Unresolved reference: OnImageCompleteCallback

As an AI language model, I cannot access your specific code or programming environment. However, an "Unresolved reference" error typically means that there is a reference to a variable or function that has not been properly defined or imported in the code. In this case, it seems that "OnImageCompleteCallback" is not recognized by the compiler or interpreter.

To resolve this error, you may need to check the spelling and capitalization of the variable or function name, ensure that it is properly defined or imported in the code, and make sure that any necessary dependencies or libraries are properly installed and configured. Alternatively, you may need to provide more context and details about your specific code and programming language in order to receive more specific advice or solutions.