[Java] Dialog 的範例 showInputDialog

參考資料:
https://docs.oracle.com/javase/tutorial/uiswing/components/dialog.html

import javax.swing.JOptionPane;

public class Dialog_001{
    public static void main(String args[]){
        String name = JOptionPane.showInputDialog("Name: ","AVC");
        //第二格就變程預設值, 可以字串也可以整數,試了連浮點數都行
        String message = String.format("Welcome, %s, to me",name);
        JOptionPane.showMessageDialog(null,message);
    }
}
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Icons used by JOptionPane

Icon description	Java look and feel	Windows look and feel
question
information
warning
error

showMessageDialog方法中, 針對不同的用途用不同參數來顯示User要顯示的東西.


 import javax.swing.JOptionPane;

public class Dialog_001{
    public static void main(String args[]){
        String name = JOptionPane.showInputDialog("Name: ","Ha");
        String message = String.format("Input is : %s.",name);
        JOptionPane.showMessageDialog(null,message,"Title",JOptionPane.PLAIN_MESSAGE);
    }
}

showMessageDialog 的第三個和第四個參數,
要就都要有, 不然就都不要有,不然會編譯錯誤:
Dialog_001.java:9: error: no suitable method found for showMessageDialog(<null>,String,String)
        JOptionPane.showMessageDialog(null,message,"Title");
                   ^
    method JOptionPane.showMessageDialog(Component,Object) is not applicable
      (actual and formal argument lists differ in length)
    method JOptionPane.showMessageDialog(Component,Object,String,int) is not applicable
      (actual and formal argument lists differ in length)
    method JOptionPane.showMessageDialog(Component,Object,String,int,Icon) is not applicable
      (actual and formal argument lists differ in length)
1 error

第三個參數代表在按下確定之後,
顯示出來的視窗標題, 不寫的話就只會顯示 Message,
而第四個參數則是表示視窗要用哪種方式顯示.

都沒填就會顯示:








JOptionPane.WARNING_MESSAGE:

JOptionPane.ERROR_MESSAGE:

JOptionPane.PLAIN_MESSAGE:

JOptionPane.INFORMATION_MESSAGE,icon

在這裡 icon是第五個參數,
要使用時要先 import javax.swing.ImageIcon ;
用 ImageIcon icon = new ImageIcon("C:\\Documents\\b.jpg");
在參數部分試圖片檔案的完整路徑,
用過jpg跟png都可以.