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How to enter a property into a form?

I will try to ask a question a second time. Do not blame me, please.

Situation:

I have a form

TfrmMain = class(TForm)
private
   [Inject('IniFileSettings')]
   FSettings: ISettings;
public
end;

I have a container initialization procedure:

procedure BuildContainer(const container: TContainer);
begin
  container.RegisterType<TIniSettings>.Implements<ISettings>('IniFileSettings');

  container.RegisterType<TfrmMain, TfrmMain>.DelegateTo(
    function: TfrmMain
    begin
      Application.CreateForm(TfrmMain, Result);
    end);

  container.Build;
end;

So, I initialize both TfrmMain and TIniSettings through the container.

in.DPR I have:

begin
  BuildContainer(GlobalContainer);
  Application.Initialize;
  Application.MainFormOnTaskbar := True;
  Application.CreateForm(TfrmMain, frmMain);
  Application.Run;
end.

I also have an assistant for TApplication:

procedure TApplicationHelper.CreateForm(InstanceClass: TComponentClass; var Reference);
var
  locator: IServiceLocator;
begin
  locator := TServiceLocatorAdapter.Create(GlobalContainer);
  if locator.HasService(InstanceClass.ClassInfo) then
    TObject(Reference) := GlobalContainer.Resolve(InstanceClass.ClassInfo).AsObject
  else
    inherited CreateForm(InstanceClass, Reference);
end;

Problem: when I try

procedure TfrmMain.FormCreate(Sender: TObject);
begin
   s := FSettings.ReadString('Connection', 'Server', 'localhost');
end;

I get an AV exception because FSettings is currently NIL.

What is the correct way to get an FSettings object from a container?

UPDATE:

FSettings := GlobalContainer.Resolve<ISettings>;

This line works fine ... Like last time, I have a problem using the [Inject] attribute. Even with a solution from Stefan, I can get this method to work:

How to initialize the main application form in Spring4D GlobalContainer?

+4
1

, HasService, , . :

if container.Kernel.Registry.HasService(...) then  // yeah yeah, I know LoD is crying right now ;)

ServiceLocator GlobalContainer. , , - . ServiceLocator , ServiceLocator. , , ( .

, , . - . FormCreate ( , OnCreate). , TfrmMain, , , . , -, , , .

:

  • FSettings , (, OnShow OnActivate)
  • , , , "" . , .

, , , , , , . , , TComponent, , , , .

+6

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