CountDownTimer countdown is very simple and practical,

CountDownTimer countdown is very simple and practical,

This is very simple, so the Code has nothing to explain. It is to remember this API.

Public class MainActivity extends AppCompatActivity {

Private TextView textView; private CountDownTimer downTimer; private long time = 100*1000; // The total countdown time ms @ Overrideprotected void onCreate (Bundle savedInstanceState) {super. onCreate (savedInstanceState); setContentView (R. layout. activity_main); textView = (TextView) findViewById (R. id. tv1); initViews ();} private void initViews () {// 1000 indicates that onTick () downTimer = new CountDownTimer (time, 1000) is executed every 1000 ms) {@ Override public void onTick (long millisUntilFinished) {time-= 1000; textView. setText (time/1000 + "") ;}@ Override public void onFinish () {Toast. makeText (MainActivity. this, "ended", Toast. LENGTH_SHORT ). show () ;};} public void doClick (View view) {switch (view. getId () {case R. id. start: downTimer. start (); // start countdown break; case R. id. stop: downTimer. cancel (); // pause break ;}}