageType, Icon icon, Object[] options, Object initialValue) throws HeadlessException

参数：

parentComponent - determines the Frame in which the dialog is displayed; if null, or if the parentComponent has no Frame, a default Frame is used message - the Object to display title - the title string for the dialog optionType - an integer designating the options available on the dialog: DEFAULT_OPTION, YES_NO_OPTION, YES_NO_CANCEL_OPTION, or OK_CANCEL_OPTION messageType - an integer designating the kind of message this is, primarily used to determine the icon from the pluggable Look and Feel: ERROR_MESSAGE, INFORMATION_MESSAGE, WARNING_MESSAGE, QUESTION_MESSAGE, or PLAIN_MESSAGE icon - the icon to display in the dialog options - an array of objects indicating the possible choices the user can make; if the objects are components, they are rendered properly; non- String objects are rendered using their toString methods; if this parameter is null, the options are determined by the Look and Feel initialValue - the object that represents the default selection for the dialog; only meaningful if options is used; can be null

返回值：an integer indicating the option chosen by the user, or CLOSED_OPTION if the user closed the dialog

应用实例：

Object[] options = {"确定", "取消", "帮助"};

int response = JOptionPane.showOptionDialog(null, "这是一个选择对话框", "选项对话框标题", JOptionPane.YES_OPTION, JOptionPane.QUESTION_MESSAGE, null, options, options[0]);

if(response == 0) ... Yes

else if(response == 1) ... Cancel

else if(response == 2) ... Help