Start background thread on Android

android-background-thread.java

import android.os.Handler;
import android.os.Looper;
import android.os.Message;
import android.view.View;
import android.widget.TextView;


public void startWorker(View v) {
    mThread.start();
}

Handler.Callback uiCallback = new Handler.Callback() {
    @Override
    public boolean handleMessage(Message msg) {
      TextView mTextView = (TextView) findViewById(R.id.mTextView);
      mTextView.setText(msg.obj.toString());
      return false;
    }
};

Handler uiHandler = new Handler(uiCallback);

Thread mThread = new Thread() {
  public void run() {
    Looper.prepare();
    final Handler mHandler = new Handler();
    final Runnable mRunnable = new Runnable() {
      @Override
      public void run() {
        String mString;
        Message message;
        
        mString = generateRandomString();
        message.obj = mString;
        uiHandler.sendMessage(message);
        
        mHandler.postDelayed(this, 1000);
      }
    };
    mHandler.postDelayed(mRunnable, 1000);
    Looper.loop();
  }
};