FDelegateInstanceExtras

Navigation

API > API/Runtime > API/Runtime/Core > API/Runtime/Core/Delegates > API/Runtime/Core/Delegates/FDefaultDelegateUserPolicy

Type

typedef IDelegateInstance FDelegateInstanceExtras  
Copy full snippet

typedef IDelegateInstance FDelegateInstanceExtras

References

Remarks

To extend delegates, you should implement a policy struct like this and pass it as the second template argument to TDelegate and TMulticastDelegate. This policy struct containing three classes called:

FDelegateInstanceExtras:

• Must publicly inherit IDelegateInstance.
• Should contain any extra data and functions injected into a binding (the object which holds and is able to invoke the binding passed to FMyDelegate::CreateSP, FMyDelegate::CreateLambda etc.).
• This binding is not available through the public API of the delegate, but is accessible to FDelegateExtras.

FDelegateExtras:

• Must publicly inherit TDelegateBase.
• Should contain any extra data and functions injected into a delegate (the object which holds an FDelegateInstance-derived object, above).
• Public data members and member functions are accessible directly through the TDelegate object.
• Typically member functions in this class will forward calls to the inner FDelegateInstanceExtras, by downcasting the result of a call to GetDelegateInstanceProtected().

FMulticastDelegateExtras:

• Must publicly inherit TMulticastDelegateBase.
• Should contain any extra data and functions injected into a multicast delegate (the object which holds an array of FDelegateExtras-derived objects which is the invocation list).
• Public data members and member functions are accessible directly through the TMulticastDelegate object.