Zitat von Juha Manninen <[email protected]>:
Hi
I have been converting EssModel Delphi program, partly as an exercise and
partly because it could develop into a useful program or component.
It is a reverse engineering class diagram tool.
I am facing more problems than expected. This is not related to Delphi
converter in Lazarus but to the manual editing after it.
First, the code uses a trick. It typecast controls like TForm to a local
TCrackControl just to reach the protected TControl.OnMouseDown and such.
type
TCrackControl = class(TControl); // <-- empty local class
var
found: TControl;
cc: TCrackControl;
and later:
// 'found' can be TForm or anything.
cc:=TCrackControl(found); // <-- error
cc.OnMouseDown := ...
It gives 'RunError(219)', and the whole Lazarus may become unstable.
Do you mean the IDE becomes unstable because of a RunError in a
debugged program?
RunError are critical. There is something very wrong in the code (e.g.
dangling poniter, unintialized variable, etc). Please compile with all
checks.
The typecast is actually OK because the controls inherit from TControl and
OnMouseDown is defined there. According to Mattias this system is
even used in
Lazarus itself. In a small test project the same system worked for me, too.
???
Just to make this clear:
I discourage such dirty tricks. It is better to fix the used class.
The program used interfaces heavily, actually in a clever way. I thought they
cause the above problem and changed the code quite much to get rid of
interfaces. No difference, it still doesn't work.
Next problem: I noticed there are TActions defined in a DataModule which is
created in MainForm.OnActivate handler, and the actions are used in form's
menu and button. I thought it causes problems and I copied everything from
DataModule to MainForm. I set the actions carefully like they were before and
now menu items work but open-button does not. The exact same action is
triggered by menuitem but not by button!
So, this refactoring didn't solve any problems but created a new one.
Can you create a small example to reproduce the problem?
And then: before the program closes it writes recent files to registry. It
gives an error when writing a string, although I can find the "reg.xml" file
it wrote. The same thing works in my small test project without errors.
All the program's behavior is defined in project file, pascal source code and
form files. Am I correct?
Yes.
Although the lpi and lpk files are only needed for the compiler parameters.
So, WHAT CAN CAUSE SUCH PROBLEMS? I have used many many hours already trying
to solve this.
Maybe the program worked only by accident.
The program itself is not very important now, I could as well forget it.
I just feel uncomfortable when there are errors which I can't explain.
Besides I am supposed to improve Delphi converter but now I am not even able
to convert a program myself...
My tests happened on Linux, with GTK2 and QT. If someone likes to look at the
code, please do this:
$ git clone git://github.com/JuhaManninen/Pascal.git
It is not big.
A lot of files use windows codepages. Maybe the converter could try to
fix that automatically?
At least it should be easy to verify the MainForm.OpenButton doesn't work
while it should, even though the program hasn't done anything yet.
Mattias
--
_______________________________________________
Lazarus mailing list
[email protected]
http://lists.lazarus.freepascal.org/mailman/listinfo/lazarus
