Implementing listener in a new thread

Question

i am currently making an android app and tried to implement an event listener on a new thread. This is the implementation of the onCreate method of the main activity :

protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main );

        new Thread(new Runnable() {
            public void run(){
                seek_bar() ;
            }
        }).start();

    }

and the implementation of the seek_bar method :

public void seek_bar()
    {


        seek=(SeekBar)findViewById(R.id.seekBar1) ;

        seek.setOnSeekBarChangeListener(

                new SeekBar.OnSeekBarChangeListener() {
                    @Override
                    public void onProgressChanged(SeekBar seekBar, int progress, boolean fromUser) {
                         //do somework      

                    }

                    @Override
                    public void onStartTrackingTouch(SeekBar seekBar) {
                     //do some work

                    }

                    @Override
                    public void onStopTrackingTouch(SeekBar seekBar) {
                      //do some work
                    }
                }
        ) ;


    }

It works but my question is what could possibly go wrong , and is it a good practice ?