Handling standby on iPad using Javascript -

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regarding ipad events, how determine if/when ipad changing awake state standby state?

what put mobile-safari web app in locked state whenever ipad becomes inactive/standby , ask pin when becomes awake again.

i agree there ought signal can hook on to know when application goes sleep , when wakes up, should able figure out when safari wakes indirectly.

when webview goes background, safari puts in sleep. pauses video, defers network request, stops updating ui , pauses setinterval/settimeout operations. js never aware (as far can tell) how these things happened, can tell has happened. simplest way use build regularly invoked method , check see if it's been unexpectedly long time since last update. if expect update every 10 seconds , it's been 5 minutes, can sure device has woken up. here's quick example thought up:

    var inttime = new date().gettime();     var gettime = function() {         var intnow = new date().gettime();         if (intnow - inttime > 1000) {             console.log("i woke up")         }         inttime = intnow;         settimeout(gettime,500);     };     gettime();

this detect when user has returned tab, has dismissed developer console or brought safari background. i've set interval @ half second; set @ need, though think low values have concurrency issues , burn battery down on device unnecessarily.


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