delphi MDI form without Tmainmenu - delphi

I am trying to work with MDI forms without TMainMenu and call Form2 from speedbutton which on Ttoolbar. when Form2(child) maximized , form header and bordericons disappears.
I want Form2(child) will be maximized under Ttoolbar and header and border icons are visible

This is how MDI works. instead of using MDI you can use a TPanel and set it as Parent for child forms, something like this:
var
FChild: TfrmChild;
begin
FChild := TfrmChild.Create(Self);
FChild.Parent := pnlMain;
FChild.Show;
end;
...

Related

How do I tile MDI children and maintain BorderStyle = bsNone?

I am hoping someone can help
I have created an object that has a form. I instantiate this object during runtime. The user can then instantiate a second (or multiple) object(s) via a menu step. So two child forms now exist in a parent form. Each objects form's BorderStyle is set to none and Style is set to MDIChild during form creation at runtime:
BorderStyle := bsNone;
FormStyle := fsMDIChild;
All fine. Form has no border.
Now I want to tile the two forms created. Menu > click Tile
procedure TMainForm.Tile1Click(Sender: TObject);
begin
Tile;
end;
Now the border re-appears. I need a way to get rid of the border.
I have tried stepping through the collection of objects and explicitly setting the BorderStyle to none:
procedure TMainForm.Tile1Click(Sender: TObject);
var
i: byte;
begin
Tile;
for i := 0 to GraphCollection.Count-1 do
(GraphCollection.Items[i] as TGraphForm).BorderStyle := bsNone;
end;
This does not work.
Does anyone have a workaround that retains the bsNone style after either Tile or Cascade.
You can do this in another way. I do this with Tabset (TTabSet class) without using fsMDIChild(but BorderStyle = bsNone).
You can add a tab for each form you open on TabSet. By clicking any tab, you can activate or show appropriate form. And delete the appropriate tab for any form by closing it. I prepare an example and you can get it from here.
(I miss-understand the question, my answer is about simulating MDITab for MdiChild forms when the FormStyle is fsNormal and not fsMdiChild)

How can I create a Delphi child window that has a main menu?

I am working with a Delphi form that contains a TMainMenu. In a particular situation I want to show this form parented and client-aligned inside another form. This works fine but the main menu of the parented form does not appear. I see a comment in this SO question that states "A child window cannot have a menu". Is there anything that I can do to override this behaviour and make a TMainMenu appear?
An aside: I've only just noticed this because where I have used this principle before, I've been using the Developer Express menu component and this is quite happy to show in a child form.
Later edit:
Using the code from TLama below, this works (but the child menu is not themed, I,e very plain):
This works:
procedure TForm65.FormShow(Sender: TObject);
begin
Winapi.Windows.SetParent(ChildForm.Handle, Handle); // <<<<<<<<
ChildForm.BorderStyle := bsNone;
ChildForm.Align := alClient;
ChildForm.Show;
end;
This code DOES NOT work. Why?
procedure TForm65.FormShow(Sender: TObject);
begin
ChildForm.Parent := Self; // <<<<<<<<<
ChildForm.BorderStyle := bsNone;
ChildForm.Align := alClient;
ChildForm.Show;
end;
MSDN makes this perfectly clear:
A child window has a client area but no other features, unless they are explicitly requested. An application can request a title bar, a window menu, minimize and maximize buttons, a border, and scroll bars for a child window, but a child window cannot have a menu.
This refers to the menu as drawn by Windows itself. If your component custom draws a menu bar, then of course it can have a menu, even if it is a child window.
Your call to SetParent does not make your window into a child window. This is explained in the documentation:
For compatibility reasons, SetParent does not modify the WS_CHILD or WS_POPUP window styles of the window whose parent is being changed. Therefore, if hWndNewParent is NULL, you should also clear the WS_CHILD bit and set the WS_ POPUP style after calling SetParent. Conversely, if hWndNewParent is not NULL and the window was previously a child of the desktop, you should clear the WS_POPUP style and set the WS_CHILD style before calling SetParent.

TPanel as a splash screen in a MDI app

I want to show a TPanel in the middle of a form that is MDI parent for other forms. Some kind of 'splash' form, but not quite. The panel will contain links/buttons/shortcuts from where the user will call misc. functions.
The main requirement is that the TPanel should be placed below the MDI child form(s) when I click the MDI child. However, as it is, the TPanel will ALWAYS stay above the MDI child forms.
Calling Panel.SendToBack will make the panel disappear. How can I do?
You will need to override the Panel's WindowProc so that the panel will always be behind the MDI children e.g.:
TMainForm = class(TForm)
...
private
FPanelWndProc: TWndMethod;
procedure PanelWndProc(var M: TMessage);
end;
procedure TMainForm.FormCreate(Sender: TObject);
begin
Windows.SetParent(Panel1.Handle, ClientHandle);
// Override Panel1 WindowProc
FPanelWndProc := Panel1.WindowProc;
Panel1.WindowProc := PanelWndProc;
end;
procedure TMainForm.FormDestroy(Sender: TObject);
begin
// Restore Panel1 WindowProc
Panel1.WindowProc := FPanelWndProc;
end;
procedure TMainForm.PanelWndProc(var M: TMessage);
var
P: ^WINDOWPOS;
begin
if M.Msg = WM_WINDOWPOSCHANGING then
begin
P := Pointer(M.LParam);
// Always place panel at bottom
P.hwndInsertAfter := HWND_BOTTOM;
end;
FPanelWndProc(M);
end;
Note: To quickly test the code, you can create a MDI application via File -> New -> MDI Application
EDIT: The code above dose infact answers your initial question. If you want your "Panel to behave somehow as a MDI child" (your comment quote), then simply (...hmmmm...) use a MDI Child form. i.e. create a new form with .FormStyle = fsMDIChild, and then use something like:
SetWindowLong(Child.Handle, GWL_STYLE,
GetWindowLong(Child.Handle, GWL_STYLE) and not (WS_BORDER or WS_DLGFRAME or WS_SIZEBOX));
To remove it's border (since simply setting .BorderStyle = bsNone does not work).
Put whatever you need on that form, and it will move above other MDI forms once you click it.
The MDI system works by having a single window that is the parent of all the MDI child windows, known as the client window. That client window is, in turn, a child of the MDI form. The VCL implementation of MDI creates the child window for you. You can gain access to its window handle through the ClientHandle.
Since the client window is a child of the main form, and parents all the MDI forms, the only solution for you is to make this panel part of the client window.
You could take control of the painting of the client window. You can do this by replacing the window proc of the client window with one of your own. You'll also need to handle button clicks etc. But that's pretty messy.
Now, perhaps you could make your panel a child of the client window. But I'm pretty sure that will screw up your MDI, which indeed you confirm to be the case.

detect if the scrollbars of a form are visible in an mdi child

I cannot detect if the scrollbars of a form are visible.
Googleing the Internet shows that the code below should work. Everybody uses it:
function VertScrollBarVisible(WindowHandle: THandle): Boolean;
begin
Result:= (GetWindowlong(WindowHandle, GWL_STYLE) AND WS_VSCROLL) <> 0
end;
I call it like this:
procedure TFrmBaser.Button1Click(Sender: TObject);
begin
if VertScrollBarVisible(MainForm.Handle)
then Caption:= 'visible';
end;
It returns False all the time, even is the scrollbars are visible. They are made visible by some MDI child forms that I drag a bit out of screen.
Delphi 7, Win XP SP3, Themes on
This
It returns False all the time, even is the scrollbars are visible. They are made visible by some MDI child forms that I drag a bit out of screen.
shows that the form you are having problems with is a MDI parent form (FormStyle is fsMDIForm).
MDI parent forms are different from normal forms in that they create a special client window that fills the whole client area of the form, and which manages the MDI child windows / forms. The MDI client window will never be larger than the client area of its parent, so the parent form will never show scrollbars. This explains that the code in your question always returns false.
The scrollbars you see are part of the MDI client window. Modify your code to check the window style of the client window, its handle can be accessed with the ClientHandle property of the MDI parent form:
procedure TFrmBaser.Button1Click(Sender: TObject);
begin
if VertScrollBarVisible(MainForm.ClientHandle) then
Caption := 'visible';
end;
For more information about MDI at the Windows API level see About the Multiple Document Interface on MSDN.
Try this:
function VertScrollBarVisible(Form : TForm) : Boolean;
begin
Result:=(Form.Width-Form.ClientWidth>10)
end;
I'm not sure if it works, but it compares the "available" width of the form against the "total" width of the form (normally they are within 2-3 pixels of each other, but with a scroll bar, the available width should be significantly lower).

Non-Modal Child Window That Allows Mainform To Be Drawn On Top - Delphi

In Delphi (2009 Pro) - I have a main form that can create non-modal child windows. I want whichever form has the focus to draw on top - even if it is the main window that has the focus.
With Delphi 2007/2009 the VCL changed its behavior regarding the parent of a form. In Delphi 1-2006 the parent of a form was the hidden application window (Application.Handle). In Delphi 2007/2009 the parent of a form is the main form and the main form's parent is the desktop.
If you want to change this you can either change the *.dpr line Application.MainFormOnTaskbar to False what gives you the the old behavior back but also makes your application look strange in Vista and Windows 7. Or you can override the virtual CreateParams method in all your non-modal child forms and set the Params.WndParent field to the desktop (HWND_DESKTOP) or the still existing Application.Handle.
type
TMyChildForm = class(TForm)
protected
procedure CreateParams(var Params: TCreateParams); override;
end;
procedure TForm1.CreateParams(var Params: TCreateParams);
begin
inherited CreateParams(Params);
Params.WndParent := Application.Handle;
end;
Multiple windows cannot have the focus at the same time. I assume you meant to say that you want your non-modal child Form to be on top when only the MainForm has focus. Have you tried setting the child Form's FormStyle property to fsStayOnTop yet?

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