I would like to start a task at a specific time. For that I use runnable and postDelayed method as follows:
private Runnable mLaunchTask = new Runnable() {
public void run() {
try {
MY TASK
} catch (IllegalStateException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
}
};
In my code I use mLunchTask as follows:
mHandler = new Handler();
mHandler.postDelayed(mLaunchTask, myDelay*1000);
and myDelay is computed as follows:
s = DateFormat.format("hh:mm:ss aaa", d.getTime());
cTime = s.toString(); // current Time
ch = Integer.parseInt(cTime.substring(0,2)); // current hour
cm = Integer.parseInt(cTime.substring(3,5)); // current minute
cs = Integer.parseInt(cTime.substring(6,8)); // current second
if (cTime.substring(9,11).equalsIgnoreCase("pm") && (ch<12) ) ch = ch+12;
myDelay=(desiredHour-ch)*3600+(desiredMinute-cm)*60 - cs;
if (myDelay<0) myDelay = 0;
and desiredHour and desiredMinute are set by user. The expectation is that MY TASK starts at desiredHour and desiredMinute and 0 seconds.
However "MY TASK starts with a few seconds delay, which looks like is random.
Based on the above code, is there any reason that it does not start at the exact desired time?
Thanks
First of all, your delay calculation is correct, but the "pm" detection doesn't work with other languages. It is much better to use the calendar to get the delay:
Calendar calendar = Calendar.getInstance();
long currentTimestamp = calendar.getTimeInMillis();
calendar.set(Calendar.HOUR_OF_DAY, desiredHour);
calendar.set(Calendar.MINUTE, desiredMinute);
calendar.set(Calendar.SECOND, 0);
long diffTimestamp = calendar.getTimeInMillis() - currentTimestamp;
long myDelay = (diffTimestamp < 0 ? 0 : diffTimestamp);
Now you have the delay in milli secs and can start the handler:
new Handler().postDelayed(mLaunchTask, myDelay);
In my test the following runnable logs at the desired time with no delay.
private Runnable mLaunchTask = new Runnable() {
public void run() {
Calendar calendar = Calendar.getInstance();
Log.d("test", "started at "
+ calendar.get(Calendar.HOUR_OF_DAY) + " "
+ calendar.get(Calendar.MINUTE) + " "
+ calendar.get(Calendar.SECOND)
);
}
};
Maybe your started task needs some seconds to be loaded?
Could the AlarmManager be an alternative?
Based on my experience and reading of the documentation, postDelayed is based on uptime, not real time. If the phone goes into deep sleep, it can cause real time to pass without uptime incrementing. That means your task will start later than desired.
The Handler really seems to be designed for updating the GUI in an active activity, not scheduling tasks far in the future. As scessor said, AlarmManager is probably your best bet.
The Naliba's answer is not completely correct.
Based on documentation that can be seen here
it can be seen that this class is specifically used for running tasks in the future.
"There are two main uses for a Handler: (1) to schedule messages and runnables to be executed as some point in the future; and (2) to enqueue an action to be performed on a different thread than your own. "
There is no reference about the behavior of the application when the system enters in sleep mode and this issue should be tested before posting additional information.
Related
Need to create stopwatch in android, for now I'v got somethink like this, simple function to start counting and display time, but i dont know what am I doing wrong with postdelayed:
fun runTimer() {
val timeView = findViewById<TextView>(R.id.time_view)
val handler = Handler()
handler.post(Runnable {
var hours = seconds / 3600
var minutes = (seconds % 3600) / 60
var secs = seconds % 60
var time = String.format("%d:%02d:%02d", hours, minutes, secs)
timeView.setText(time)
if (running) {
seconds++
}
handler.postDelayed(this, 1000)
})
}
what exactly should i put instead of this? (need to be runnable type)
I believe in your use case the most suitable solution would be to use a Chronometer - you can read more about it here. Also if you want to watch a video tutorial you can check this video. Hope this helps. Additionally if you want to have the functionality to be able to set a specific time frame and countdown using a CountDownTimer is a good option - documentation
I use handler as Timer like this :
class TimerClass {
fun startTimer( handler : Handler ,
stuffToDo : () -> Unit ,
stopTimeInSeconds : Int ,
timePassed : Int ,
interval : Long){
handler.postDelayed( {
stuffToDo.invoke()
if (timePassed < stopTimeInSeconds){
startTimer(handler ,
stuffToDo ,
stopTimeInSeconds ,
timePassed + 1 ,
interval)
}
} , interval)
}}
then to use it :
val time = TestClass()
time.startTimer(handler = Handler() ,
stuffToDo = { textView.text = "some new text" } ,
stopTimeInSeconds = 5 ,
timePassed = 0 ,
interval = 1000)
So you define a method in the class , and provide all dependencies(objects) and injecting to it, you are creating the operation you want to do as a lambda function. then call the handler delayed method and in the handler if the criteria (if statement) is true you will call the method itself recursively with an increment (timePassed+1).
Now you have a working timer.
I'm trying to use UsageStatsManager to get the foreground app on a Nexus 5 with Marshmallow. I remember it used to work, but for some reason I'm getting null strings for package/class names now.
Here's my implementation
public String[] getForegroundPackageNameClassNameByUsageStats() {
String packageNameByUsageStats = null;
String classByUsageStats = null;
if(Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) {
UsageStatsManager mUsageStatsManager = (UsageStatsManager)getSystemService("usagestats");
final long INTERVAL = 1000;
final long end = System.currentTimeMillis();
final long begin = end - INTERVAL;
final UsageEvents usageEvents = mUsageStatsManager.queryEvents(begin, end);
while (usageEvents.hasNextEvent()) {
UsageEvents.Event event = new UsageEvents.Event();
usageEvents.getNextEvent(event);
if (event.getEventType() == UsageEvents.Event.MOVE_TO_FOREGROUND) {
packageNameByUsageStats = event.getPackageName();
classByUsageStats = event.getClassName();
Log.d(TAG, "packageNameByUsageStats is" + packageNameByUsageStats + ", classByUsageStats is " + classByUsageStats);
}
}
}
return new String[]{packageNameByUsageStats,classByUsageStats};
}
For some reason, it doesn't go into the while loop, i.e. usageEvents.hasNextEvent() is false. Because of this, it returns null package/class names.
Any idea what I'm doing wrong?
Thanks.
OK, so I found that once I set the interval to 10000 instead of 1000, it works. Apparently a 1s interval is too small.
I am using this myself. I think the usage stats will only be updated when an app comes to foreground. So if the foreground app got to the foreground (and stayed) before your 'begin' timestamp then you will not get it. :(
On the other hand when you use a long time ago you will get a giant list where you only need the highest time to determine the foreground app.
So what I do is I create 3 different times: 1min ago, 1 hour ago and 12 hours ago.
When I get an empty list on 1min I repeat request with 1h and so on. That way I get foreground most of the time. But I never get it to work ALL of the time.
I really miss the old way of just asking the package manager which app is foreground (prior to android 5), the new way is a bit messy.
I am writing a cross-platform application in Cocos2d-x. I need to get the time to create a countdown clock to a certain time of day. Since it is in C++, I can use time(...), mktime(...), and difftime(...) if I need to as a direct approach.
Is there a preferred method in Cocos2d-x for doing this in a cross-platform way (i.e. something built directly into the framework)? I want the app to work the same on iPhones, iPads, and Android.
try this:
time_t rawtime;
struct tm * timeinfo;
time (&rawtime);
timeinfo = localtime (&rawtime);
CCLog("year------->%04d",timeinfo->tm_year+1900);
CCLog("month------->%02d",timeinfo->tm_mon+1);
CCLog("day------->%02d",timeinfo->tm_mday);
CCLog("hour------->%02d",timeinfo->tm_hour);
CCLog("minutes------->%02d",timeinfo->tm_min);
CCLog("seconds------->%02d",timeinfo->tm_sec);
Try this code
static inline long millisecondNow()
{
struct cc_timeval now;
CCTime::gettimeofdayCocos2d(&now, NULL);
return (now.tv_sec * 1000 + now.tv_usec / 1000);
}
I used this function to get current time in millisecond. I am new in cocos2d-x so hope this can be helpful.
You should try this lib, I just tested and it works fine.
https://github.com/Ghost233/CCDate
If you receive some wrong values, set timezoneOffset = 0;
Note: 0 <= month <= 11
You can sheduleUpdate in clock class.
The update call with a float argument which is a delta time in seconds after last calls, this method is called every frame and cocos2d-x get time through from the system and count the delta.
I thought this code would do the trick:
static inline long millisecondNow()
{
struct cc_timeval now;
CCTime::gettimeofdayCocos2d(&now, NULL);
return (now.tv_sec * 1000 + now.tv_usec / 1000);
}
HOWEVER, only gives a part of what I need. In general, I need a real "date and time" object (or structure), not just the time of day in milliseconds.
The best solution, for now, seems to be using the "classic" localtime, mktime, difftime trifecta in C++. I have a few examples below of some basic operations...I may cook up a general class to do these kinds of operations, but for now, these are a good start and show how to get moving:
double Utilities::SecondsTill(int hour, int minute)
{
time_t now;
struct tm target;
double seconds;
time(&now);
target = *localtime(&now);
target.tm_hour = hour;
target.tm_min = minute;
target.tm_sec = 0;
seconds = difftime(mktime(&target),now);
return seconds;
}
DAYS_OF_WEEK_T Utilities::GetDayOfWeek()
{
struct tm tinfo;
time_t rawtime;
time (&rawtime);
tinfo = *localtime(&rawtime);
return (DAYS_OF_WEEK_T)tinfo.tm_wday;
}
i runing this code on android after load a cursor with the query i pass to the adapter, but my date is in long in milliseconds format so i need to format properly before load the adapter!
problem is this code is taking 14 seconds to pass a 50 items load, the problem get worst if i call it inside the adapter getView cause get slow when i scrool, if i take this function out the program runs smoothly
this is call inside my listfragment
private String dateFormatPatternEdited(long timeMS) {
android.text.format.DateFormat df = new android.text.format.DateFormat();
final Calendar eDate = Calendar.getInstance();
Calendar sDate = Calendar.getInstance();
sDate.setTimeInMillis(timeMS);
long daysBetween = 0;
while (sDate.before(eDate)) {
sDate.add(Calendar.DAY_OF_MONTH, 1);
daysBetween++;
}
String mDateFormatPattern = FuelTrackerApplication.dateFormat.format(timeMS);
if (daysBetween < 2){
mDateFormatPattern = FuelTrackerApplication.timeFormat.format(timeMS);
} else if(daysBetween < 365){
mDateFormatPattern = df.format(FuelTrackerApplication.dateFormatPattern,timeMS).toString();
}
return mDateFormatPattern;
}
and this is were i initialize the date formats i gonna use its called inside onCreate in FuelTrackerApplication i dont think theres nothing wrong with this
public void initializeDateFormat() {
android.text.format.DateFormat df = new android.text.format.DateFormat();
dateFormatPattern = "MMM dd";
if (android.os.Build.VERSION.SDK_INT >= 18){
dateFormatPattern = df.getBestDateTimePattern(Locale.getDefault(), dateFormatPattern);
}
dateFormat = df.getMediumDateFormat(getApplicationContext());
timeFormat = df.getTimeFormat(getApplicationContext());
dateFormat2 = df.getLongDateFormat(getApplicationContext());
}
Ok just a few things. Depending on how long ago your dates are going back. You are only interested if the days between go more then 365. So if your dates are going back for years, you're doing extra work.
while (sDate.before(eDate) && daysBetween <= 365) {
sDate.add(Calendar.DAY_OF_MONTH, 1);
daysBetween++;
}
Will let it break, it means if you have 20 entries going back 5 years, you don't do so much work.
It might be worth while to possibly just check the milliseconds difference. I'm not sure if this is precise enough, but it should work. It means you don't need to loop everything E.g
long millisecondsToday = getMilliseconds;
long timeMs = // you already have this
long millisecondsDifference = millisecondsToday - timeMs;
if (millisecondsDifference < MILLISECONDS_TWO_DAYS) // set a final variable out of this method
// etc
If might also be worth while initialising some of your variables once outside of the method. Like your df, that is being created 50 times, and then just having something set on it. Same with your eDate.
i got this incredible faster and practicaly remove the hole function
instead goes like this
lDateBetween = NOW - timeMS;
if (lDateBetween < DAY)
return FuelTrackerApplication.timeFormat.format(timeMS);
else if (lDateBetween < YEAR)
return df.format(FuelTrackerApplication.dateFormatPattern,timeMS).toString();
else return FuelTrackerApplication.dateFormat.format(timeMS);
all calculation is made using milliseconds i also put 2 final NOW and YEAR, also df and lDateBetween
i think is the fastest i can get!
I have some things in my Android application that need to update once per day.
It's pretty simple I think, but I have no idea in what format I need to format the date and time (if time is needed) and how to check if an update has been done today (where today is between 00:01am and 23:59pm in the user's local time). The update should not be done if it was already done for today.
Here's what I DO know how to do:
Save the last update date in SharedPreferences (but how do I get a
string of it, I do not know)
Get things from SharedPreferences (but I
don't know how to compare dates in string format)
It is irrelevant what format you choose. It is just matter of recalculations.
I'd suggest using milliseconds since epoch, as all system calls use it, so it would be easier for you to use the same.
As 1000 millis is 1 second it's easy to figure out that 1000*60*60*24 equals to one day (24hrs). So, if storedMillis is bigger than NOW - 1000*60*60*24, (and NOW is i.e. System.currentTimeMillis()), then it is too early to do the check. If storedMillis is smaller, then save your NOW timestamp and do the check:
long now = System.currentTimeMillis();
long diffMillis = now - lastCheckedMillis;
if( diffMillis >= (3600000 * 24) ) {
// store now (i.e. in shared prefs)
// do the check
} else {
// too early
}
EDIT
I am interested in doing it when the app is first opened for the
current day, even if the last update was done 10 minutes ago.
It's just the matter how to get the proper millis to compare against. Replace long now = System.currentTimeMillis(); from above code with following code block:
Calendar cal = Calendar.getInstance();
cal.clear(Calendar.HOUR);
cal.clear(Calendar.HOUR_OF_DAY);
cal.clear(Calendar.MINUTE);
cal.clear(Calendar.SECOND);
cal.clear(Calendar.MILLISECOND);
long now = cal.getTimeInMillis();
which shall do the trick.
If you store your date in format 20121122 (YYYYmmdd) then you can compare is like 20121122 > 20121123. But it must be stored as int or cast to int when comparing.
Store the timestamp (System.currentTimeMillis() ) of the Last execution and compair it with the currient one. If the difference is more than 24 hours... You know it or?
Set up an Alarm with AlarmManager that executes every 24 hours, then do stuff
Check this question: Alarm Manager Example
It's a more complicated approach than the rest, but makes sure things are done, while with the other options the app must be executed in order to check if it has to update whatever.
Here is the method
public boolean runOnceADay() {
SharedPreferences shp= c.getSharedPreferences(Constants.GENERAL_SHP, MODE_PRIVATE);
SharedPreferences.Editor editor= shp.edit();
long lastCheckedMillis = shp.getLong(Constants.ONCE_A_DAY, 0); // "KEY" you may change yhe value
long now = System.currentTimeMillis();
long diffMillis = now - lastCheckedMillis;
if (diffMillis >= (3600000 * 24)) { // set up your time circulation
editor.putLong(Constants.ONCE_A_DAY, now);
editor.commit();
Util.showMessage(c, "Once a Day Test");
return false;
} else {
Util.showMessage(c, "Too Early");
return true;
}
}