capnslipp/GameObjectFindComponentExtension.cs

## GameObjectFindComponentExtension.cs
/// @creator: Slipp Douglas Thompson
/// @license: Public Domain per The Unlicense.  See <http://unlicense.org/>.
/// @purpose: More-flexible GO-tree searching for Components by type, configurable via `SearchExtent` enum arg.
/// @why: Because this functionality should be built-into Unity.
/// @usage: Call `this.gameObject.FindComponent<«component-type»>(«SearchExtent-type»);`.
/// @intended project path: Assets/Plugins/UnityEngine Extensions/GameObjectFindComponentExtension.cs
/// @interwebsouce: https://gist.github.com/capnslipp/ac26e38fce770b5c4594

using System;
using UnityEngine;


public static class GameObjectFindComponentExtension
{
	public enum SearchExtent {
		Local = 1,
		Ancestry, // you are part of your own ancestry
		Ancestors, // you are *not* your own ancestor
		Descendantry, // you are part of your own descendantry
		Descendants, // you are *not* your own descendant

		None = 0
	}

	public static Component FindComponent(this GameObject @this,
		Type componentType,
		SearchExtent extent=SearchExtent.Local
	)
	{
		if (@this == null)
			throw new ArgumentNullException("This extension method was called on a null object, which is not allowed.", "@this");

		string failMessageHead = null;
		Component foundComponent = SearchForComponent(@this, componentType, extent, out failMessageHead);

		if (foundComponent == null)
			Debug.LogWarning(failMessageHead+" "+@this.GetType()+".", @this);

		return foundComponent;
	}

	public static ComponentT FindComponent<ComponentT>(this GameObject @this,
		SearchExtent extent=SearchExtent.Local
	) where ComponentT : Component
	{
		return (ComponentT)FindComponent(@this, typeof(ComponentT), extent);
	}


	static Component SearchForComponent(
		GameObject localGameObject,
		Type componentType,
		SearchExtent extent,
		out string failMessageHead
	)
	{
		switch (extent) {
			case SearchExtent.Local:
				return SearchForComponentInLocal(localGameObject, componentType, out failMessageHead);
			case SearchExtent.Ancestry:
				return SearchForComponentInAncestry(localGameObject, componentType, out failMessageHead, skipLocal: false);
			case SearchExtent.Ancestors:
				return SearchForComponentInAncestry(localGameObject, componentType, out failMessageHead, skipLocal: true);
			case SearchExtent.Descendantry:
				return SearchForComponentInDescendantry(localGameObject, componentType, out failMessageHead, skipLocal: false);
			case SearchExtent.Descendants:
				return SearchForComponentInDescendantry(localGameObject, componentType, out failMessageHead, skipLocal: true);

			default:
				failMessageHead = null;
				return null;
		}
	}

	static Component SearchForComponentInLocal(
		GameObject localGameObject,
		Type componentType,
		out string failMessageHead
	)
	{
		Component foundComponent = localGameObject.GetComponent(componentType);

		if (foundComponent != null) {
			failMessageHead = null;
			return foundComponent;
		}
		else {
			failMessageHead = string.Format("No "+componentType+" assigned and unable to find one for this");
			return null;
		}
	}

	static Component SearchForComponentInAncestry(
		GameObject localGameObject,
		Type componentType,
		out string failMessageHead,
		bool skipLocal=false
	)
	{
		Transform searchTransform = localGameObject.transform;
		if (skipLocal)
			searchTransform = localGameObject.transform.parent;

		Component foundComponent = null;
		while (searchTransform != null) {
			foundComponent = searchTransform.GetComponent(componentType);

			if (foundComponent != null)
				break;

			searchTransform = searchTransform.parent;
		}

		if (foundComponent != null) {
			failMessageHead = null;
			return foundComponent;
		}
		else {
			failMessageHead = string.Format("Unable to find a "+componentType+" "+(skipLocal ? "" : "on or ")+"above this");
			return null;
		}
	}

	static Component SearchForComponentInDescendantry(
		GameObject localGameObject,
		Type componentType,
		out string failMessageHead,
		bool skipLocal=false
	)
	{
		failMessageHead = null;

		Component[] foundComponents = localGameObject.GetComponentsInChildren(componentType, includeInactive: true); // actually searches self and all descendents, despite the name
		foreach (Component oneComponent in foundComponents)
		{
			if (oneComponent.gameObject == localGameObject) {
				if (skipLocal)
					continue;
				else
					return oneComponent;
			}
			else { // non-local
				return oneComponent;
			}
		}

		failMessageHead = string.Format("Unable to find a "+componentType+" "+(skipLocal ? "" : "on or ")+"under this");
		return null;
	}
}

## MonoBehaviourPopulateExtension.cs
/// @creator: Slipp Douglas Thompson
/// @license: Public Domain per The Unlicense.  See <http://unlicense.org/>.
/// @purpose: Populates fields at runtime with references to other components with a one-liner.  Use to provide more GO-tree searching capability and better performance (via caching) than GetComponent.
/// @why: Because this functionality should be built-into Unity.
/// @usage: Call `this.PopulateComponentField(ref this.«component-field», «SearchExtent-type»);` inside Awake() for each field to be populated.
/// 	Optionally, create an additional field of type `GameObjectFindComponentExtension.SearchExtent` and pass that into the PopulateComponentField<>() call in order to allow configuring the SerachExtent in the editor.
/// @intended project path: Assets/Plugins/UnityEngine Extensions/MonoBehaviourPopulateExtension.cs
/// @interwebsouce: https://gist.github.com/capnslipp/ac26e38fce770b5c4594

using System;
using UnityEngine;
using SearchExtent=GameObjectFindComponentExtension.SearchExtent;


public static class MonoBehaviourPopulateExtension
{
	public static void PopulateComponentField(this MonoBehaviour @this,
		Type componentType,
		ref Component field,
		SearchExtent extent=SearchExtent.Local,
		bool forceRepopulate=false
	)
	{
		if (@this == null)
			throw new ArgumentNullException("This extension method was called on a null object, which is not allowed.", "@this");

		if (field != null && !forceRepopulate)
			return;

		Component foundComponent = @this.gameObject.FindComponent(componentType, extent);

		if (foundComponent != null)
			field = foundComponent;
	}

	/// It is probably best to call from within Awake (as opposed to OnEnable or Start) so that its values are ready by the time OnEnable and Start happen.
	/// 	Although this means that another script creating this component (via AddComponent) doesn't have a chance to assign values it may know before we wastefully search out values, Unity doesn't provide us many other options—
	/// 		there is no AddComponentDisabled() equivalent, and
	/// 		Awake is our only chance to set these up before OnEnable (which is often used for repeatable setup logic requiring references to be ready).
	/// 	Awake also ensures that this heavy lifting is done synchronously before we render the first frame of a new scene, hopefully avoiding most in-action stutters.
	public static void PopulateComponentField<ComponentT>(this MonoBehaviour @this,
		ref ComponentT field,
		SearchExtent extent=SearchExtent.Local,
		bool forceRepopulate=false
	) where ComponentT : Component
	{
		Component fieldStandin = field;
		PopulateComponentField(@this, typeof(ComponentT), ref fieldStandin, extent, forceRepopulate);
		field = (ComponentT)fieldStandin;
	}
}

## Ω Example MonoBehaviourPopulateExtension.unitypackage

      
          Raw
        
        
              Ω Example MonoBehaviourPopulateExtension.unitypackage
            
          
          View raw
      
  
## Ω example-usage.part-1.edit-mode.png

      
          Raw
        
        
              Ω example-usage.part-1.edit-mode.png
            
          
## Ω example-usage.part-2.play-mode.png

      
          Raw
        
        
              Ω example-usage.part-2.play-mode.png
            
          
## Ω ExampleSomeOtherMB.cs
using UnityEngine;


public class ExampleSomeOtherMB : MonoBehaviour
{
	public int foo = 26;
}

## Ω ExampleUsage.cs
/// @requires `HideInNormalInspector.cs`, from https://gist.github.com/capnslipp/8138106

using UnityEngine;
using SearchExtent=GameObjectFindComponentExtension.SearchExtent;


public class ExampleUsage : MonoBehaviour
{
	public BoxCollider boxCollider;
	[HideInNormalInspector] public SearchExtent boxCollider_SearchExtent = SearchExtent.Local;

	public ExampleSomeOtherMB someOtherMB;
	[HideInNormalInspector] public SearchExtent someOtherMB_SearchExtent = SearchExtent.Descendantry;


	void Awake()
	{
		this.PopulateComponentField(ref this.boxCollider, this.boxCollider_SearchExtent);
		this.PopulateComponentField(ref this.someOtherMB, this.someOtherMB_SearchExtent);
	}


	void Update()
	{
		// @fillin: Do werk here using `this.boxCollider` and `this.someOtherMB`.
	}
}
	/// @creator: Slipp Douglas Thompson
	/// @license: Public Domain per The Unlicense. See <http://unlicense.org/>.
	/// @purpose: More-flexible GO-tree searching for Components by type, configurable via `SearchExtent` enum arg.
	/// @why: Because this functionality should be built-into Unity.
	/// @usage: Call `this.gameObject.FindComponent<«component-type»>(«SearchExtent-type»);`.
	/// @intended project path: Assets/Plugins/UnityEngine Extensions/GameObjectFindComponentExtension.cs
	/// @interwebsouce: https://gist.github.com/capnslipp/ac26e38fce770b5c4594

	using System;
	using UnityEngine;



	public static class GameObjectFindComponentExtension
	{
	public enum SearchExtent {
	Local = 1,
	Ancestry, // you are part of your own ancestry
	Ancestors, // you are not your own ancestor
	Descendantry, // you are part of your own descendantry
	Descendants, // you are not your own descendant

	None = 0
	}

	public static Component FindComponent(this GameObject @this,
	Type componentType,
	SearchExtent extent=SearchExtent.Local
	)
	{
	if (@this == null)
	throw new ArgumentNullException("This extension method was called on a null object, which is not allowed.", "@this");

	string failMessageHead = null;
	Component foundComponent = SearchForComponent(@this, componentType, extent, out failMessageHead);

	if (foundComponent == null)
	Debug.LogWarning(failMessageHead+" "+@this.GetType()+".", @this);

	return foundComponent;
	}

	public static ComponentT FindComponent<ComponentT>(this GameObject @this,
	SearchExtent extent=SearchExtent.Local
	) where ComponentT : Component
	{
	return (ComponentT)FindComponent(@this, typeof(ComponentT), extent);
	}


	static Component SearchForComponent(
	GameObject localGameObject,
	Type componentType,
	SearchExtent extent,
	out string failMessageHead
	)
	{
	switch (extent) {
	case SearchExtent.Local:
	return SearchForComponentInLocal(localGameObject, componentType, out failMessageHead);
	case SearchExtent.Ancestry:
	return SearchForComponentInAncestry(localGameObject, componentType, out failMessageHead, skipLocal: false);
	case SearchExtent.Ancestors:
	return SearchForComponentInAncestry(localGameObject, componentType, out failMessageHead, skipLocal: true);
	case SearchExtent.Descendantry:
	return SearchForComponentInDescendantry(localGameObject, componentType, out failMessageHead, skipLocal: false);
	case SearchExtent.Descendants:
	return SearchForComponentInDescendantry(localGameObject, componentType, out failMessageHead, skipLocal: true);

	default:
	failMessageHead = null;
	return null;
	}
	}

	static Component SearchForComponentInLocal(
	GameObject localGameObject,
	Type componentType,
	out string failMessageHead
	)
	{
	Component foundComponent = localGameObject.GetComponent(componentType);

	if (foundComponent != null) {
	failMessageHead = null;
	return foundComponent;
	}
	else {
	failMessageHead = string.Format("No "+componentType+" assigned and unable to find one for this");
	return null;
	}
	}

	static Component SearchForComponentInAncestry(
	GameObject localGameObject,
	Type componentType,
	out string failMessageHead,
	bool skipLocal=false
	)
	{
	Transform searchTransform = localGameObject.transform;
	if (skipLocal)
	searchTransform = localGameObject.transform.parent;

	Component foundComponent = null;
	while (searchTransform != null) {
	foundComponent = searchTransform.GetComponent(componentType);

	if (foundComponent != null)
	break;

	searchTransform = searchTransform.parent;
	}

	if (foundComponent != null) {
	failMessageHead = null;
	return foundComponent;
	}
	else {
	failMessageHead = string.Format("Unable to find a "+componentType+" "+(skipLocal ? "" : "on or ")+"above this");
	return null;
	}
	}

	static Component SearchForComponentInDescendantry(
	GameObject localGameObject,
	Type componentType,
	out string failMessageHead,
	bool skipLocal=false
	)
	{
	failMessageHead = null;

	Component[] foundComponents = localGameObject.GetComponentsInChildren(componentType, includeInactive: true); // actually searches self and all descendents, despite the name
	foreach (Component oneComponent in foundComponents)
	{
	if (oneComponent.gameObject == localGameObject) {
	if (skipLocal)
	continue;
	else
	return oneComponent;
	}
	else { // non-local
	return oneComponent;
	}
	}

	failMessageHead = string.Format("Unable to find a "+componentType+" "+(skipLocal ? "" : "on or ")+"under this");
	return null;
	}
	}
	/// @creator: Slipp Douglas Thompson
	/// @license: Public Domain per The Unlicense. See <http://unlicense.org/>.
	/// @purpose: Populates fields at runtime with references to other components with a one-liner. Use to provide more GO-tree searching capability and better performance (via caching) than GetComponent.
	/// @why: Because this functionality should be built-into Unity.
	/// @usage: Call `this.PopulateComponentField(ref this.«component-field», «SearchExtent-type»);` inside Awake() for each field to be populated.
	/// Optionally, create an additional field of type `GameObjectFindComponentExtension.SearchExtent` and pass that into the PopulateComponentField<>() call in order to allow configuring the SerachExtent in the editor.
	/// @intended project path: Assets/Plugins/UnityEngine Extensions/MonoBehaviourPopulateExtension.cs
	/// @interwebsouce: https://gist.github.com/capnslipp/ac26e38fce770b5c4594

	using System;
	using UnityEngine;
	using SearchExtent=GameObjectFindComponentExtension.SearchExtent;



	public static class MonoBehaviourPopulateExtension
	{
	public static void PopulateComponentField(this MonoBehaviour @this,
	Type componentType,
	ref Component field,
	SearchExtent extent=SearchExtent.Local,
	bool forceRepopulate=false
	)
	{
	if (@this == null)
	throw new ArgumentNullException("This extension method was called on a null object, which is not allowed.", "@this");

	if (field != null && !forceRepopulate)
	return;

	Component foundComponent = @this.gameObject.FindComponent(componentType, extent);

	if (foundComponent != null)
	field = foundComponent;
	}

	/// It is probably best to call from within Awake (as opposed to OnEnable or Start) so that its values are ready by the time OnEnable and Start happen.
	/// Although this means that another script creating this component (via AddComponent) doesn't have a chance to assign values it may know before we wastefully search out values, Unity doesn't provide us many other options—
	/// there is no AddComponentDisabled() equivalent, and
	/// Awake is our only chance to set these up before OnEnable (which is often used for repeatable setup logic requiring references to be ready).
	/// Awake also ensures that this heavy lifting is done synchronously before we render the first frame of a new scene, hopefully avoiding most in-action stutters.
	public static void PopulateComponentField<ComponentT>(this MonoBehaviour @this,
	ref ComponentT field,
	SearchExtent extent=SearchExtent.Local,
	bool forceRepopulate=false
	) where ComponentT : Component
	{
	Component fieldStandin = field;
	PopulateComponentField(@this, typeof(ComponentT), ref fieldStandin, extent, forceRepopulate);
	field = (ComponentT)fieldStandin;
	}
	}
	using UnityEngine;



	public class ExampleSomeOtherMB : MonoBehaviour
	{
	public int foo = 26;
	}
	/// @requires `HideInNormalInspector.cs`, from https://gist.github.com/capnslipp/8138106

	using UnityEngine;
	using SearchExtent=GameObjectFindComponentExtension.SearchExtent;



	public class ExampleUsage : MonoBehaviour
	{
	public BoxCollider boxCollider;
	[HideInNormalInspector] public SearchExtent boxCollider_SearchExtent = SearchExtent.Local;

	public ExampleSomeOtherMB someOtherMB;
	[HideInNormalInspector] public SearchExtent someOtherMB_SearchExtent = SearchExtent.Descendantry;


	void Awake()
	{
	this.PopulateComponentField(ref this.boxCollider, this.boxCollider_SearchExtent);
	this.PopulateComponentField(ref this.someOtherMB, this.someOtherMB_SearchExtent);
	}


	void Update()
	{
	// @fillin: Do werk here using `this.boxCollider` and `this.someOtherMB`.
	}
	}