How to copy files from 'assets' folder to sdcard?

If anyone else is having the same problem, this is how I did it

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);    }}

Reference : Move file using Java

Based on your solution, I did something of my own to allow subfolders. Someone might find this helpful:

...

copyFileOrDir("myrootdir");

...

private void copyFileOrDir(String path) {    AssetManager assetManager = this.getAssets();    String assets[] = null;    try {        assets = assetManager.list(path);        if (assets.length == 0) {            copyFile(path);        } else {            String fullPath = "/data/data/" + this.getPackageName() + "/" + path;            File dir = new File(fullPath);            if (!dir.exists())                dir.mkdir();            for (int i = 0; i < assets.length; ++i) {                copyFileOrDir(path + "/" + assets[i]);            }        }    } catch (IOException ex) {        Log.e("tag", "I/O Exception", ex);    }}private void copyFile(String filename) {    AssetManager assetManager = this.getAssets();    InputStream in = null;    OutputStream out = null;    try {        in = assetManager.open(filename);        String newFileName = "/data/data/" + this.getPackageName() + "/" + filename;        out = new FileOutputStream(newFileName);        byte[] buffer = new byte[1024];        int read;        while ((read = in.read(buffer)) != -1) {            out.write(buffer, 0, read);        }        in.close();        in = null;        out.flush();        out.close();        out = null;    } catch (Exception e) {        Log.e("tag", e.getMessage());    }}

The solution above did not work due to some errors:

• directory creation did not work
• assets returned by Android contain also three folders: images, sounds and webkit
• Added way to deal with large files: Add extension .mp3 to the file in the assets folder in your project and during copy the target file will be without the .mp3 extension

Here is the code (I left the Log statements but you can drop them now):

final static String TARGET_BASE_PATH = "/sdcard/appname/voices/";private void copyFilesToSdCard() {    copyFileOrDir(""); // copy all files in assets folder in my project}private void copyFileOrDir(String path) {    AssetManager assetManager = this.getAssets();    String assets[] = null;    try {        Log.i("tag", "copyFileOrDir() "+path);        assets = assetManager.list(path);        if (assets.length == 0) {            copyFile(path);        } else {            String fullPath =  TARGET_BASE_PATH + path;            Log.i("tag", "path="+fullPath);            File dir = new File(fullPath);            if (!dir.exists() && !path.startsWith("images") && !path.startsWith("sounds") && !path.startsWith("webkit"))                if (!dir.mkdirs())                    Log.i("tag", "could not create dir "+fullPath);            for (int i = 0; i < assets.length; ++i) {                String p;                if (path.equals(""))                    p = "";                else                     p = path + "/";                if (!path.startsWith("images") && !path.startsWith("sounds") && !path.startsWith("webkit"))                    copyFileOrDir( p + assets[i]);            }        }    } catch (IOException ex) {        Log.e("tag", "I/O Exception", ex);    }}private void copyFile(String filename) {    AssetManager assetManager = this.getAssets();    InputStream in = null;    OutputStream out = null;    String newFileName = null;    try {        Log.i("tag", "copyFile() "+filename);        in = assetManager.open(filename);        if (filename.endsWith(".jpg")) // extension was added to avoid compression on APK file            newFileName = TARGET_BASE_PATH + filename.substring(0, filename.length()-4);        else            newFileName = TARGET_BASE_PATH + filename;        out = new FileOutputStream(newFileName);        byte[] buffer = new byte[1024];        int read;        while ((read = in.read(buffer)) != -1) {            out.write(buffer, 0, read);        }        in.close();        in = null;        out.flush();        out.close();        out = null;    } catch (Exception e) {        Log.e("tag", "Exception in copyFile() of "+newFileName);        Log.e("tag", "Exception in copyFile() "+e.toString());    }}

EDIT: Corrected a misplaced ";" that was throwing a systematic "could not create dir" error.