Hi all,

Lately I've been trying to create a package with custom components, which works already on Lazarus Win32, but gets all kinds of errors on Mac OS X, so I created a package from scratch and try to isolate different problems.

I created a new package and saved it as "TestPackage.lpk", added a new component with TWinControl as ancestor type and named it TCommonTest, named the unit NewCtrls and saved the unit as newctrls.pas. I added a new requirement to the package, so that LCL also is required by the new package.

I then manually added a new component to the unit named TComponentTest with TCommonTest as ancestor, and changed the register procedure to only register the last component.

It compiles, and the component is installed, and the component is visible in the tab "New Ctrls" on Lazarus, which is compiled to Carbon.

But when I try to drop the new component on a form (on a new and clean application) it fails saying "Error moving component ComponentTest1:TComponentTest". The new component does not appear on the Object Inspector at first, but clicking on the component tree will make it appear, and I also can select the component on the form - but nothing is added to the unit source, and the application can't run because of Class "TComponentTest" not found, which naturally is caused by nothing was added to the units uses clause.

Manually making the changes to the forms unit will cause the application to raise an exception with the message: "(V)TCarbonWSWinControl.CreateHandle Error:Not implemented - unable to create Carbon win control for ComponentTest1:TComponentTest!"

Does a new component with an ancestor type of TWinControl need special handling, or is it impossible? Or am I doing something totally wrong?

Thanks and best regards,
Normann

-------
//The NewCtrls unit is simple and looks like this:
unit NewCtrls;
{$mode objfpc}{$H+}
interface
uses
  Classes, SysUtils, LResources, Forms, Controls, Graphics, Dialogs;
type
  TCommonTest = class(TWinControl)
  private
  protected
  public
  published
  end;
  TComponentTest = class(TCommonTest)
  private
  protected
  public
  published
  end;
procedure Register;
implementation
procedure Register;
begin
  RegisterComponents('New Ctrls',[TComponentTest]);
end;
end.
-------
//And the package unit looks like this:
unit TestPackage;
interface
uses
  NewCtrls, LazarusPackageIntf;
implementation
procedure Register;
begin
  RegisterUnit('NewCtrls', @NewCtrls.Register);
end;
initialization
  RegisterPackage('TestPackage', @Register);
end.

Hi again,

I moved up an ancestor type of TCustomControl, and it works better - it might be caused by the paint behavior on Carbon, I dunno, but it would be nice to know why :-)

Regards,
Normann

Hi,
each TWinControl descendant needs to have implemented creation of underlying Carbon control. If you want to use generic TWinControl, you have to choose TCustomControl.

Tom

Thanks Tom, it works. It's old Delphi habit, when you can use TWinControl and design a new control from buttom. But TCustomControl is fine, and I'll work with that ;-)

/Normann

Hi all,

Anybody already translated CAStreamBasicDescription successfully?

CAStreamBasicDescription is a class wrapper for AudioStreamBasicDescription record, which is used in API calls like AudioFileGetProperty etc.

I can do basic translations from struct to record, but classes I C++ is new to me.

Regards,
Normann