Question

我正在开发一个应用程序，列出目录中的文件数组，然后允许用户打开/下载列出的任何文件。知道我应该从哪里开始吗？

Answer 1

你可以试试它的代码：

 private class File_Video extends AsyncTask<String, Integer, String> {
    @Override
    protected String doInBackground(String... sUrl) {

        File folders = new File(Environment.getExternalStorageDirectory()
                + "/pathofthefile/");
        folders.mkdirs();

        File file;
        file = new File(Environment.getExternalStorageDirectory()
                + "/pathofthefile/file_video.txt");


        if (!file.exists()) {
            try {
                file.createNewFile();
            } catch (IOException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
        } else {
            file.delete();
            try {
                file.createNewFile();
            } catch (IOException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
        }

        try {
            URL url = new URL(sUrl[0]);
            URLConnection connection = url.openConnection();
            connection.connect();
            // this will be useful so that you can show a typical 0-100%
            // progress bar
            int fileLength = connection.getContentLength();

            // download the file
            InputStream input = new BufferedInputStream(url.openStream());
            OutputStream output = new FileOutputStream(file);

            byte data[] = new byte[1024];
            long total = 0;
            int count;
            while ((count = input.read(data)) != -1) {
                total += count;
                // publishing the progress....
                publishProgress((int) (total * 100 / fileLength));
                output.write(data, 0, count);
            }

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

    }

来自onCreate：

 File_Video downloadFile_video = new File_Video();

    downloadFile_image.execute("http://youvebsite.com/file1.txt");

用于从服务器下载文件的android脚本

1 个答案: