How can I fix 'android.os.NetworkOnMainThreadException'?

The android.os.NetworkOnMainThreadException is a runtime exception that is thrown when an application attempts to perform a networking operation on the main thread. This is not allowed because networking operations can be slow and block the main thread, causing the UI to become unresponsive.

To fix this exception, you need to perform the networking operation in a background thread, rather than on the main thread. You can use a Thread, an AsyncTask, or a HandlerThread to perform the operation in a background thread.

Here's an example of how you can use an AsyncTask to perform a networking operation in the background:

import android.os.AsyncTask;

public class MyAsyncTask extends AsyncTask<Void, Void, Void> {
  @Override
  protected Void doInBackground(Void... params) {
    // Perform the networking operation here
    return null;
  }
}

// Execute the AsyncTask
new MyAsyncTask().execute();

This code creates a new AsyncTask and executes it in the background. The doInBackground method is called in a background thread, and you can perform the networking operation here.

Note that you should also use a try-catch block to handle any exceptions that might be thrown during the networking operation.

I hope this helps! Let me know if you have any other questions.