{
* This Source Code Form is subject to the terms of the Mozilla Public License,
* v. 2.0. If a copy of the MPL was not distributed with this file, You can
* obtain one at http://mozilla.org/MPL/2.0/
*
* Copyright (C) 2008-2012, Peter Johnson (www.delphidabbler.com).
*
* $Rev$
* $Date$
*
* Implements a dialogue box that gets a single line string of text from user.
}
unit FmEditTextDlg;
interface
uses
// Delphi
StdCtrls, Controls, ExtCtrls, Classes,
// Project
FmGenericOKDlg, UBaseObjects;
type
{
TEditTextDlg:
Dialog box that prompts for and gets a single line string of text from user.
}
TEditTextDlg = class(TGenericOKDlg, INoPublicConstruct)
lblPrompt: TLabel;
edText: TEdit;
procedure btnOKClick(Sender: TObject);
public
type
// Type of anonymous method used to validate entry in edit box
TValidator = reference to function(const Name: string;
out ErrMsg: string): Boolean;
strict private
fValidator: TValidator; // Reference to validator anonymous method
strict protected
procedure InitForm; override;
{Sets focus on edit control.
}
public
class function Execute(const AOwner: TComponent;
const ATitle, APrompt: string; var AText: string;
const AHelpKeyword: string = ''): Boolean; overload;
{Displays dialog box to get requested text from user. Text is not
validated.
@param AOwner [in] Reference to component that owns the dialog box.
@param ATitle [in] Title to be displayed in dialog box caption.
@param APrompt [in] Prompt to be displayed in body of dialog box.
@param AText [in] Default text displayed in edit control. [out] text
entered by user if OK pressed, otherwise unchanged.
@param AHelpKeyword [in] Optional help keyword. If provided a help
button is displayed.
@return True if user OKd, False if cancelled.
}
class function Execute(const AOwner: TComponent;
const ATitle, APrompt: string; var AText: string;
const AValidator: TValidator;
const AHelpKeyword: string = ''): Boolean; overload;
{Displays dialog box to get requested text from user. Text is validated
according to provided validator and dialog box will not close until text
validates OK. An error message is displayed when text fails to validate.
@param AOwner [in] Reference to component that owns the dialog box.
@param ATitle [in] Title to be displayed in dialog box caption.
@param APrompt [in] Prompt to be displayed in body of dialog box.
@param AText [in] Default text displayed in edit control. [out] text
entered by user if OK pressed, otherwise unchanged.
@param AValidator [in] Anonymous method used to validate entered text.
Returns true if text is valid. Returns false and provides error
message if text if not valid.
@param AHelpKeyword [in] Optional help keyword. If provided a help
button is displayed.
@return True if user OKd, False if cancelled.
}
end;
implementation
uses
// Project
UMessageBox;
{$R *.dfm}
{ TEditTextDlg }
procedure TEditTextDlg.btnOKClick(Sender: TObject);
{Handles OK button clicks. Validates text. If validation fails error message
is displayed and dialog box remains open. Dialog box closes if text valid.
@param Sender [in] Not used.
}
var
ErrMsg: string; // Error message if validation fails.
begin
if fValidator(edText.Text, ErrMsg) then
ModalResult := mrOK
else
begin
ModalResult := mrNone;
TMessageBox.Error(Self, ErrMsg);
end;
end;
class function TEditTextDlg.Execute(const AOwner: TComponent; const ATitle,
APrompt: string; var AText: string; const AValidator: TValidator;
const AHelpKeyword: string): Boolean;
{Displays dialog box to get requested text from user. Text is validated
according to provided validator and dialog box will not close until text
validates OK. An error message is displayed when text fails to validate.
@param AOwner [in] Reference to component that owns the dialog box.
@param ATitle [in] Title to be displayed in dialog box caption.
@param APrompt [in] Prompt to be displayed in body of dialog box.
@param AText [in] Default text displayed in edit control. [out] text entered
by user if OK pressed, otherwise unchanged.
@param AValidator [in] Anonymous method used to validate entered text.
Returns true if text is valid. Returns false and provides error message if
text if not valid.
@param AHelpKeyword [in] Optional help keyword. If provided a help button is
displayed.
@return True if user OKd, False if cancelled.
}
begin
Assert(Assigned(AValidator));
with InternalCreate(AOwner) do
try
Caption := ATitle;
HelpKeyword := AHelpKeyword;
btnHelp.Visible := AHelpKeyword <> '';
lblPrompt.Caption := APrompt;
edText.Text := AText;
fValidator := AValidator;
Result := ShowModal = mrOK;
if Result then
AText := edText.Text;
finally
Free;
end;
end;
class function TEditTextDlg.Execute(const AOwner: TComponent; const ATitle,
APrompt: string; var AText: string; const AHelpKeyword: string): Boolean;
{Displays dialog box to get requested text from user. Text is not validated.
@param AOwner [in] Reference to component that owns the dialog box.
@param ATitle [in] Title to be displayed in dialog box caption.
@param APrompt [in] Prompt to be displayed in body of dialog box.
@param AText [in] Default text displayed in edit control. [out] text
entered by user if OK pressed, otherwise unchanged.
@param AHelpKeyword [in] Optional help keyword. If provided a help button is
displayed.
@return True if user OKd, False if cancelled.
}
begin
Result := Execute(
AOwner,
ATitle,
APrompt,
AText,
function(const Text: string; out ErrMsg: string): Boolean
begin
// nul validator: always returns true
ErrMsg := '';
Result := True;
end,
AHelpKeyword
);
end;
procedure TEditTextDlg.InitForm;
{Sets focus on edit control.
}
begin
inherited;
edText.SetFocus;
end;
end.
