Copy big file from SD card to internal memory on android

Question

I'm new to Android and I want to copy a big file (approx. 2GB) chosen by the user (so I guess it should have permissions by default) to the internal memory. I already have the permissions added in AndroidManifest but I don't know how (and if I need to) use the Android FileProivder . I would also like to know how this process can happen on another thread such that the app is not blocked during the process and it can show the progress.

Answer 1

You could use a foreground service to do this and make sure the process doesn't get interrupted.

Build the service:

public class CopyService extends Service {
  @Override
  public void onCreate() {

  }

  @Override
  public int onStartCommand(final Intent intent, int flags, int startId) {
    // Run the moving code here
    return START_NOT_STICKY;
  }
}

It's important that you launch it as a foreground service (add permission in manifest), so it doesn't get destroyed after some time. You'll be required to add a notification then, which you can use for progress.

Read further on services: https://developer.android.com/guide/components/services

As @blackapps pointed out it would be wise decision to check the permission and only start the service if it's granted. I usually check if the permission is granted, if not I request it, if it is I follow. Then I check for it once again so I can see if the user granted it or not.

Google has a great article on how to request permissions: https://developer.android.com/training/permissions/requesting

How to move the file though? Here is the code I use in my own app:

private static void moveFile(File from, File to) {
  InputStream inputStream;
  OutputStream outputStream;

  try {
    inputStream = new FileInputStream(from);
    outputStream = new FileOutputStream(to);

    byte[] buffer = new byte[1024];

    while (inputStream.read(buffer) > 0) {
      outputStream.write(buffer);
    }

    inputStream.close();
    outputStream.close();

    // You may wish not to do this if you want to keep the original file
    from.delete();

    Log.i(LOG_TAG, "File copied successfully");

  } catch (IOException e) {
    e.printStackTrace();
  }

  // Stop service here
}

The code you'd like to run inside the service should be placed inside onStartCommand()