Cast To A Method in Class

Hi Guys,

I am writing a widget that is making images interactable, so it is an UImage on the surface but SCompoundWidget inside. Now I am trying to update my MyImage in the UImage by casting its MyImage.Get() as the SCompoundWidget* to a method which should take the image as I put in the Editor Page. I understand the getter should get its correspounding SImage, but I really need the image to be interactable with Mouse actions and Touch actions. Could anybody please tell me what is the right way to update MyImage after I put in the Editor?

UClass()
class USeqFrames : public UImage
{
GENERATED_BODY()

public:
UPROPERTY(EditAnywhere, BlueprintReadWrite, Category = "Sequential Frames")
          UTexture2D* Textures;

UFUNCTION(BlueprintCallable, BlueprintReadWrite, Category = "Blah")
           void SetTextures(UTexture2D* InTextures){
                     Textures = InTextures;

                         if(MyImage.IsValid()){
                                   //??????
                          }
            }
        .....

}

class SSeqFrames : public SCompoundWidget
{
public:
	SLATE_BEGIN_ARGS(SSeqFrames)
	{}

	SLATE_END_ARGS()

	..............
	

private:

	UTexture2D* Textures;
	..............

public:

	void SetTextures(UTexture2D* InTextures){
               Textures = InTextures;
        }

I really need help about this! Or could you please show me some articles about casting to different UMG and Slate class? Thank you in advance.