Restarting Java timer with a different time interval - java

I'm working on creating a timer in Java, and was wondering how I can use timer.cancel to then create a new timer which has a different interval.
My code looks something like this:
final Timer timer = new Timer();
timer.schedule(new TimerTask() {
#Override
public void run() {
handler.post(new Runnable() {
#Override
public void run() {
gameView.invalidate();
// timer.cancel(); - here, need to somehow restart timer with new interval
}
});
}
}, 0, TimerInterval.interval);
In another view, I'm modifying TimerInterval.interval, but this doesn't do anything/update the timer, because I need to somehow completely cancel the timer and create a new one, but I'm not sure how to do this.
Any help with this matter would be appreciated.

Related

Can I run timer at different intervals of time?

Actually i wanted to ask can i give value from database to a timer delay?
Timer timer = new Timer();
TimerTask timerTask = new TimerTask() {
#Override
public void run() {
runOnUiThread(new Runnable() {
#Override
public void run() {
// whatever
}
}
});
}
};
timer.schedule(timerTask,2000,**myDelay**); //here at my delay
Here at myDelay, can i give different values through database? Or it must be fixed?
If you are to change the time all the time with different values, I suggest you use
schedule(TimerTask task, long time)
Everytime you have a new time from DB, just create a new Timer() like so
time = getNewTimeFromDB();
createNewTask(time);
....
private void createNewTask(long time) {
Timer timer=new Timer();
TimerTask timerTask=new TimerTask() {
#Override
public void run() {
runOnUiThread(new Runnable() {
#Override
public void run() {
// whatever
}
});
}
};
timer.schedule(timerTask,time);
}
The good thing about this is you don't have to cancel the timer every single time because it is meant to run once.
May you should change your approach to the problem, create a function to return the time from the database FunctionToGetDelayFromDB();
Timer timer=new Timer();
long time = FunctionToGetTimeFromDB();
TimerTask timerTask=new TimerTask() {
#Override
public void run() {
runOnUiThread(new Runnable() {
#Override
public void run() {
// whatever
timer.schedule(timerTask, System.currentTimeMillis() + FunctionToGetDelayFromDB());
}
}
});
}
};
timer.schedule(timerTask, System.currentTimeMillis() + FunctionToGetDelayFromDB());
This should work for what you want to achieve...

How to cancel timerTask for AsyncTask in android

Hi I am working on TCP socket.
I can read data for every 1 sec. to achieve it I used TimerTask as shown in below code.
Handler handler = new Handler();
Timer timer = new Timer();
TimerTask doAsynchronousTask = new TimerTask() {
#Override
public void run() {
finalizer = new Runnable() {
public void run() {
try {
if (navBool) {
runOnUiThread(new Runnable() {
public void run() {
new RetriveStock().execute(); // AsyncTask.
}
});
}
} catch (Exception e) {
}
}
};
handler.post(finalizer);
}
};
timer.schedule(doAsynchronousTask, 0, 1000);
For canceling this timer I used code as
timer.cancel();
timer = null;
handler.removeCallbacks(finalizer);
But it is not cancelling the timer. I do not know why.
Instead of calling timer.cancel(), you should be canceling the task that is assigned to that timer (doAsynchronousTask in your case). Since multiple TimerTasks can be assigned to one timer, calling timer.cancel() will not interfere with a currently running task.
From the Timer JavaDoc:
public void cancel()
Terminates this timer, discarding any currently scheduled tasks. Does
not interfere with a currently executing task (if it exists). Once a
timer has been terminated, its execution thread terminates gracefully,
and no more tasks may be scheduled on it.

How to call asyncTasks periodically

I have two AsyncTasks doing network operations. I want to call them periodically (like after one min.). How do I do that? I dont think I can do it on the UI thread. Do i need to create a new thread? Is it possible to implemet this without AlarmManager/Service?
Basically I want to exectue these two statements periodically after one min.
new UploadAsyncTask().execute();
new DownloadAsyncTask().execute();
Thank you
Just use a timer.
final Handler handler = new Handler();
Timer timer = new Timer();
TimerTask task = new TimerTask() {
#Override
public void run() {
handler.post(new Runnable() {
public void run() {
new UploadAsyncTask().execute();
new DownloadAsyncTask().execute();
}
});
}
};
timer.schedule(task, 0, 1000); //it executes this every 1000ms

Using a counter inside a java.util.Timer in Android Activity causes app to crash

I'd like to accomplish something which I would think to be simple, but is turning out to be a hassle.
I have a loading screen with a picture, and I'd like for it to fade in and out as the application is loading. I decided to accomplish this by changing it's opacity frequently relative to the sine value of a counter. My code is as follows:
ImageView loadingRaven; //loading raven at the start of the app
Timer timer; //timer that we're gonna have to use
int elapsed = 0; //elapsed time so far
/*
* the following is in the onCreate() method after the ContentView has been set
*/
loadingRaven = (ImageView)findViewById(R.id.imageView1);
//fade the raven in and out
TimerTask task = new TimerTask()
{
public void run()
{
elapsed++;
//this line causes the app to fail
loadingRaven.setAlpha((float)(Math.sin(elapsed)+1)/2);
}
};
timer = new Timer();
timer.scheduleAtFixedRate(task, 0, 50);
What is the problem that's causing my program to fail? Am I correctly using Timer and TimerTask? Or is there perhaps a better way to update the opacity of the image frequently so it eases in and out smoothly?
Thanks
TimerTask runs on a different thread. So update ui on the main ui thread. Use runonuithread
TimerTask task = new TimerTask()
{
public void run()
{
elapsed++;
runOnUiThread(new Runnable() //run on ui thread
{
public void run()
{
loadingRaven.setAlpha((float)(Math.sin(elapsed)+1)/2)
}
});
}
};
TimerTask runs on a different thread. You can use Handler and postDelayed as suggested by
pskink

Timer and TimerTask Problem: "Timer.class not in android.jar" and "The Application Has Stopped Unexpectedly"?

So I'm trying to make a "live feed" essentially, and my code is shown below. Basically, I got "The Application Has Stopped Unexpectedly" error, so I debugged. When I debugged, it said "Timer.class not in android.jar". I know my refreshFeed() static method works perfectly fine (tested it without the timer), so it can't be that. Is there something I'm missing here? Any help is greatly appreciated!
Timer time = new Timer();
TimerTask refresh = new TimerTask(){
public void run(){
feedEntry.refreshFeed();
}
};
time.scheduleAtFixedRate(refresh, 0, 10000);
Both Timer and TimerTask present in java.util package.
What you need to is do is use handler.
Read about handler if you are new to android.
http://developer.android.com/reference/android/os/Handler.html
Handler handler = new Handler();
t = new Timer();
timeTask = new TimerTask() {
public void run() {
handler.post(new Runnable() {
public void run() {
feedEntry.refreshFeed();
}
});
}};
t.scheduleAtFixedRate(timeTask, 0, 1000);

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