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Unity预设名称“mainCamera”在当前上下文中不存在

unity3d c#

Keith Power · 技术社区 · 6 年前

我得到错误的名字 mainCamera' does not exist in the current context for the line targetpos=(vector2)maincamera.main.screentownorldpoint(input.mouseposition);`。我在寻找答案,但找不到方法来阻止这一切。

using System.Collections;
using System.Collections.Generic;
using UnityEngine;

public class PlayerController : MonoBehaviour {

    float speed = 2f;
    Vector2 targetPos;

    private Rigidbody2D myRigidbody;
    private Animator myAnim;

    private static bool playerExists;
    public GameObject cameraPrefab;

    private void Start()
    {
        myRigidbody = GetComponent<Rigidbody2D>();
        myAnim = GetComponent<Animator>();

        if(!playerExists){
            playerExists = true;
            DontDestroyOnLoad(transform.gameObject);
        } else {
            Destroy(gameObject);
        }

        targetPos = transform.position;

        GameObject mainCamera = (GameObject)Instantiate(cameraPrefab);
    }

    void Update()
    {
        if (Input.GetMouseButtonDown(0))
        {

            targetPos = (Vector2)mainCamera.main.ScreenToWorldPoint(Input.mousePosition);
        }
        if ((Vector2)transform.position != targetPos)
        {
            Move();
        } else {
            myAnim.SetBool("PlayerMoving", false);
        }
    }

1 回复 | 直到 6 年前

Ruzihm aks786 6 年前

你得到了那个特别的错误,因为 mainCamera 是在中定义的局部变量 Start . 它超出了您试图引用它的范围 Update . 您可能打算将它定义为类中的一个字段,因此可以使用 主摄像机 在你班的任何地方。要做到这一点,您应该改为:

// ...

private Rigidbody2D myRigidbody;
private Animator myAnim;

private static bool playerExists;
public GameObject cameraPrefab; 
public GameObject mainCamera; // add this line

private void Start()
{
    myRigidbody = GetComponent<Rigidbody2D>();
    myAnim = GetComponent<Animator>();

    if(!playerExists){
        playerExists = true;
        DontDestroyOnLoad(transform.gameObject);
    } else {
        Destroy(gameObject);
    }

    targetPos = transform.position;

    mainCamera = (GameObject)Instantiate(cameraPrefab); // use mainCamera field
    mainCamera.tag = "MainCamera"; // tell Unity that it is your main camera.
}

// ...

但无论如何, Camera.main 是的静态属性 Camera 类,因此您应该通过 照相机 不管怎样上课。

你应该把这个用在 更新 而是:

targetPos = (Vector2)Camera.main.ScreenToWorldPoint(Input.mousePosition);