apple.foundation.enums

Class NSActivityOptions

java.lang.Object

apple.foundation.enums.NSActivityOptions

public final class NSActivityOptions
extends java.lang.Object

The system has heuristics to improve battery life, performance, and responsiveness of applications for the benefit of the user. This API can be used to give hints to the system that your application has special requirements. In response to creating one of these activities, the system will disable some or all of the heuristics so your application can finish quickly while still providing responsive behavior if the user needs it.

These activities can be used when your application is performing a long-running operation. If the activity can take different amounts of time (for example, calculating the next move in a chess game), it should use this API. This will ensure correct behavior when the amount of data or the capabilities of the user's computer varies. You should put your activity into one of two major categories:

User initiated: These are finite length activities that the user has explicitly started. Examples include exporting or downloading a user specified file.

Background: These are finite length activities that are part of the normal operation of your application but are not explicitly started by the user. Examples include autosaving, indexing, and automatic downloading of files.

In addition, if your application requires high priority IO, you can include the 'NSActivityLatencyCritical' flag (using a bitwise or). This should be reserved for activities like audio or video recording.

If your activity takes place synchronously inside an event callback on the main thread, you do not need to use this API.

Be aware that failing to end these activities for an extended period of time can have significant negative impacts to the performance of your user's computer, so be sure to use only the minimum amount of time required. User preferences may override your application’s request.

This API can also be used to control auto termination or sudden termination.

id activity = [NSProcessInfo.processInfo beginActivityWithOptions:NSActivityAutomaticTerminationDisabled reason:@"Good Reason"]; // work [NSProcessInfo.processInfo endActivity:activity];

is equivalent to:

[NSProcessInfo.processInfo disableAutomaticTermination:@"Good Reason"]; // work [NSProcessInfo.processInfo enableAutomaticTermination:@"Good Reason"]

Since this API returns an object, it may be easier to pair begins and ends. If the object is deallocated before the -endActivity: call, the activity will be automatically ended.

This API also provides a mechanism to disable system-wide idle sleep and display idle sleep. These can have a large impact on the user experience, so be sure not to forget to end activities that disable sleep (including NSActivityUserInitiated).

Field Summary

Fields

Modifier and Type	Field and Description
static long	AutomaticTerminationDisabled Prevents automatic termination.
static long	Background App has initiated some kind of work, but not as the direct result of user request.
static long	IdleDisplaySleepDisabled Used for activities that require the screen to stay powered on.
static long	IdleSystemSleepDisabled Used for activities that require the computer to not idle sleep.
static long	LatencyCritical Used for activities that require the highest amount of timer and I/O precision available.
static long	SuddenTerminationDisabled Prevents sudden termination.
static long	UserInitiated App is performing a user-requested action.
static long	UserInitiatedAllowingIdleSystemSleep App is performing a user-requested action.

Method Summary

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

IdleDisplaySleepDisabled

public static final long IdleDisplaySleepDisabled

Used for activities that require the screen to stay powered on.

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Constant Field Values

IdleSystemSleepDisabled

public static final long IdleSystemSleepDisabled

Used for activities that require the computer to not idle sleep. This is included in NSActivityUserInitiated.

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Constant Field Values

SuddenTerminationDisabled

public static final long SuddenTerminationDisabled

Prevents sudden termination. This is included in NSActivityUserInitiated.

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Constant Field Values

AutomaticTerminationDisabled

public static final long AutomaticTerminationDisabled

Prevents automatic termination. This is included in NSActivityUserInitiated.

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Constant Field Values

UserInitiated

public static final long UserInitiated

App is performing a user-requested action.

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Constant Field Values

UserInitiatedAllowingIdleSystemSleep

public static final long UserInitiatedAllowingIdleSystemSleep

App is performing a user-requested action.

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Constant Field Values

Background

public static final long Background

App has initiated some kind of work, but not as the direct result of user request.

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Constant Field Values

LatencyCritical

public static final long LatencyCritical

Used for activities that require the highest amount of timer and I/O precision available. Very few applications should need to use this constant.

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Constant Field Values