在Android上运行时写入Unity的StreamingAssets文件夹？

Question

所以......我的目标如下:

1. 使用http请求下载.mp4视频.
2. 使用www.bytes和File.WriteAllBytes()将它放在Android APK的StreamingAssets文件夹中.
3. 使用我购买的EasyMovieTexture电影插件在Android设备上播放.

但是,当我尝试写入StreamingAssets文件夹时,我遇到错误,位于以下路径:

jar:file:///data/app/com.catlard.testName-1.apk!/assets/ash.mp4

这也是下面PlaceMovieInStreamingAssets函数中_debugString的第一个值.甚至可以在Android上运行时写入StreamingAssets文件夹吗？这是我用来做这些东西的课程.它在WriteAllBytes调用中停止 - 我知道,因为我在前后放置了print语句,而这就是它停止的地方.

using UnityEngine;
using System.Collections;
using System.IO;

public class StartVideoFromWeb : MonoBehaviour {

    public string _movieFileName;
    public string _movieHTTPLocation;
    private string _debugString;
    private MediaPlayerCtrl _control;
    public float _mbFileSize = 16.7f;
    private string _movieLocationOnDevice;

    private float _prevProg;

    private WWW _movieWWW;

    public float _kbSpeed;
    public float _timeBetweenSpeedMeasurements = 1f;

    // Use this for initialization

    public IEnumerator Start() {

       yield return StartCoroutine("LoadMovie");
       PlaceMovieInStreamingAssets(_movieWWW);
       yield return new WaitForSeconds(.5f);
       //PlayMovieInCtrl(_movieHTTPLocation + _movieFileName);
       PlayMovieInCtrl(_movieLocationOnDevice);

       yield return 0;
    }

    public void PlayMovieInCtrl(string path) {

       _control = GetComponent<MediaPlayerCtrl>();
       _debugString = _movieFileName + " was loaded into Ctrl";
       _control.Load(path);
       renderer.material.mainTexture = _control.GetVideoTexture();
       _control.Play();
       _debugString = "Attempted to play movie at " + path  + ".";

    }

    public void PlaceMovieInStreamingAssets(WWW www) {

       _movieLocationOnDevice = "jar:file://" + Application.dataPath + "!/assets/" + _movieFileName;
       //_movieLocationOnDevice =  Application.persistentDataPath + "/" + _movieFileName;
       _debugString = "Failed to write to path: " + _movieLocationOnDevice;
       File.WriteAllBytes(_movieLocationOnDevice, www.bytes);
       _debugString = "Wrote file to StreamingAssets folder.";
    }

    public IEnumerator MeasureSpeed() {
       yield return new WaitForSeconds(_timeBetweenSpeedMeasurements);
       float tempMeasure = 0;//((_movieWWW.progress - _prevProg) * (_mbFileSize * 1024f)) * (_timeBetweenSpeedMeasurements /Time.deltaTime);
       _prevProg = _movieWWW.progress;
       if(tempMeasure > 0)
         _kbSpeed = Mathf.RoundToInt(tempMeasure);
       StartCoroutine("MeasureSpeed");
    }

    public IEnumerator LoadMovie () {
       string urlString = _movieHTTPLocation + _movieFileName;
       _movieWWW = new WWW(urlString);
       bool isLoaded = false;
       StartCoroutine("MeasureSpeed");

       while(!isLoaded && _movieWWW.error == null) {

         _debugString = "Movie " + Mathf.RoundToInt(_movieWWW.progress * 100f).ToString() + "%";

         if(_kbSpeed > 0)
          _debugString += " @ " + _kbSpeed.ToString() + "kb/sec";

         if(_movieWWW.progress == 1.0)
          isLoaded = true;
         yield return 0;
       }
       StopCoroutine("MeasureSpeed");

       if(_movieWWW.error == null)
         _debugString = "Movie loaded with no errors.";
       else
         _debugString = _movieWWW.error.ToString();

    }

    public void OnGUI() {
       GUI.Label(new Rect(0,0,700,100), _debugString);
       GUI.Label(new Rect(0,30, 400, 100), "Buffered: " + _control.GetCurrentSeekPercent().ToString());
    }
}

Answer 1

艾哈迈德是正确的，它们是只读的。不过，您可以写信给您的Application.persistentDataPath.

我对 MP3 流媒体也做了同样的事情。我编写的以下脚本从互联网（一个 mp3 文件）获取数据，然后将其保存到 persistedDataPath 并写入字节。如果文件已经存在，它将从本地路径而不是 www 中获取。

using UnityEngine;
using System.Collections;
using System.Net;
using System.IO;

public class PlayMusic : MonoBehaviour {
    public string[] songs;
    public string currentSong;
    public WebClient webClient;
    public float Size = 0.0f;
    private int xRand;
    WWW request;
    byte[] fileData;

    IEnumerator loadAndPlayAudioClip(string song) {
        string path = song;
        currentSong = song;
        FileInfo info = new FileInfo(Application.persistentDataPath + "/" + xRand + "_song.mp3");
        if (info.Exists == true) {
            print("file://"+Application.persistentDataPath + "/" + xRand + "_song.mp3 exists");
            path = "file:///" + Application.persistentDataPath + "/" + xRand + "_song.mp3";
        }

        // Start a download of the given URL
        request = new WWW(path);

        yield return request;

            AudioClip audioTrack = request.GetAudioClip(false, true);
            audio.clip = audioTrack;
            audio.Play();
            Destroy(this);

    }
    void Start () {
        xRand = Random.Range(0, 11);
        StartCoroutine(loadAndPlayAudioClip(songs[xRand]));
    }
    // Update is called once per frame
    void Update () {
       print("Size: "+Size+" bytes");
       if (request.isDone) {
               fileData = request.bytes;
               Size = fileData.Length;
               if (fileData.Length > 0) {
                        File.WriteAllBytes(Application.persistentDataPath + "/" + xRand + "_song.mp3", fileData);
                        print("Saving mp3 to " + Application.persistentDataPath + "/" + xRand + "_song.mp3");
                }
       }
    }
}

Answer 2

项目声明(StreamingAssets,RawAssets等)是只读的,你不能在那里写任何东西,而是写写内部/外部存储看看这里,如果你更喜欢用c#写,我相信你会使用Xaramin框架