android - 获取内部存储路径以使用MUPDF打开复制的PDF

我使用以下方法将PDF文件从资产文件夹复制到android的内部存储器中。我打算使用MUPDF Reader打开它。在SO上或在Android上获取内部存储位置的任何位置。我只需要从内部存储中打开复制的文件“ Sample.pdf”。请提供帮助。

private void copyAssets() {
        AssetManager assetManager = getAssets();
        String[] files = null;
        try {
            files = assetManager.list("");
        } catch (IOException e) {
            Log.e("tag", "Failed to get asset file list.", e);
        }
        if (files != null) for (String filename : files) {
            InputStream in = null;
            OutputStream out = null;
            try {
              in = assetManager.open(filename);
              File outFile = new File(getExternalFilesDir(null), filename);
              out = new FileOutputStream(outFile);
              copyFile(in, out);
            } catch(IOException e) {
                Log.e("tag", "Failed to copy asset file: " + filename, e);
            }
            finally {
                if (in != null) {
                    try {
                        in.close();
                    } catch (IOException e) {
                        // NOOP
                    }
                }
                if (out != null) {
                    try {
                        out.close();
                    } catch (IOException e) {
                        // NOOP
                    }
                }
            }
        }
    }
    private void copyFile(InputStream in, OutputStream out) throws IOException {
        byte[] buffer = new byte[1024];
        int read;
        while((read = in.read(buffer)) != -1){
          out.write(buffer, 0, read);
        }
    }

我从您的答案中尝试了该方法。我得到以下内容

12-07 12:33:42.425: E/libmupdf(1858): Opening document...
12-07 12:33:42.427: E/libmupdf(1858): error: cannot open null//Sample.pdf
12-07 12:33:42.428: E/libmupdf(1858): error: cannot load document 'null//Sample.pdf'
12-07 12:33:42.429: E/libmupdf(1858): error: Cannot open document: 'null//Sample.pdf'
12-07 12:33:42.429: E/libmupdf(1858): Failed: Cannot open document: 'null//Sample.pdf'
12-07 12:33:42.433: I/System.out(1858): java.lang.Exception: Failed to open null//Sample.pdf

最佳答案

我通过以下方法解决了这个问题
    上下文上下文= getAppContext（）;
    字符串copyPath = copyFileFromAssetsFolderToStorage（context，“ Sample.pdf”，“ Sample.pdf”，context.getExternalFilesDir（null）.getAbsolutePath（））;

Now once you get the copyPath , now you can use content provider to share this file with mupdf reader app.

if (copyPath != null)
{
    File fileToOpen = new File (copyPath);
    Uri uri = Uri.fromFile(fileToOpen);
}

/**
 * Saves a file from assest folder to a path specified on disk (cache or sdcard).
 * @param context
 * @param assestFilePath    : path from assestfolder for which input stream need to called e.g fonts/AdobeSansF2-Regular.otf
 * @param fileName          : file name of that assest
 * @param filePathInStorage : specified path in the storage
 * @return Absolute path of the file after saving it.
 */
public static String copyFileFromAssetsFolderToStorage(Context context, String assestFilePath, String fileName, String filePathInStorage)
{
    AssetManager assetManager = context.getAssets();
    InputStream in = null;
    OutputStream out = null;
    File copyFileDir = null;
    try
    {
        in = assetManager.open(assestFilePath);
        copyFileDir = new File(filePathInStorage, fileName);
        out = new FileOutputStream(copyFileDir);
        copyFile(in, out);
    }
    catch(IOException e)
    {
    }
    finally
    {
        if (in != null)
        {
            try
            {
                in.close();
            }
            catch (IOException e)
            {
            }
        }
        if (out != null)
        {
            try
            {
                out.close();
            }
            catch (IOException e)
            {
            }
        }
    }
    return copyFileDir != null ? copyFileDir.getAbsolutePath() : null;
}
private static void copyFile(InputStream in, OutputStream out) throws IOException
{
    byte[] buffer = new byte[1024];
    int read;
    while((read = in.read(buffer)) != -1)
    {
        out.write(buffer, 0, read);
    }
}