[Lazarus] TControl.InvalidatePreferredSize loop detected

[Mattias Gaertner]

On Tue, 26 Oct 2010 20:52:13 +1100
John <jszcmpr at netspace.net.au> wrote:

> On 26/10/2010 6:59 PM, Mattias Gaertner wrote:
> > On Tue, 26 Oct 2010 17:17:00 +1100
> > John<jszcmpr at netspace.net.au>  wrote:
> >
> >> Can anyone enlighten me as to the likely cause(es) of a "TControl.InvalidatePreferredSize loop detected" exception, and how one may debug it ?  It is occurring in a frame, if that is significant, and it is the frame that is specified in the exception.  Looking at the code in TControl.InvalidatePreferredSize, it would appear that the frame must not have a parent, but as it is occurring in the form designer, it is difficult to debug.  I think it may not be happening at run time, but as it started happening at  design time while I was in the middle of some "structural changes", it is hard to get a lot of sense out of the program at run time.
> >>
> >> Environment is WinXP SP3,  fpc SVN 16114 Laz SVN 27864.  (But it also occurred on Laz SVN from a few weeks ago)
> > Do you use only standard LCL controls?
> >
> The frame contains a TLabel, a TButtonPanel, a TBitBtn, a couple of 
> TRadioGroups, and some db Controls - TDBGrid, (with defined columns) 
> TDBNavigator,  TDBMemo.  I guess these are all considered standard ?  

Yes.


> I don't think I have used any controls that didn't come with Lazarus in 
> the whole project.

Can you create a bug report with the unit (lfm plus unit, without the
implementation code) ?

Mattias