So I need to have a timer to count down from 60 seconds. I am new to Xamarin and have no idea what it accepts. It will be used in Android.
Any suggestions on how to start?
Can you use System.Timers.Timer?
So I need to have a timer to count down from 60 seconds. I am new to Xamarin and have no idea what it accepts. It will be used in Android.
Any suggestions on how to start?
Can you use System.Timers.Timer?
You can use the System.Threading.Timer class, which is documented in the Xamarin docs: https://developer.xamarin.com/api/type/System.Threading.Timer/
Alternatively, for Xamarin.Forms, you have access to a cross-platform Timer via the Device class:
Device.StartTimer(TimeSpan.FromSeconds(1), () =>
{
// called every 1 second
// do stuff here
return true; // return true to repeat counting, false to stop timer
});
If you just need Android you can use
System.Threading.Timer
In shared code with Xamarin Forms you can use
Device.StartTimer(...)
Or you can implement one yourselfe with advanced features like:
public sealed class Timer : CancellationTokenSource {
private readonly Action _callback;
private int _millisecondsDueTime;
private readonly int _millisecondsPeriod;
public Timer(Action callback, int millisecondsDueTime) {
_callback = callback;
_millisecondsDueTime = millisecondsDueTime;
_millisecondsPeriod = -1;
Start();
}
public Timer(Action callback, int millisecondsDueTime, int millisecondsPeriod) {
_callback = callback;
_millisecondsDueTime = millisecondsDueTime;
_millisecondsPeriod = millisecondsPeriod;
Start();
}
private void Start() {
Task.Run(() => {
if (_millisecondsDueTime <= 0) {
_millisecondsDueTime = 1;
}
Task.Delay(_millisecondsDueTime, Token).Wait();
while (!IsCancellationRequested) {
//TODO handle Errors - Actually the Callback should handle the Error but if not we could do it for the callback here
_callback();
if(_millisecondsPeriod <= 0) break;
if (_millisecondsPeriod > 0 && !IsCancellationRequested) {
Task.Delay(_millisecondsPeriod, Token).Wait();
}
}
});
}
public void Stop() {
Cancel();
}
protected override void Dispose(bool disposing) {
if (disposing) {
Cancel();
}
base.Dispose(disposing);
}
}
Yes, you can use System.Timers.Timer.
In Android we can use java.util.Timer like this:
private int i;
final Timer timer=new Timer();
TimerTask task=new TimerTask() {
@Override
public void run() {
if (i < 60) {
i++;
} else {
timer.cancel();
}
Log.e("time=",i+"");
}
};
timer.schedule(task, 0,1000);
In Xamarin.Android we can also use java.util.Timer like this:
[Activity(Label = "Tim", MainLauncher = true)]
public class MainActivity : Activity
{
protected override void OnCreate(Bundle savedInstanceState)
{
base.OnCreate(savedInstanceState);
// Set our view from the "main" layout resource
SetContentView(Resource.Layout.Main);
Timer timer = new Timer();
timer.Schedule(new MyTask(timer),0,1000);
}
}
class MyTask : TimerTask
{
Timer mTimer;
public MyTask(Timer timer) {
this.mTimer = timer;
}
int i;
public override void Run()
{
if (i < 60)
{
i++;
}
else {
mTimer.Cancel();
}
Android.Util.Log.Error("time",i+"");
}
}
You can always use
Task.Factory.StartNewTaskContinuously(YourMethod, new CancellationToken(), TimeSpan.FromMinutes(10));
Be sure to add the following class to your project
static class Extensions
{
/// <summary>
/// Start a new task that will run continuously for a given amount of time.
/// </summary>
/// <param name="taskFactory">Provides access to factory methods for creating System.Threading.Tasks.Task and System.Threading.Tasks.Task`1 instances.</param>
/// <param name="action">The action delegate to execute asynchronously.</param>
/// <param name="cancellationToken">The System.Threading.Tasks.TaskFactory.CancellationToken that will be assigned to the new task.</param>
/// <param name="timeSpan">The interval between invocations of the callback.</param>
/// <returns>The started System.Threading.Tasks.Task.</returns>
public static Task StartNewTaskContinuously(this TaskFactory taskFactory, Action action, CancellationToken cancellationToken, TimeSpan timeSpan
, string taskName = "")
{
return taskFactory.StartNew(async () =>
{
if (!string.IsNullOrEmpty(taskName))
{
Debug.WriteLine("Started task " + taskName);
}
while (!cancellationToken.IsCancellationRequested)
{
action();
try
{
await Task.Delay(timeSpan, cancellationToken);
}
catch (Exception e)
{
break;
}
}
if (!string.IsNullOrEmpty(taskName))
{
Debug.WriteLine("Finished task " + taskName);
}
});
}
}