Using the UPROPERTY macro

The UPROPERTY macro is placed above the definition of standard C++ class variables to declare Unreal-recognized class properties. The UPROPERTY macro can have specifiers and metadata for different use cases.

The UPROPERTY syntax

Let’s take a look at the UPROPERTY syntax:

UPROPERTY([specifier1, specifier2, …], [meta(key1=value, key2=value2, … )]Type VariableName;

Let’s break it down:

• As with function parameters, the specifiers and metadata are enclosed by a pair of parentheses
• The square brackets are used to indicate that the enclosed content is optional
• The ellipsis means that you can include more items
• The metadata keys are only valid in the editor, and not for any game logic

Let’s look at two examples. The first example shows how to define a simple UPROPERTY variable:

UPROPERTY()bool bHasWeapon;

This example defines the bHasWeapon property without any specifiers and metadata...