How to set a timer in Android Studio to perform tasks at constant intervals?
I am developing a simple application with Android Studio and I need to create a timer to run some methods every 1 second.
I tried the following way but it didn't work:
int delay = 1000;
int interval = 1000;
Timer timer = new Timer();
timer.scheduleAtFixedRate(new TimerTask() {
public void run() {
// métodos ...
}
}, delay, interval);
When the timer is activated for the first time, fatal error occurs closing the application.
3 answers
I strongly recommend that you use the Class Handler because on android, any process that is a little time consuming and that is not in a Thread will be considered a crash and will be terminated with a critical error. Not sure, but as far as I know the Times class is not present on Android. The best solution follows:
import android.os.Bundle;
import android.os.Handler;
public class Nome_da_Classe extends AppCompatActivity implements Runnable{
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
Handler handler = new Handler(); //contador de tempo
handler.postDelayed(this, 1500); //o exemplo 2000 = 2 segundos
}
@Override
public void run() {
//Esse métedo será execultado a cada período, ponha aqui a sua lógica
}
}
Note that I put some class codes so you can observe where each line of code is. It works, any problem or doubt is just ask!
import java.util.Timer;
import java.util.TimerTask;
public class Main extends AppCompatActivity {
public void Timer(){
Timer timer = new Timer();
Task task = new Task();
timer.schedule(task, 1000, 1000);
}
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Timer();
}
class Task extends TimerTask{
@Override
public void run() {
runOnUiThread(new Runnable() {
@Override
public void run() {
// Metodos
}
});
}
}
}
/ / let's go on the most important, the Timer class has a method called schedule, / / where this method receives the (TimerTask, long delay, long timesinmillis);
public void inicializaTimer() {
this.mCalendarDateFirst.setTimeInMillis(mTime);
this.mCalendarDateFirst.add(Calendar.HOUR, -1);
String data = this.mCalendarDateFirst.getTime().toString();
this.startaThread();
this.mTimer.schedule(this.mTimerTask, mCalendarDateFirst.getTime(), 1000);
}
public void startaThread() {
this.mTimerTask = new TimerTask() {
@Override
public void run() {
/ / today on android using the timetask run and the handle O POST method. if you want to know more query in the android documentation "processes and chaining".
mHandler.post(new Runnable() {
@Override
public void run() {
if (stop) {
mContext.stopService(new Intent(mContext, ServicoNotificacaoBackGround.class));
} else {
mCalendarAtual.setTimeInMillis(System.currentTimeMillis());
mCalendarHorario.setTimeInMillis(mTime);
Log.i("Data String", "Time " + mCalendarHorario.getTime().toString());
Log.i("Data String 2", "Time " + mCalendarAtual.getTime().toString());
if (mCalendarHorario.getTime().toString().equalsIgnoreCase(mCalendarAtual.getTime().toString())) {
stop = true;
}
Toast.makeText(ExampleService.this, "Foi ! ", Toast.LENGTH_SHORT).show();
Log.d("ExampleService", "Serviço Executando com Sucesso");
}
}
});
}
};
}
This is an example that could be the solution to the problem, i.e. running every 1 second.