Initial Knowledge dialog box

Dialogs are divided into: modal and modeless, patterns will mean blocking execution of other threads, indicating the importance of the operation

1. Message dialog box

belong to modal dialog box

Format: public static void Showmessagedialog (Component parentcomponent,string message,string title,int messageType)

parentcomponent specifies where the dialog box is visible, NULL indicates the front of the screen, and not empty indicates that the component is centered in front of the display

message specifies the content, title specifies the dialog box title

MessageType indicates the type of dialog box

Information_message message dialog box

Warning_message warning Dialog box

Error_message error dialog box

Question_message Problem dialog box

Plain_message Simple dialog box

  String str= jtextfield1.gettext ();             String regex= "[a-za-z]+";              if (Str.matches (regex)) {                 Joptionpane.showmessagedialog (this, "121212", "Sasasa", joptionpane.warning_message);             }              Else {                  joptionpane.showmessagedialog (null, "121212", "Sasasa",joptionpane.information _message);                  Jtextfield1.settext (null);             }

Initial Knowledge dialog box