Custom component TAction (s) - OnExecute overide

[Stano 143]

I always create all Actions only once. They live during the life of the instance.

I define an OnExecute event in the component and, if necessary, at design time in the instance
I want this behavior on the runtime:

• if the event is only in the component, it will not always exist, so it will be triggered
• if the event is only in the instance, it will fire
• if the event is in the component as well as in the instance, then the event in the instance is triggered first and the event in the component is called with inherited

Classic behavior

About component

  TjstVstDBNavigator = class(TCustomActionToolBar)
  strict private
    FAcnMan: TAcTionManager;

Current status

• In the component, I assign an Action OnExecute to each. As a result
• Logically, only the event in the component always fires
• Event in the instance will never run

Edited April 11, 2022 by Stano

[Stano 143]

I did not write that events must have access to component fields. Otherwise they are worthless.

[Stano 143]

I found out it could also be a Button.OnClick. Which is easier.

[David Heffernan 2345]

5 hours ago, Stano said:

I want this behavior on the runtime:

• if the event is only in the component, it will not always exist, so it will be triggered
• if the event is only in the instance, it will fire
• if the event is in the component as well as in the instance, then the event in the instance is triggered first and the event in the component is called with inherited

I cannot understand what you mean by event in component or instance. In fact I can't make any sense out of this. 

[Stano 143]

In component - code written hard during component design. E.g. DataSource.Post itself
In the instance - a component on the form and it is necessary to extend the event. E.g. for DataSource.Post do the data check first

Edited April 11, 2022 by Stano

[Stano 143]

I think I've found a solution

  TjstVstDBNavigator = class(TCustomActionToolBar)
  type
  Ta = class(TAction)
  private
    bb: TjstVstDBNavigator;
  public
    constructor Create(AOwner: TComponent); override;
  end;

constructor TjstVstDBNavigator.Ta.Create(AOwner: TComponent);
begin
  inherited;
  bb := TjstVstDBNavigator(Owner);
  bb.AcnMan;  // It knows AcnMan
end;

This is a principle. Now I can override the event. I believe it will work.

[Stano 143]

Premature joy. I forgot that OnExecute is a property!

[Attila Kovacs 629]

8 minutes ago, Stano said:

Premature joy. I forgot that OnExecute is a property!

There is always a virtual DoXY behind the OnXY.

[Stano 143]

If he overrides it, will it work for me normally? That would make me very happy.