Create floating TToolbar at run-time without flicker - delphi

Question

I'm attempting to create a custom TToolbar at run-time that floats over the form (below the control it is associated with).
My issue is that the process of floating and positioning the toolbar at creation creates a hideous flicker where it is initially drawn at the top-left of the monitor before being moved to my desired position on the form.
I cannot find a way to avoid this. Is there a way?
procedure TMainForm.Button3Click(Sender: TObject);
var
newToolbar : TToolbar;
newButton : TToolButton;
begin
newToolbar := TToolbar.Create(Self);
newToolbar.Visible := False;
newToolbar.ManualFloat( Rect( 0, 0, newToolbar.Width, newToolbar.Height ));
newToolbar.Parent := Self;
newToolbar.left := 100;
newToolbar.Top := 100;
newToolbar.ShowCaptions := True;
newButton := TToolButton.Create(Self);
newButton.Parent := newToolbar;
newButton.Caption := 'Test';
newToolbar.Visible := True;
end;
References:
- Create TToolbutton runtime
- toolbutton with action created at runtime
- Delphi - Create a custom TToolBar component

Answer 1

I am a little puzzled with your solution, so I provide my two takes on the subject. Specifically I don't understand why you are using ManualFloat() and few lines later set the parent of the toolbar, which makes it non-floating.
Here is a solution for a floating toolbar, using ManualFloat().
The toolbar is floating above the form in its own temporary TCustomDockForm,
at the given location.
The record needed by ManualFloat() is setup for the final location, thus no flicker in the wrong place, and the control
is immediately correctly positioned.
procedure TForm1.Button3Click(Sender: TObject);
var
newToolbar : TToolbar;
newButton : TToolButton;
p: TPoint;
begin
newToolbar := TToolbar.Create(Self);
// calculate position in screen coordinates for the floating toolbar
p := ClientOrigin;
p.Offset(100, 100);
// and make it floating in final position
newToolbar.ManualFloat( Rect(p.X, p.Y, p.X+NewToolbar.Width, p.Y+newToolbar.Height) );
newToolbar.Visible := False; // really needed ?
// Then create the toolbar buttons
newToolbar.ShowCaptions := True;
newButton := TToolButton.Create(self);
newButton.Parent := newToolbar;
newButton.Caption := 'Test';
newToolbar.Visible := True;
end;
However, since you actually seem to want a non-floating toolbar, that is just
located anywhere you like on the form (and not in the default top of the form),
a better solution is to skip the ManualFloat() altogether and just set the
Align property of the toolbar to alNone. This enables it to be moved anywhere
on the parent form.
procedure TForm1.Button4Click(Sender: TObject);
var
newToolbar : TToolbar;
newButton : TToolButton;
begin
newToolbar := TToolbar.Create(Self);
newToolbar.Align := alNone; // constructor sets it to alTop
newToolbar.Visible := False; // really needed ?
newToolbar.Parent := Self;
newToolbar.Left := 100;
newToolbar.Top := 200;
newToolbar.ShowCaptions := True;
newButton := TToolButton.Create(self);
newButton.Parent := newToolbar;
newButton.Caption := 'Test';
newToolbar.Visible := True; //
end;
This gives you the same appearance as your own code, but omits the ManualFloat().
Finally, an image to show the appearances:
The bottom toolbar is created with Button4Click()

Answer 2

Thanks #TomBrunberg for your suggestion.
What was needed to make it position over the form without any pre-drawing:
Position it off-screen when ManualFloat is called
Set Visible to false after call to ManualFloat (because ManualFloat sets it true)
Revised code:
procedure TMainForm.Button3Click(Sender: TObject);
var
newToolbar : TToolbar;
newButton : TToolButton;
begin
newToolbar := TToolbar.Create(Self);
// Float with off-screen position
newToolbar.ManualFloat( Rect( 0, -200, newToolbar.Width, newToolbar.Height - 200 ));
// Must hide after ManualFloat call, as it resets Visible to true
newToolbar.Visible := False;
// Set parent so we can add buttons, sets props, etc.
newToolbar.Parent := Self;
// Move to desired position over form
newToolbar.left := 100;
newToolbar.Top := 100;
// Add our button content...
newToolbar.ShowCaptions := True;
newButton := TToolButton.Create(Self);
newButton.Parent := newToolbar;
newButton.Caption := 'Test';
// Now we can show it
newToolbar.Visible := True;
end;