Unreal Editor Component Picker

Concept

Adds a FComponentPicker struct, with which you can pick an existing actor component via a drop-down menu at editor-time and retrieve it in C++/BP at runtime.

This allows for a more Unity-like dependency injection pattern, where component devs don't need to provide any kind of setter method that has to be manually called to inject the dependency.

Table Of Contents

• Supported Engine Version
• Installation
• Development Status
• Usage
  • Picker Property Configuration
  • Picking a Component
  • Retrieving a Component

Supported Engine Version

The plugin was developed for Unreal Engine 5.5+, though it should work for all 5.X versions.

Installation

The best way is to clone this repository as a submodule; that way you can contribute pull requests if you want and more importantly, easily get latest updates. The project should be placed in your project's Plugins folder.

> cd YourProject
> git submodule add https://github.com/gregorhcs/UEComponentPicker
> git add ../.gitmodules
> git commit

Alternatively you can download the ZIP of this repo and place it in YourProject/Plugins/.

Development Status

This plugin is currently in an experimental state. There are some bugs, missing quality of life features and polish. It definitely wasn't battle-tested yet :)

You can see all improvements I'd like to make in the GitHub issues tab, feel free to open new issues. Also, any general feedback and pull-requests are much appreciated!

Usage

Picker Property Configuration

To configure a component picker in Blueprint, add a new ComponentPicker property to a component, expose it to be editable within the owning actor, compile, then set the allowed class in the default value.

To configure a component picker in C++, add a new FComponentPicker property to a component, expose it to be editable within the owning actor, then set the allowed class in the constructor.

class UMyComponent : public UActorComponent
{
    GENERATED_BODY()
    
    UMyComponent()
    {
        MovementComp.SetAllowedClass(
            UCharacterMovementComponent::StaticClass());
    }

    ...
    UPROPERTY(EditAnywhere)
    FComponentPicker MovementComp;
    ...
}

Picking a Component

After having done the setup above, you can add the component to an actor of your choice, and pick another component on the same actor:

In C++:

class AMyActor : public AActor
{
    GENERATED_BODY()
    
    UMyComponent()
    {
        MyComp->MovementComp.Pick(MoverComponent);
    }

    ...
    UPROPERTY()
    UMyComponent* MyComp;
    ...
}

Retrieving a Component

To retrieve a picked component in Blueprint, you can call Get (Component Picker) on the property, and specify the component type that should be returned. The function will return null, if casting fails.

To retrieve a picked component in C++, you can call Get() either with its default, UActorComponent returning version, or its templated variant.

void UMyComponent::SomeFunc()
{
    UActorComponent* AsActorComp = MovementComp.Get(this);
    auto* AsMovementComp = MovementComp.Get<UCharacterMovementComponent>(this);
}