How to Implement timing and Countdown (time-based flash sales) for Android

In promotions on shopping websites, there is usually a countdown to limit the shopping time or discount time. How can this be achieved?

A similar problem occurs in an android client project. timer and timertask are used at the beginning. Although this method is common, whether there is a better solution in Android is considered, as a result, we have found the following five implementation solutions. In addition, we will introduce how to use countdowntimer for timing.

Effect:

Method 1

Timer and timertask (Java implementation)

public class timerTask extends Activity{       private int recLen = 11;      private TextView txtView;      Timer timer = new Timer();       public void onCreate(Bundle savedInstanceState){          super.onCreate(savedInstanceState);                    setContentView(R.layout.timertask);          txtView = (TextView)findViewById(R.id.txttime);                    timer.schedule(task, 1000, 1000);       // timeTask      }          TimerTask task = new TimerTask() {          @Override          public void run() {               runOnUiThread(new Runnable() {      // UI thread                  @Override                  public void run() {                      recLen--;                      txtView.setText(""+recLen);                      if(recLen < 0){                          timer.cancel();                          txtView.setVisibility(View.GONE);                      }                  }              });          }      };  }  

Method 2
Timertask and handler (without the improved timer)

public class timerTask extends Activity{      private int recLen = 11;      private TextView txtView;      Timer timer = new Timer();       public void onCreate(Bundle savedInstanceState){          super.onCreate(savedInstanceState);           setContentView(R.layout.timertask);          txtView = (TextView)findViewById(R.id.txttime);           timer.schedule(task, 1000, 1000);       // timeTask      }          final Handler handler = new Handler(){          @Override          public void handleMessage(Message msg){              switch (msg.what) {              case 1:                  txtView.setText(""+recLen);                  if(recLen < 0){                      timer.cancel();                      txtView.setVisibility(View.GONE);                  }              }          }      };       TimerTask task = new TimerTask() {          @Override          public void run() {              recLen--;              Message message = new Message();              message.what = 1;              handler.sendMessage(message);          }      };  }  

Method 3

Handler and message (without timertask) public class timertask extends activity {private int reclen = 11; private textview txtview; Public void oncreate (bundle savedinstancestate) {super. oncreate (savedinstancestate); setcontentview (R. layout. timertask); txtview = (textview1_findviewbyid(r.id.txt time); message = handler. obtainmessage (1); // message handler. sendmessagedelayed (message, 1000);} final handler = new handler () {public void handlemessage (Message MSG) {// handle message switch (MSG. what) {Case 1: reclen --; txtview. settext ("" + reclen); If (reclen> 0) {message = handler. obtainmessage (1); handler. sendmessagedelayed (message, 1000); // send message} else {txtview. setvisibility (view. gone) ;}} super. handlemessage (MSG );}};}

Method 4

Handler and thread (do not occupy the UI thread)

public class timerTask extends Activity{      private int recLen = 0;      private TextView txtView;       public void onCreate(Bundle savedInstanceState){          super.onCreate(savedInstanceState);           setContentView(R.layout.timertask);          txtView = (TextView)findViewById(R.id.txttime);                    new Thread(new MyThread()).start();         // start thread      }          final Handler handler = new Handler(){          // handle          public void handleMessage(Message msg){              switch (msg.what) {              case 1:                  recLen++;                  txtView.setText("" + recLen);              }              super.handleMessage(msg);          }      };       public class MyThread implements Runnable{      // thread          @Override          public void run(){              while(true){                  try{                      Thread.sleep(1000);     // sleep 1000ms                      Message message = new Message();                      message.what = 1;                      handler.sendMessage(message);                  }catch (Exception e) {                  }     

Method 5

Handler and runnable (simplest type) public class timertask extends activity {private int reclen = 0; private textview txtview; Public void oncreate (bundle savedinstancestate) {super. oncreate (savedinstancestate); setcontentview (R. layout. timertask); txtview = (textview1_findviewbyid(r.id.txt time); runnable. run ();} handler = new handler (); runnable = new runnable () {@ override public void run () {reclen ++; txtview. settext ("" + reclen); handler. postdelayed (this, 1000 );}};}

Timing and countdown
Method 1, method 2, and method 3 are all countdown
Method 4 and Method 5 are all timing
Both timing and countdown can be implemented using the above method (slightly changed code)

Ui thread comparison
Method 1, method 2, and method 3 are all timing implemented in the UI thread;
Method 4 and Method 5 are separate runnable threads for timing.

Comparison of implementation methods
Method 1 adopts Java implementation, namely, timer and timertask;
Handler message processing is used in the other four methods.

Recommended
If you do not have high requirements on UI thread interaction, you can select methods 2 and 3.
If the UI thread blocking seriously affects the user experience, Method 4 is recommended. Another thread is used separately for timing and other logic processing.

Method 5, combining the advantages of the previous methods, is the simplest