How to remove the top bar from a resizable form on Windows 10?

Question

I am trying to remove title-bar of a form while keeping the border to have a resizable form. I set the BorderStyle to bsNone and override the CreateParams procedure:

procedure TMainForm.CreateParams(var Params: TCreateParams);
begin
  inherited;
  Params.Style := Params.Style or  WS_BORDER or WS_THICKFRAME;
end;

The only issue I am facing is a white bar on top edge of the form (in win 10):

How can I get rid of this white bar?

Dorkas

I need WS_THICKFRAME to me the form resizable. – Dorkas

Setting the border style to bsNone makes the window not resizable. Explore the bsToolWindow and bsSizeToolWin alternatives. Going down the WinAPI route can prove to be a lot of work. – Deathless

And the form can be moved as well, right? – Notecase

Yes, but moving the form is straight forward using WMNCHitTest. My problem is the white bar at top edge. – Dorkas

@Ron: bsToolWindow or bsSizeToolWin won't remove the tilebar. – Dorkas

Have you considered handling WM_NCPAINT and possibly WM_NCACTIVATE messages, painting the border the same color as your client area bg? I haven't tried with Win 10 (and can't do so right now) – Painless

It's been a while since you asked that but I created a repository with a solution without VCLStyles... Take a look on my repository and if you want I opened a question here too – Rambouillet

Answer 1

Going the win API way will consume a lot of time and can prove to be so hard. If you are willing to go that way I strongly recommend it. But for the current time here is a quick work around to your problem.

Use the VCL Styles by changing the style of the title bar like this

go to Tools-> Bitmap Style Manager and reopen the Windows 10 style (since you want this in windows 10)

Go to Objects-> form->title and change the height to 5.

in your IDE's object inspector uncheck the border Icons and set the caption to ' '.

The result will be a form with a title bar that is so thin, it is a border.

You can further modify the look of the title bar so it looks exactly like the borders.

and see this Vcl.Forms.TFormStyleHook.PaintNC to know exactly how this is done using style Hooks.

Notecase

Answer 2

In Delphi 11, and possibly earlier, you can create a resizable form without a title bar by using the form's CustomTitleBar property:

Enabled=true
Height=0
ShowCaption=false
ShowIcon=false
SystemButtons=false
SystemColors=false
SystemHeight=false

Form.BorderStyle=bsSizeable

Aemia

Answer 3

It is not handled by Delphi on Windows 10! You must use a tweak tool to control the border size inside windows. I used winaero (www.winaero.com) and reduce the window border to 1 and padding to zero.

Mazard

Answer 4

for firemonkey (fmx) users: You can do this via styles.

Samons