java - Android编程(尝试下载文件到系统目录)

Question

亲爱的 stackOverflow 成员，我最近启动了一个名为“RootBox”的新项目，它是一个需要“su”权限的应用程序，我已成功允许应用程序“su”或“root”访问，我正在尝试下载和替换“/system/media 中的系统文件，我已经设置了下载器，但下载进度对话框弹出并关闭，我猜测这是文件无法写入系统目录的结果，并且我已经重新安装了系统在开始下载之前，我已经在互联网上进行了搜索，但无法找到帮助，这就是我来这里的原因。

这是执行下载的 Activity

public static final int DIALOG_DOWNLOAD_PROGRESS = 0;
private Button startBtn;
private ProgressDialog mProgressDialog;

/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.bootmation);
    startBtn = (Button)findViewById(R.id.startBtn);
    startBtn.setOnClickListener(new OnClickListener(){
        public void onClick(View v) {
            startDownload();
            RootTools.remount("/system/", "rw");
        }
    });
}

private void startDownload() {
    String url = "http://www.filehosting.org/file/details/430746/bootanimation.zip";
    new DownloadFileAsync().execute(url);
}
@Override
protected Dialog onCreateDialog(int id) {
    switch (id) {
    case DIALOG_DOWNLOAD_PROGRESS:
        mProgressDialog = new ProgressDialog(this);
        mProgressDialog.setMessage("Downloading file..");
        mProgressDialog.setProgressStyle(ProgressDialog.STYLE_HORIZONTAL);
        mProgressDialog.setCancelable(false);
        mProgressDialog.show();
        return mProgressDialog;
    default:
        return null;
    }
}

类 DownloadFileAsync 扩展 AsyncTask {

@Override
protected void onPreExecute() {
    super.onPreExecute();
    showDialog(DIALOG_DOWNLOAD_PROGRESS);
}

@Override
protected String doInBackground(String... aurl) {
    int count;

try {

URL url = new URL(aurl[0]);
URLConnection conexion = url.openConnection();
conexion.connect();

int lenghtOfFile = conexion.getContentLength();
Log.d("ANDRO_ASYNC", "Lenght of file: " + lenghtOfFile);

InputStream input = new BufferedInputStream(url.openStream());
OutputStream output = new FileOutputStream("/system/media/bootanimation.zip");

byte data[] = new byte[1024];

long total = 0;

    while ((count = input.read(data)) != -1) {
        total += count;
        publishProgress(""+(int)((total*100)/lenghtOfFile));
        output.write(data, 0, count);
    }

    output.flush();
    output.close();
    input.close();
} catch (Exception e) {}
return null;

}
protected void onProgressUpdate(String... progress) {
     Log.d("ANDRO_ASYNC",progress[0]);
     mProgressDialog.setProgress(Integer.parseInt(progress[0]));
}

@Override
protected void onPostExecute(String unused) {
    dismissDialog(DIALOG_DOWNLOAD_PROGRESS);
}

}}

Answer 1

为此，您必须在 list 中允许写入为

 <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />