Perry answered for the WakeLock. What would be the problem in calling static methods of an abstract class? An abstract class prevents you from creating instances, and you are not trying to do so.
2014-12-03 17:38 GMT+01:00 Daniel Skinner <dan...@dasa.cc>: > just try it? In intellij, if I type `var wakeLock: WakeLock = null` and it > prompts to import `android.os.PowerManager.WakeLock` then the import > statement says "Cannot resolve symbol WakeLock`. If I clean and compile > from sbt console, I get "value WakeLock is not a member of object > android.os.PowerManager". > > Also, WakefulBroadcastReceiver is an abstract class, so no, I can't simply > call the static methods on it. > > On Wed, Dec 3, 2014 at 10:24 AM, Samuel Tardieu <s...@rfc1149.net> wrote: > >> >> >> 2014-12-03 17:09 GMT+01:00 Daniel Skinner <dan...@dasa.cc>: >> >>> I'm still learning a few things about scala but I'm wondering if anyone >>> has insight on accessing java statics from scala in relation to the Android >>> API. This rarely comes up but here's two examples. >>> >>> From https://developer.android.com/training/scheduling/wakelock.html >>> >>> The support library has a WakefulBroadcastReceiver that contains two >>> static methods. If i create a scala class that extends this, I can't access >>> the static methods for starting a wakeful service and finishing it. >>> >> >> What do you mean you “can’t access” them? You can imagine Java static >> methods as being roughly methods in a class companion object. You don’t >> inherit them, the way you wouldn’t inherit methods from a companion object >> as they don’t belong to the corresponding class, and they don’t operate on >> a particular instance. You need to access those methods by calling >> WakefulBroadcastReceiver.startWakefulService(…). In Java, being able to >> call them as if they were methods of your class is merely a convenience, >> they can’t access any of your non-static methods or fields anyway. >> >> >> . >> >>> >>> Likewise, >>> http://developer.android.com/reference/android/os/PowerManager.WakeLock.html >>> I can't declare a WakeLock type with something like `val wakeLock: WakeLock >>> = null`. >>> >> >> Again, what do you mean by “I can’t declare a WakeLock”? What happens if >> you do? I don’t see any reason you couldn’t declare one and assign it the >> null value (although an Option[WakeLock] would probably be best here). >> >> >> >> >>> >>> I have an intent service and worked around this with the following that >>> I access in onCreate and onDestroy (letting the type be inferred) >>> >>> lazy val (wakeLock, wifiLock) = { >>> val pm = >>> getSystemService(Context.POWER_SERVICE).asInstanceOf[PowerManager] >>> val wakeLock = pm.newWakeLock(PowerManager.PARTIAL_WAKE_LOCK, >>> "ClientWakeLock") >>> wakeLock.acquire() >>> val wm = >>> getSystemService(Context.WIFI_SERVICE).asInstanceOf[WifiManager] >>> val wifiLock = wm.createWifiLock(WifiManager.WIFI_MODE_FULL, >>> "ClientWifiLock") >>> wifiLock.acquire() >>> (wakeLock, wifiLock) >>> } >>> >>> but I'm wondering if there's some other way so that I can declare the >>> type. >>> >> >> What is wrong with the type (WakeLock, WifiLock)? >> >> Sam >> >> >> -- >> You received this message because you are subscribed to the Google Groups >> "scala-on-android" group. >> To unsubscribe from this group and stop receiving emails from it, send an >> email to scala-on-android+unsubscr...@googlegroups.com. >> For more options, visit https://groups.google.com/d/optout. >> > > -- > You received this message because you are subscribed to the Google Groups > "scala-on-android" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to scala-on-android+unsubscr...@googlegroups.com. > For more options, visit https://groups.google.com/d/optout. > -- You received this message because you are subscribed to the Google Groups "scala-on-android" group. To unsubscribe from this group and stop receiving emails from it, send an email to scala-on-android+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
