Another question about creating components dynamically

[Hansvb]

Hi,

Another question about creating components dynamically.
I create a panel and then a splitter runtime. The spliiter always seems to be placed first and then the panel. eventhough I create the panel first and then the splitter.

How can i place the splitter on the right side of the panel?

[wp]

Set the Left property of the newly added, left-aligned control to a very large value (Parent.Width, 9999, even MaxInt seems to work) -- this makes the control the rightmost control of all left-aligned controls:

Code: Pascal  [Select][+][-]

1. procedure TForm1.Button1Click(Sender: TObject);
2. begin
3.   if Panel2.ControlCount > 0 then
4.     with TSplitter.Create(self) do
5.     begin
6.       Align := alLeft;
7.       Left := MaxInt;
8.       Parent := Panel2;
9.     end;
10.   with TPanel.Create(Self) do
11.   begin
12.     Align := alLeft;
13.     Left := MaxInt;
14.     Parent := Panel2;
15.   end;
16. end;

[Hansvb]

Code: Pascal  [Select][+][-]

1. Left := MaxInt;
2.  

Gives a range check error but 

Code: Pascal  [Select][+][-]

1. Left := 9999;

does the trick.

[Hansvb]

An old post, but I am again encountering the problem that dynamically created components are incorrectly placed on the form.
As an example: a page control with 2 tabs. 5 panels and splitters are created dynamically on both tabs. The panels and splitters are neatly placed in the correct order on the visible tab. On the tab that is not yet visible, the panels are placed in the reverse order. How can you create components in the correct order and place them on a parent component that is not yet visible? 

I found this, but unfortunately it doesn't get me much further.

https://wiki.freepascal.org/Example:_Anchors._How_to_reliably_align_dynamically_created_controls_under_changing_visibility

It's probably something simple but I don't see it. (I have attached an example).

[cdbc]

Hi Hans
Indeed a puzzling situation, without seemingly reason... 
Upon playing with it, I found that this works:

Code: Pascal  [Select][+][-]

1. procedure TForm1.Button1Click(Sender: TObject);
2. begin
3.   PageControl1.ActivePage:= TabSheet1;
4.   BuilPanelsAndSplitters(TabSheet1);
5.   PageControl1.ActivePage:= TabSheet2;
6.   BuilPanelsAndSplitters(TabSheet2);
7.   PageControl1.ActivePage:= TabSheet1;
8. end;

...and at least on my lappy, there's no flicker 
It's as far from elegant, as you can get ...I know 
Regards Benny

[Hansvb]

Hi Benny, That is indeed some kind of workaround. Another would be to reverse the creation order for a non-visible tabsheet. (Not tested). But I hoped it could be done better. I don't understand the difference between a visible and invisible tab. By the way, I'm on Windows, I thought it might be a Windows thing but you are on linux so that's not it.

[jamie]

beginUpdateBounds ?

...
EndUpdateBounds ..etcc

[wp]

In the attachment there is a modification of your project which seems to work. The main point is that a splitter needs to be freely moveable. Therefore, a vertical splitter must not be anchored horizontally, a horizontal splitter likewise. Instead,  the neighboring controls must be anchored to the splitter sides. Another point is that anchoring requires the controls not the be aligned - but a splitter is left-aligned by default, you must set its Align to alNone. And I also noticed that panel widths seem to be reset to zero for the tabs which are not yet shown; moving the command setting the panel width to another place fixes this issue.

[Hansvb]

I stopped for today. Will look at it tomorrow.

[Hansvb]

I built it into my tool. It works well. Thank you.
There is a lot I didn't know yet.

Edit...
I later found out that it only works well if all panels fit within the parent. If you adjust 5 to 15 then something goes wrong. The panels that do not fit "disappear" at the right side

[Hansvb]

What if I put a scrollbox on the last tab (with the 5 panels). The scroll box is then the parent for the panels. The scroll box never seems to become active because the panels always fit.