| java.lang.Object | |
| ↳ | android.os.PowerManager.WakeLock |
A wake lock is a mechanism to indicate that your application needs to have the device stay on.
Any application using a WakeLock must request the android.permission.WAKE_LOCK
permission in an <uses-permission> element of the application's manifest.
Obtain a wake lock by calling newWakeLock(int, String).
Call acquire() to acquire the wake lock and force the device to stay
on at the level that was requested when the wake lock was created.
Call release() when you are done and don't need the lock anymore.
It is very important to do this as soon as possible to avoid running down the
device's battery excessively.
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Acquires the wake lock.
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Acquires the wake lock with a timeout.
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Returns true if the wake lock has been acquired but not yet released.
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Releases the wake lock.
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Sets whether this WakeLock is reference counted.
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Sets the work source associated with the wake lock.
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Returns a string containing a concise, human-readable description of this
object.
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Invoked when the garbage collector has detected that this instance is no longer reachable.
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Inherited Methods | |||||||||||
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From class
java.lang.Object
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Acquires the wake lock.
Ensures that the device is on at the level requested when the wake lock was created.
Acquires the wake lock with a timeout.
Ensures that the device is on at the level requested when the wake lock was created. The lock will be released after the given timeout expires.
| timeout | The timeout after which to release the wake lock, in milliseconds. |
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Returns true if the wake lock has been acquired but not yet released.
Releases the wake lock.
This method releases your claim to the CPU or screen being on. The screen may turn off shortly after you release the wake lock, or it may not if there are other wake locks still held.
Sets whether this WakeLock is reference counted.
Wake locks are reference counted by default. If a wake lock is
reference counted, then each call to acquire() must be
balanced by an equal number of calls to release(). If a wake
lock is not reference counted, then one call to release() is
sufficient to undo the effect of all previous calls to acquire().
| value | True to make the wake lock reference counted, false to make the wake lock non-reference counted. |
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Sets the work source associated with the wake lock.
The work source is used to determine on behalf of which application the wake lock is being held. This is useful in the case where a service is performing work on behalf of an application so that the cost of that work can be accounted to the application.
| ws | The work source, or null if none. |
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Returns a string containing a concise, human-readable description of this object. Subclasses are encouraged to override this method and provide an implementation that takes into account the object's type and data. The default implementation is equivalent to the following expression:
getClass().getName() + '@' + Integer.toHexString(hashCode())
See Writing a useful
toString method
if you intend implementing your own toString method.
Invoked when the garbage collector has detected that this instance is no longer reachable. The default implementation does nothing, but this method can be overridden to free resources.
Note that objects that override finalize are significantly more expensive than
objects that don't. Finalizers may be run a long time after the object is no longer
reachable, depending on memory pressure, so it's a bad idea to rely on them for cleanup.
Note also that finalizers are run on a single VM-wide finalizer thread,
so doing blocking work in a finalizer is a bad idea. A finalizer is usually only necessary
for a class that has a native peer and needs to call a native method to destroy that peer.
Even then, it's better to provide an explicit close method (and implement
Closeable), and insist that callers manually dispose of instances. This
works well for something like files, but less well for something like a BigInteger
where typical calling code would have to deal with lots of temporaries. Unfortunately,
code that creates lots of temporaries is the worst kind of code from the point of view of
the single finalizer thread.
If you must use finalizers, consider at least providing your own
ReferenceQueue and having your own thread process that queue.
Unlike constructors, finalizers are not automatically chained. You are responsible for
calling super.finalize() yourself.
Uncaught exceptions thrown by finalizers are ignored and do not terminate the finalizer thread. See Effective Java Item 7, "Avoid finalizers" for more.
| Throwable |
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