Problem with MDIChild, wsMaximized and inheriting Base form...

Here is the problem. I have one form called TfrmBaseForm, which is inherited in all other forms. It is 500x700, fsMDIChild.

Let's say I have TForm1 = class(TfrmBaseForm). The size of TForm1 is 400x600. I put a button in the bottom right corner of the form and set its Anchors - Bottom and Right = True, Top and Left = False;

When I show the form, the button is not visible, because the form shows with some different size. The same problem is if the form is WindowsState = wsMaximized...

I am using D7.
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DarkCore_Connect With a Mentor Commented:
I used too this method. I have a class function in base class ( showForm : TForm ) for all forms. In this functions I call a "bringtofront", "Maximize" and a "Show" method ( in this order ) always. And it shows always correct forms.

The TControl inherited components repaint itself  using the anchors properties when recieving some messages. But i noticed the problem you say in other applications ( but i discovered this "order" of functions )


My function ( in base class ). It limits one form class each time ( you cannot have two childs of the same class )

class function TFrmBase.formShow :  TForm;
  F : TForm;
  i : Integer;
  F := nil;
  //Lock mainform's update
  LockWindowUpdate( Application.MainForm.Handle );
     Searching for the form I want to show
  For i := 0 to Screen.FormCount - 1 do Begin
      if Screen.Forms[i].ClassName = ClassName then Begin
         F := TForm( Screen.Forms[i] );

  (* if doesn't exists, create it *)
  if F = nil then F := Create( Application.MainForm );
  if F.WindowState <> wsMaximized then F.WindowState := wsMaximized;

  (* Unlock mainform's update *)
  LockWindowUpdate( 0 );
  Result := F;

  //Freeing resources
  SetProcessWorkingSetSize(GetCurrentProcess, $FFFFFFFF, $FFFFFFFF);
guess you you should set the top/left and anchor-properties at runtime for this case

meikl ;-)
Ivanov_GAuthor Commented:
DarkCore_, I have method similar to yours, but I use Self.MDIChildren, instead of Screen.Forms.

> guess you you should set the top/left and anchor-properties at runtime for this case
I mean to set the Anchors for every button on the form ???
Well, then your method is in your mainform, not in your mdichild form. with this method you can do something like


and you will create the form if it not exists or show it ( and bring to front ) if is already created. Then, try the sequence for showing it ... have you tried it? I've not any kind of problem with _exactly_ this sequence. I got problems ( not only with buttons, too with unresized panels and unresized PageControls ) time ago, but this works perfect for me.

kretzschmarConnect With a Mentor Commented:
>I mean to set the Anchors for every button on the form ???

you could use a container like tpanel,
there you can set your buttons with the porperties at designtime,
but let be the align of the tpanel to alNone

at runtime (in the formCreate-event) align your container as you need

just a suggestion

meikl ;-)
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