android thread

package com.hb.adt0303;

import android.app.Activity;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.TextView;


public class Last extends Activity implements Runnable {
    int su1 = 0, su2 = 0, su3 = 0;
    TextView tv1, tv2, tv3;
    Button bt1, bt2, bt3;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_last);

        tv1 = (TextView) findViewById(R.id.msg1);
        tv2 = (TextView) findViewById(R.id.msg2);
        tv3 = (TextView) findViewById(R.id.msg3);

        bt1 = (Button) findViewById(R.id.btnOne);
        bt2 = (Button) findViewById(R.id.btnTwo);
        bt3 = (Button) findViewById(R.id.btnThr);

        bt1.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {

                // tv1.setText("su1="+su1);
                //2초 간격으로 1씩 증가
                //  Thread.sleep(2000);
                Thread th = new Thread(Last.this);
                th.start();
            }
        });


        bt2.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                su2 = su2 + 5;
                tv2.setText("su2=" + su2);
            }
        });

        //3번째 버튼
        bt3.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                su3 = su3 + 10;
                tv3.setText("su3=" + su3);
            }
        });
    }

        public void run() { //run 메소드안에
            while(true) {
              //  su1 = su1 + 1;
              //  tv1.setText("su1=" + su1);
                runOnUiThread(new Runnable() {
                    @Override
                    public void run() {
                          su1 = su1 + 1;
                          tv1.setText("su1=" + su1);
                    }
                });
                try {
                    Thread.sleep(2000);
                } catch (Exception e) {}
            }
        };

}