Standard Dialog/Message Boxes

Standard Windows Dialog Boxes

Windows provides a number of standard dialog boxes.

Visual Basic | Delphi | C++ Builder | Java

Visual Basic 6.0

temp = MsgBox(tempStr, vbCritical, "Can Not Create Directory")
temp = MsgBox("Main Text", vbCritical, "Box Caption")

Delphi

Delphi provides several methods to access the Windows standard dialog boxes

ShowMessage	The simplest to use.
ShowMessagePos	Allows control of the box's xy position.
MessageDlg	Provides more control.
MessageDlgPos	Allows control of the box's xy position.
MessageBox	Provides control of caption and buttons

ShowMessage(const Msg: string);
ShowMessagePos(const Msg: string; X, Y: Integer);
MessageDlg(const Msg: string; AType: TMsgDlgType;
           AButtons: TMsgDlgButtons; HelpCtx: Longint): Word;
MessageBox(Text, Caption: PChar; Flags: Word): Integer;

The following provides a function similar to the VisualBasic MsgBox function

function TForm1.MsgBox(text, caption: string; Flags: Word): Integer;
var
  tempCharArray1, tempCharArray2: array[0..300] of Char;
begin
  StrPCopy(tempCharArray1, Copy(text, 0, 299));
  StrPCopy(tempCharArray2, Copy(caption, 0, 299));
  MsgBox := Application.MessageBox(tempCharArray1, tempCharArray2, Flags);
end;

The following code is copied from the Delphi 5 help. Notice that the conversion of Delphi string constants to PChar is automatic - the conversion of string variables is NOT. The flag constants are directly from the Windows MessageBox help (click See Also / MessageBox). This allows one of 4 icons to be displayed as well as a number of different button configurations. To get a list of acceptable choices, with the cursor in the correct spot, press Ctrl-Space and type mb_. :)

if Application.MessageBox(
   'Could not open Table1 exclusively - Try again?',
   'Open Error', 
   MB_OKCANCEL + MB_DEFBUTTON1) <> IDOK then

The following returns user entered text

InputBox	The simplest to use. Has OK and Cancel buttons.
InputQuery	Returns the value and a True/False for OK/Cancel.

C++ Builder

Java

Start with the Sun Dialog Tutorial. (Interestingly, this tutorial says to use "\n" for a newline.)

JOptionPane.showMessageDialog(frame, "Some message");

The following example shows how to select the icon and to specify the text on the buttons.

Object[] options = {"Yes, please",
                    "No way!"};
int n = JOptionPane.showOptionDialog(frame,
    "Would you like green eggs and ham?",  // message
    "A Silly Question",                    // title
    JOptionPane.YES_NO_OPTION,             // how many buttons
    JOptionPane.QUESTION_MESSAGE,          // icon
    null,                                  // used for custom Icon
    options,                               // array of button lables
    options[0]);                           // lable of the default button

Using simple awt technology, Creating a Reusable Message Box discusses how to create standard dialog boxes from Dialog.

Author: Robert Clemenzi - clemenzi@cpcug.org

Standard Windows Dialog Boxes

Visual Basic 6.0

Delphi

C++ Builder

Java

URL: http:// cpcug.org / user / clemenzi / technical / Languages / DialogBoxes.htm