Unity获取Animator动画播放完成事件

整理了一些在日常经验中处理动画播放完成事件的方法
方法:
1.Dotween配合异步实现
2.状态机计时方法实现
3.原生动画行为方法实现

方法一：Dotween异步方法

using UnityEngine;
using System.Threading.Tasks;
using DG.Tweening;public class PlayerAnimAsync : MonoBehaviour
{private Animator animator;private bool isAnimPlaying = false;void Start(){animator = GetComponent<Animator>();}void Update(){animator = GetComponent<Animator>();// 开始动画if (!isAnimPlaying){StartAttack();}}private async void StartAttack(){isAnimPlaying = true;await AnimationFinish("Attack", 0f);   //等待Attack播放完Debug.Log("Attack播放完了，可以执行Idle");animator.Play("Idle");isAnimPlaying = false;}//AnimationFinish 异步播放动画public async Task AnimationFinish(string animName, float extreTime = 0f){await DOTween.Sequence().AppendCallback(() => animator.Play(animName)).AppendInterval(GetAnimationClipLength(animName) + extreTime).AsyncWaitForCompletion();}//GetAnimationClipLength 获取动画片段时长private float GetAnimationClipLength(string animName){RuntimeAnimatorController ac = animator.runtimeAnimatorController;foreach (AnimationClip clip in ac.animationClips){if (clip.name == animName){return clip.length;}}return 0f;}
}

方法二：状态机计时方法

using UnityEngine;
public class PlayerAnimFSM : MonoBehaviour
{private enum AnimationState {Idle, Attack}private AnimationState currentState;private Animator animator;private float waitAnimTime = 0f;    //动画计时器void Start(){animator = GetComponent<Animator>();}void Update(){CheckState();currentState = currentState switch{AnimationState.Idle => IdleState(),AnimationState.Attack => AttackState(),_ => currentState};}private AnimationState IdleState(){animator.Play("Idle");return AnimationState.Idle;}private AnimationState AttackState(){//播放动画animator.Play("Attack");waitAnimTime += Time.deltaTime;if (waitAnimTime >= animator.GetCurrentAnimatorStateInfo(0).length){//当动画记录时间大于当前正在播放动画的时间时//todo：这里有一个BUG，在animator.Play()的动画需要在下一帧animator.GetCurrentAnimatorStateInfo(0).length才能获取到正确的时间//在这里默认动画长度都会大于1帧所以没太大的问题//正确的做法是参考方法一种的GetAnimationClipLength来获取动画时间waitAnimTime = 0;   //重置动画时间Debug.Log("Attack播放完了，可以执行Idle");return AnimationState.Idle; //转换Idle状态}return AnimationState.Attack; //维持攻击状态}private void CheckState()    //检测状态转换{if (currentState == AnimationState.Attack)  //维持攻击动画不被打断return;if (Input.GetKeyDown(KeyCode.Space)){currentState = AnimationState.Attack;return;}currentState = AnimationState.Idle;}
}

方法三：原生动画行为方法实现
这里需要用到两个脚本PlayerAnimSM和AttackFinish来实现，此处isAnimPlaying借助原生动画行为来复原

using UnityEngine;public class PlayerAnimSM : MonoBehaviour
{private Animator animator;public bool isAnimPlaying = false;void Start(){animator = GetComponent<Animator>();}void Update(){animator = GetComponent<Animator>();// 开始动画if (!isAnimPlaying){StartAttack();}}private void StartAttack(){isAnimPlaying = true;animator.Play("Attack");}
}

AttackFinish脚本借助界面创建步骤如下：
1.在动画器中点击需要传递动画完成事件的动画，点击右下角的Add Behaviour(添加行为)，可以添加Unity预制的脚本
2.使用这个方法需要有动画过渡的方式(此处为AnyState到Idle)，供后续代码中的OnStateExit使用（举例：如果希望有攻击结束到闲置动画的过渡，就需要从攻击动画连线到闲置动画，重点！！！一定要有退出时间，设置0s也没事，但一定要勾选，这里我就使用AnyState过渡过去了，使用AnyState时也一定要勾选退出时间


创建名为AttackFinish 的脚本(这里Unity叫行为)
双击点开这个脚本

using UnityEngine;public class AttackFinish : StateMachineBehaviour
{// OnStateEnter is called when a transition starts and the state machine starts to evaluate this state//override public void OnStateEnter(Animator animator, AnimatorStateInfo stateInfo, int layerIndex)//{//}// OnStateUpdate is called on each Update frame between OnStateEnter and OnStateExit callbacks//override public void OnStateUpdate(Animator animator, AnimatorStateInfo stateInfo, int layerIndex)//{//}//OnStateExit is called when a transition ends and the state machine finishes evaluating this stateoverride public void OnStateExit(Animator animator, AnimatorStateInfo stateInfo, int layerIndex){//在此处将isAnimPlaying重置回falseanimator.GetComponent<PlayerAnimSM>().isAnimPlaying = false;Debug.Log("Attack播放完了");//播放动画结束后的默认动画，我这里设置为idle你可以设置为任意动画但是一定要有过渡，从Attack到Idle的过渡animator.Play("Idle");}// OnStateMove is called right after Animator.OnAnimatorMove()//override public void OnStateMove(Animator animator, AnimatorStateInfo stateInfo, int layerIndex)//{//    // Implement code that processes and affects root motion//}// OnStateIK is called right after Animator.OnAnimatorIK()//override public void OnStateIK(Animator animator, AnimatorStateInfo stateInfo, int layerIndex)//{//    // Implement code that sets up animation IK (inverse kinematics)//}
}

后谈：还有一些诸如动画帧事件的方法没有收录在内。作者总感觉无论哪一个方法都不是特别合适或者顺手，当然无论是用原生还是自己去写，寻找适合自己项目的方法才是最好的。所以作者也会在今后的开发道路上继续学习。