Question

Open and close MDIChild from the Mainform

Asked by: erwingosepa

I need to open and close a MDICHILD from a button in the MainForm. The toolbutton has style of checked so when I click the button in it should open MDIChild and when the toolbutton is pressed again it closes the same ChildForm. Other childforms created should stay the way they are.
Could you provide some source code

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Asked On
2006-08-31 at 03:30:01ID21973758
Tags

mdichild

,

close

Topic

Delphi Programming

Participating Experts
2
Points
250
Comments
11

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Answers

 

by: ciulyPosted on 2006-08-31 at 03:36:47ID: 17427772

something like this?

object Form1: TForm1
  Left = 192
  Top = 114
  Width = 696
  Height = 480
  Caption = 'Form1'
  Color = clBtnFace
  Font.Charset = DEFAULT_CHARSET
  Font.Color = clWindowText
  Font.Height = -11
  Font.Name = 'MS Sans Serif'
  Font.Style = []
  FormStyle = fsMDIForm
  OldCreateOrder = False
  PixelsPerInch = 96
  TextHeight = 13
  object Panel1: TPanel
    Left = 0
    Top = 0
    Width = 688
    Height = 41
    Align = alTop
    Caption = 'Panel1'
    TabOrder = 0
    object Button1: TButton
      Left = 56
      Top = 8
      Width = 75
      Height = 25
      Caption = 'Button1'
      TabOrder = 0
      OnClick = Button1Click
    end
  end
end

-----------

unit Unit1;

interface

uses
  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
  Dialogs, StdCtrls, ExtCtrls;

type
  TForm1 = class(TForm)
    Panel1: TPanel;
    Button1: TButton;
    procedure Button1Click(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;

var
  Form1: TForm1;

implementation

uses Unit2;

{$R *.dfm}

procedure TForm1.Button1Click(Sender: TObject);
begin
  if form2.WindowState=wsMinimized then form2.WindowState:=wsNormal
                                   else form2.WindowState:=wsMinimized;
end;

end.

----------

create a new project with the main form/pas having the above code and a mdichild form named form2. is this the behaviour you want?

 

by: geobulPosted on 2006-08-31 at 03:37:39ID: 17427776

Hi,

Try this one:

var
  Child: TMDIChild;

procedure TMainForm.CreateMDIChild(const Name: string);
begin
  if Child = nil then begin
    { create a new MDI child window }
    Child := TMDIChild.Create(Application);
    etc... of your code here
  end else begin
    FreeAndNil(Child);
  end;
end;

Regards, Geo

 

by: geobulPosted on 2006-08-31 at 08:24:02ID: 17429734

What's wrong with my code ? Why 'B' grade?

 

by: erwingosepaPosted on 2006-08-31 at 08:28:34ID: 17429782

it didn'y work with Child = nil in my case so I had to change the code with assigned(form)

 

by: ciulyPosted on 2006-08-31 at 08:39:02ID: 17429911

that code looks good to me. but it doesn't do what you asked for out of the box. maybe you just didn't adapted it correctly to your code.
I mean you asked for an open/close form thing, which I gave, but decided to accept geobuls solution which is a create/destroy solution. so as I see it, there is some communication issue here since you asked for something, you were give 2 good solutions, but for some reason none of them were good enough.
anyway, you have a lot of 7 Bs in your history which means that you are not an easy person to satisfy. and that is probably because you don't communicate correctly and fully your problem.

 

by: ciulyPosted on 2006-08-31 at 08:39:30ID: 17429918

read that "7 B's out of 10 from recent history". it's more correct this way :)

 

by: erwingosepaPosted on 2006-08-31 at 08:57:47ID: 17430049

Correct me if I'm wrong B = Good

 

by: geobulPosted on 2006-08-31 at 09:27:36ID: 17430285

It means that you've assigned something to that 'form' using another code (in the beginning of the app, another button, mixing variable 'form' with something else, using that variable for something else, etc.).

 

by: ciulyPosted on 2006-08-31 at 13:03:52ID: 17432102

> Correct me if I'm wrong B = Good

well .. look at it this way:
A-top
B-middle
C-bottom

that means, on a scale from 1 to 10: 5.

if it's good or not .. well, that is not for me to judge, but I am sure that if you would be in the place of the one answering, doing your best to guess what the asker wants, and after all that you get a B and you are sure it's not your fault ...

you should pay more attention to what you ask and how you ask it so that people understand exactly what you need to get done and not how you thought it to be done. there is usually a big difference between the 2.

 

by: erwingosepaPosted on 2006-08-31 at 14:33:55ID: 17432761

how can I correct it?

 

by: ciulyPosted on 2006-08-31 at 14:40:26ID: 17432798

*IF* you feel you need to correct it, then you can ask in community support for this.
but don't get me wrong, if you feel that B is correct then you should leave it as B and maybe just give some more explanations on the reason (valid for future as well).
usually it is a good idea to just try and solve the issue with the help of the expert/s in order to be sure you will award a correct grade AND get your problems solved correctly. also, (since I am here already :) ) if you get to solve the issue yourself without the help of the experts, you should post the solution and ask in community support for a PAQ & refund.

you can read about all these and more in the help (http://www.experts-exchange.com/help.jsp). you probably should too :)

20120131-EE-VQP-002

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