java.lang.Object | |
↳ | android.app.ActivityManager |
Interact with the overall activities running in the system.
Nested Classes | |||||||||||
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ActivityManager.MemoryInfo |
Information you can retrieve about the available memory through
getMemoryInfo(ActivityManager.MemoryInfo)
.
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ActivityManager.ProcessErrorStateInfo | Information you can retrieve about any processes that are in an error condition. | |||||||||
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ActivityManager.RecentTaskInfo | Information you can retrieve about tasks that the user has most recently started or visited. | |||||||||
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ActivityManager.RunningAppProcessInfo | Information you can retrieve about a running process. | |||||||||
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ActivityManager.RunningServiceInfo | Information you can retrieve about a particular Service that is currently running in the system. | |||||||||
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ActivityManager.RunningTaskInfo | Information you can retrieve about a particular task that is currently "running" in the system. |
Constants | |||||||||||
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String | META_HOME_ALTERNATE |
<meta-data>
name for a 'home' Activity that declares a package that is to be
uninstalled in lieu of the declaring one.
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int | MOVE_TASK_NO_USER_ACTION |
Flag for
moveTaskToFront(int, int)
: don't count this as a
user-instigated action, so the current activity will not receive a
hint that the user is leaving.
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int | MOVE_TASK_WITH_HOME |
Flag for
moveTaskToFront(int, int)
: also move the "home"
activity along with the task, so it is positioned immediately behind
the task.
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int | RECENT_IGNORE_UNAVAILABLE | Provides a list that does not contain any recent tasks that currently are not available to the user. | |||||||||
int | RECENT_WITH_EXCLUDED |
Flag for use with
getRecentTasks(int, int)
: return all tasks, even those
that have set their
FLAG_ACTIVITY_EXCLUDE_FROM_RECENTS
flag.
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Public Methods | |||||||||||
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Permits an application to erase its own data from disk.
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Perform a system dump of various state associated with the given application
package name.
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Get the device configuration attributes.
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Return the approximate per-application memory class of the current
device when an application is running with a large heap.
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Get the preferred density of icons for the launcher.
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Get the preferred launcher icon size.
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Return the approximate per-application memory class of the current
device.
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Return general information about the memory state of the system.
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Return global memory state information for the calling process.
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Return information about the memory usage of one or more processes.
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Returns a list of any processes that are currently in an error condition.
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Return a list of the tasks that the user has recently launched, with
the most recent being first and older ones after in order.
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Returns a list of application processes that are running on the device.
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Returns a PendingIntent you can start to show a control panel for the
given running service.
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Return a list of the services that are currently running.
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Return a list of the tasks that are currently running, with
the most recent being first and older ones after in order.
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Returns true if this is a low-RAM device.
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Returns "true" if device is running in a test harness.
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Returns "true" if the user interface is currently being messed with
by a monkey.
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Have the system immediately kill all background processes associated
with the given package.
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Ask that the task associated with a given task ID be moved to the
front of the stack, so it is now visible to the user.
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Equivalent to calling
moveTaskToFront(int, int, Bundle)
with a null options argument.
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This method was deprecated
in API level 8.
This is now just a wrapper for
killBackgroundProcesses(String)
; the previous behavior here
is no longer available to applications because it allows them to
break other applications by removing their alarms, stopping their
services, etc.
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[Expand]
Inherited Methods
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From class
java.lang.Object
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<meta-data>
name for a 'home' Activity that declares a package that is to be
uninstalled in lieu of the declaring one. The package named here must be
signed with the same certificate as the one declaring the
<meta-data>
.
Flag for
moveTaskToFront(int, int)
: don't count this as a
user-instigated action, so the current activity will not receive a
hint that the user is leaving.
Flag for
moveTaskToFront(int, int)
: also move the "home"
activity along with the task, so it is positioned immediately behind
the task.
Provides a list that does not contain any recent tasks that currently are not available to the user.
Flag for use with
getRecentTasks(int, int)
: return all tasks, even those
that have set their
FLAG_ACTIVITY_EXCLUDE_FROM_RECENTS
flag.
Permits an application to erase its own data from disk. This is equivalent to the user choosing to clear the app's data from within the device settings UI. It erases all dynamic data associated with the app -- its private data and data in its private area on external storage -- but does not remove the installed application itself, nor any OBB files.
true
if the application successfully requested that the application's
data be erased;
false
otherwise.
Perform a system dump of various state associated with the given application
package name. This call blocks while the dump is being performed, so should
not be done on a UI thread. The data will be written to the given file
descriptor as text. An application must hold the
DUMP
permission to make this call.
fd | The file descriptor that the dump should be written to. The file descriptor is not closed by this function; the caller continues to own it. |
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packageName | The name of the package that is to be dumped. |
Get the device configuration attributes.
Return the approximate per-application memory class of the current
device when an application is running with a large heap. This is the
space available for memory-intensive applications; most applications
should not need this amount of memory, and should instead stay with the
getMemoryClass()
limit. The returned value is in megabytes.
This may be the same size as
getMemoryClass()
on memory
constrained devices, or it may be significantly larger on devices with
a large amount of available RAM.
The is the size of the application's Dalvik heap if it has
specified
android:largeHeap="true"
in its manifest.
Get the preferred density of icons for the launcher. This is used when custom drawables are created (e.g., for shortcuts).
Get the preferred launcher icon size. This is used when custom drawables are created (e.g., for shortcuts).
Return the approximate per-application memory class of the current device. This gives you an idea of how hard a memory limit you should impose on your application to let the overall system work best. The returned value is in megabytes; the baseline Android memory class is 16 (which happens to be the Java heap limit of those devices); some device with more memory may return 24 or even higher numbers.
Return general information about the memory state of the system. This
can be used to help decide how to manage your own memory, though note
that polling is not recommended and
ComponentCallbacks2.onTrimMemory(int)
is the preferred way to do this.
Also see
getMyMemoryState(ActivityManager.RunningAppProcessInfo)
for how to retrieve the current trim
level of your process as needed, which gives a better hint for how to
manage its memory.
Return global memory state information for the calling process. This
does not fill in all fields of the
ActivityManager.RunningAppProcessInfo
. The
only fields that will be filled in are
pid
,
uid
,
lastTrimLevel
,
importance
,
lru
, and
importanceReasonCode
.
Return information about the memory usage of one or more processes.
Note: this method is only intended for debugging or building a user-facing process management UI.
pids | The pids of the processes whose memory usage is to be retrieved. |
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Returns a list of any processes that are currently in an error condition. The result will be null if all processes are running properly at this time.
Return a list of the tasks that the user has recently launched, with the most recent being first and older ones after in order.
Note: this method is only intended for debugging and presenting task management user interfaces . This should never be used for core logic in an application, such as deciding between different behaviors based on the information found here. Such uses are not supported, and will likely break in the future. For example, if multiple applications can be actively running at the same time, assumptions made about the meaning of the data here for purposes of control flow will be incorrect.
maxNum | The maximum number of entries to return in the list. The actual number returned may be smaller, depending on how many tasks the user has started and the maximum number the system can remember. |
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flags |
Information about what to return. May be any combination
of
RECENT_WITH_EXCLUDED
and
RECENT_IGNORE_UNAVAILABLE
.
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SecurityException |
Throws SecurityException if the caller does
not hold the
GET_TASKS
permission.
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Returns a list of application processes that are running on the device.
Note: this method is only intended for debugging or building a user-facing process management UI.
Returns a PendingIntent you can start to show a control panel for the given running service. If the service does not have a control panel, null is returned.
SecurityException |
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Return a list of the services that are currently running.
Note: this method is only intended for debugging or implementing service management type user interfaces.
maxNum | The maximum number of entries to return in the list. The actual number returned may be smaller, depending on how many services are running. |
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SecurityException |
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Return a list of the tasks that are currently running, with the most recent being first and older ones after in order. Note that "running" does not mean any of the task's code is currently loaded or activity -- the task may have been frozen by the system, so that it can be restarted in its previous state when next brought to the foreground.
Note: this method is only intended for debugging and presenting task management user interfaces . This should never be used for core logic in an application, such as deciding between different behaviors based on the information found here. Such uses are not supported, and will likely break in the future. For example, if multiple applications can be actively running at the same time, assumptions made about the meaning of the data here for purposes of control flow will be incorrect.
maxNum | The maximum number of entries to return in the list. The actual number returned may be smaller, depending on how many tasks the user has started. |
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SecurityException |
Throws SecurityException if the caller does
not hold the
GET_TASKS
permission.
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Returns true if this is a low-RAM device. Exactly whether a device is low-RAM is ultimately up to the device configuration, but currently it generally means something in the class of a 512MB device with about a 800x480 or less screen. This is mostly intended to be used by apps to determine whether they should turn off certain features that require more RAM.
Returns "true" if device is running in a test harness.
Returns "true" if the user interface is currently being messed with by a monkey.
Have the system immediately kill all background processes associated with the given package. This is the same as the kernel killing those processes to reclaim memory; the system will take care of restarting these processes in the future as needed.
You must hold the permission
KILL_BACKGROUND_PROCESSES
to be able to
call this method.
packageName | The name of the package whose processes are to be killed. |
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Ask that the task associated with a given task ID be moved to the
front of the stack, so it is now visible to the user. Requires that
the caller hold permission
REORDER_TASKS
or a SecurityException will be thrown.
taskId |
The identifier of the task to be moved, as found in
ActivityManager.RunningTaskInfo
or
ActivityManager.RecentTaskInfo
.
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flags |
Additional operational flags, 0 or more of
MOVE_TASK_WITH_HOME
,
MOVE_TASK_NO_USER_ACTION
.
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options |
Additional options for the operation, either null or
as per
Context.startActivity(Intent, Bundle)
.
|
Equivalent to calling
moveTaskToFront(int, int, Bundle)
with a null options argument.
taskId |
The identifier of the task to be moved, as found in
ActivityManager.RunningTaskInfo
or
ActivityManager.RecentTaskInfo
.
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flags |
Additional operational flags, 0 or more of
MOVE_TASK_WITH_HOME
,
MOVE_TASK_NO_USER_ACTION
.
|
This method was deprecated
in API level 8.
This is now just a wrapper for
killBackgroundProcesses(String)
; the previous behavior here
is no longer available to applications because it allows them to
break other applications by removing their alarms, stopping their
services, etc.