Use an object in all units.

[Hansvb]

I have a Logging unit with a TLofFile class. In the main form (TFrmMain) I add Logging to uses. In the public part of TFrmMain = class(TForm) I put

Code: Pascal  [Select][+][-]

1.   public
2.     Logging : TLogFile;

Within the main form I can use Logging directly, but if I create a new unit and want to use logging there too, I have to put the main form in the uses and then I can use logging using mainform.Logging.<some procedure>. So in all units I have to add the main form to uses to access Logging. That could certainly be done better.
How can I access the Logging created in the main form in the individual units without adding the main form to the uses? Or where can i create the logging object outzide the main form so all units can access it?

[TRon]

Depends on what/how you log. If your log functions themselves do not use any visual components then you can store it in a separate unit. I use that myself in a simplelog unit that has all the log functions in it. As an alternative you could use a datamodule but that requires you to use the name of the instance of the datamodule class.

It becomes a tad more difficult if you use visual components but that depends on what visual components it depends.


As an example something like:

Code: Pascal  [Select][+][-]

1. unit Hansvblog;
2.  
3. interface
4.  
5. type
6.   TLogfile = ....
7.  
8. var
9.   Logging : TLogfile;
10.  
11. implementation
12.  
13. procedure TLogfile.Foo;
14. begin
15.   < code of function >
16. end;
17.  
18. function TLogFile.Bar;
19. begin
20.   < code of function >
21. end.
22.  
23. initialization
24.   Logging := TLogFile.Create;
25.  
26. finalization
27.   Logging.Free;
28.  
29. end.
30.  

[Hansvb]

Thera are no visual components in the log unit. And it does not use other units.

[TRon]

Thera are no visual components in the log unit. And it does not use other units.

In that case the example as shown should be enough to fulfill your needs. If there are more questions on how the example works then feel free to ask.

[Hansvb]

The example works. I never knew that is was so easy.
I was searching for more documentation of initialization. The only link i found is:

https://wiki.lazarus.freepascal.org/Initialization

[marcov]

FPC parameter -Fa ?