ActivityManager
public
class
ActivityManager
extends Object
java.lang.Object | |
↳ | android.app.ActivityManager |
This class gives information about, and interacts with, activities, services, and the containing process.
A number of the methods in this class are for debugging or informational purposes and they should not be used to affect any runtime behavior of your app. These methods are called out as such in the method level documentation.
Most application developers should not have the need to
use this class, most of whose methods are for specialized
use cases. However, a few methods are more broadly applicable.
For instance, isLowRamDevice()
enables your app to detect whether it is running on a low-memory device,
and behave accordingly.
clearApplicationUserData()
is for apps with reset-data functionality.
In some special use cases, where an app interacts with
its Task stack, the app may use the
ActivityManager.AppTask
and
ActivityManager.RecentTaskInfo
inner
classes. However, in general, the methods in this class should
be used for testing and debugging purposes only.
Summary
Nested classes | |
---|---|
class |
ActivityManager.AppTask
The AppTask allows you to manage your own application's tasks. |
class |
ActivityManager.MemoryInfo
Information you can retrieve about the available memory through
|
class |
ActivityManager.ProcessErrorStateInfo
Information you can retrieve about any processes that are in an error condition. |
class |
ActivityManager.RecentTaskInfo
Information you can retrieve about tasks that the user has most recently started or visited. |
class |
ActivityManager.RunningAppProcessInfo
Information you can retrieve about a running process. |
class |
ActivityManager.RunningServiceInfo
Information you can retrieve about a particular Service that is currently running in the system. |
class |
ActivityManager.RunningTaskInfo
Information you can retrieve about a particular task that is currently "running" in the system. |
class |
ActivityManager.TaskDescription
Information you can set and retrieve about the current activity within the recent task list. |
Constants | |
---|---|
String |
ACTION_REPORT_HEAP_LIMIT
Action an app can implement to handle reports from |
int |
LOCK_TASK_MODE_LOCKED
Full lock task mode is active. |
int |
LOCK_TASK_MODE_NONE
Lock task mode is not active. |
int |
LOCK_TASK_MODE_PINNED
App pinning mode is active. |
String |
META_HOME_ALTERNATE
|
int |
MOVE_TASK_NO_USER_ACTION
Flag for |
int |
MOVE_TASK_WITH_HOME
Flag for |
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 |
Public methods | |
---|---|
int
|
addAppTask(Activity activity, Intent intent, ActivityManager.TaskDescription description, Bitmap thumbnail)
Add a new |
void
|
addApplicationStartInfoCompletionListener(Executor executor, Consumer<ApplicationStartInfo> listener)
Adds a callback that is notified when the |
void
|
addStartInfoTimestamp(int key, long timestampNs)
Adds an optional developer supplied timestamp to the calling apps most recent
|
void
|
appNotResponding(String reason)
Method for the app to tell system that it's wedged and would like to trigger an ANR. |
boolean
|
clearApplicationUserData()
Permits an application to erase its own data from disk. |
void
|
clearWatchHeapLimit()
Clear a heap watch limit previously set by |
void
|
dumpPackageState(FileDescriptor fd, String packageName)
Perform a system dump of various state associated with the given application package name. |
Size
|
getAppTaskThumbnailSize()
Return the current design dimensions for |
List<ActivityManager.AppTask>
|
getAppTasks()
Get the list of tasks associated with the calling application. |
ConfigurationInfo
|
getDeviceConfigurationInfo()
Get the device configuration attributes. |
List<ApplicationExitInfo>
|
getHistoricalProcessExitReasons(String packageName, int pid, int maxNum)
Return a list of |
List<ApplicationStartInfo>
|
getHistoricalProcessStartReasons(int maxNum)
Return a list of |
int
|
getLargeMemoryClass()
Return the approximate per-application memory class of the current device when an application is running with a large heap. |
int
|
getLauncherLargeIconDensity()
Get the preferred density of icons for the launcher. |
int
|
getLauncherLargeIconSize()
Get the preferred launcher icon size. |
int
|
getLockTaskModeState()
Return the current state of task locking. |
int
|
getMemoryClass()
Return the approximate per-application memory class of the current device. |
void
|
getMemoryInfo(ActivityManager.MemoryInfo outInfo)
Return general information about the memory state of the system. |
static
void
|
getMyMemoryState(ActivityManager.RunningAppProcessInfo outState)
Return global memory state information for the calling process. |
MemoryInfo[]
|
getProcessMemoryInfo(int[] pids)
Return information about the memory usage of one or more processes. |
List<ActivityManager.ProcessErrorStateInfo>
|
getProcessesInErrorState()
Returns a list of any processes that are currently in an error condition. |
List<ActivityManager.RecentTaskInfo>
|
getRecentTasks(int maxNum, int flags)
This method was deprecated
in API level 21.
As of |
List<ActivityManager.RunningAppProcessInfo>
|
getRunningAppProcesses()
Returns a list of application processes that are running on the device. |
PendingIntent
|
getRunningServiceControlPanel(ComponentName service)
Returns a PendingIntent you can start to show a control panel for the given running service. |
List<ActivityManager.RunningServiceInfo>
|
getRunningServices(int maxNum)
This method was deprecated
in API level 26.
As of |
List<ActivityManager.RunningTaskInfo>
|
getRunningTasks(int maxNum)
This method was deprecated
in API level 21.
As of |
boolean
|
isActivityStartAllowedOnDisplay(Context context, int displayId, Intent intent)
Check if the context is allowed to start an activity on specified display. |
boolean
|
isBackgroundRestricted()
Query whether the user has enabled background restrictions for this app. |
boolean
|
isInLockTaskMode()
This method was deprecated
in API level 23.
Use |
static
boolean
|
isLowMemoryKillReportSupported()
|
boolean
|
isLowRamDevice()
Returns true if this is a low-RAM device. |
static
boolean
|
isRunningInTestHarness()
This method was deprecated
in API level 29.
this method is false for all user builds. Users looking to check if their device
is running in a device farm should see |
static
boolean
|
isRunningInUserTestHarness()
Returns "true" if the device is running in Test Harness Mode. |
static
boolean
|
isUserAMonkey()
Returns "true" if the user interface is currently being messed with by a monkey. |
void
|
killBackgroundProcesses(String packageName)
Have the system immediately kill all background processes associated with the given package. |
void
|
moveTaskToFront(int taskId, int flags, Bundle options)
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. |
void
|
moveTaskToFront(int taskId, int flags)
Equivalent to calling |
void
|
removeApplicationStartInfoCompletionListener(Consumer<ApplicationStartInfo> listener)
Removes the provided callback set by |
void
|
restartPackage(String packageName)
This method was deprecated
in API level 15.
This is now just a wrapper for
|
void
|
setProcessStateSummary(byte[] state)
Set custom state data for this process. |
static
void
|
setVrThread(int tid)
Enable more aggressive scheduling for latency-sensitive low-runtime VR threads. |
void
|
setWatchHeapLimit(long pssSize)
Request that the system start watching for the calling process to exceed a pss size as given here. |
Inherited methods | |
---|---|
Constants
ACTION_REPORT_HEAP_LIMIT
public static final String ACTION_REPORT_HEAP_LIMIT
Action an app can implement to handle reports from setWatchHeapLimit(long)
.
If your package has an activity handling this action, it will be launched with the
heap data provided to it the same way as Intent#ACTION_SEND
. Note that to
match, the activity must support this action and a MIME type of "*/*".
Constant Value: "android.app.action.REPORT_HEAP_LIMIT"
LOCK_TASK_MODE_LOCKED
public static final int LOCK_TASK_MODE_LOCKED
Full lock task mode is active.
Constant Value: 1 (0x00000001)
LOCK_TASK_MODE_NONE
public static final int LOCK_TASK_MODE_NONE
Lock task mode is not active.
Constant Value: 0 (0x00000000)
LOCK_TASK_MODE_PINNED
public static final int LOCK_TASK_MODE_PINNED
App pinning mode is active.
Constant Value: 2 (0x00000002)
META_HOME_ALTERNATE
public static final 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. The package named here must be
signed with the same certificate as the one declaring the <meta-data>
.
Constant Value: "android.app.home.alternate"
MOVE_TASK_NO_USER_ACTION
public static final 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.
Constant Value: 2 (0x00000002)
MOVE_TASK_WITH_HOME
public static final 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.
Constant Value: 1 (0x00000001)
RECENT_IGNORE_UNAVAILABLE
public static final int RECENT_IGNORE_UNAVAILABLE
Provides a list that does not contain any recent tasks that currently are not available to the user.
Constant Value: 2 (0x00000002)
RECENT_WITH_EXCLUDED
public static final int RECENT_WITH_EXCLUDED
Flag for use with getRecentTasks(int, int)
: return all tasks, even those
that have set their
Intent.FLAG_ACTIVITY_EXCLUDE_FROM_RECENTS
flag.
Constant Value: 1 (0x00000001)
Public methods
addAppTask
public int addAppTask (Activity activity, Intent intent, ActivityManager.TaskDescription description, Bitmap thumbnail)
Add a new AppTask
for the calling application. This will create a new
recents entry that is added to the end of all existing recents.
Parameters | |
---|---|
activity |
Activity : The activity that is adding the entry. This is used to help determine
the context that the new recents entry will be in.
This value cannot be null . |
intent |
Intent : The Intent that describes the recents entry. This is the same Intent that
you would have used to launch the activity for it. In generally you will want to set
both Intent#FLAG_ACTIVITY_NEW_DOCUMENT and
Intent#FLAG_ACTIVITY_RETAIN_IN_RECENTS ; the latter is required since this recents
entry will exist without an activity, so it doesn't make sense to not retain it when
its activity disappears. The given Intent here also must have an explicit ComponentName
set on it.
This value cannot be null . |
description |
ActivityManager.TaskDescription : Optional additional description information.
This value may be null . |
thumbnail |
Bitmap : Thumbnail to use for the recents entry. Should be the size given by
getAppTaskThumbnailSize() . If the bitmap is not that exact size, it will be
recreated in your process, probably in a way you don't like, before the recents entry
is added.
This value cannot be null . |
Returns | |
---|---|
int |
Returns the task id of the newly added app task, or -1 if the add failed. The most likely cause of failure is that there is no more room for more tasks for your app. |
addApplicationStartInfoCompletionListener
public void addApplicationStartInfoCompletionListener (Executor executor, Consumer<ApplicationStartInfo> listener)
Adds a callback that is notified when the ApplicationStartInfo
record of this startup
is complete. The startup is considered complete when the first frame is drawn.
The callback doesn't wait for Activity#reportFullyDrawn
to occur. Retrieve a copy
of ApplicationStartInfo
after Activity#reportFullyDrawn
is called (using this
callback or ERROR(/getHistoricalProcessStartReasons)
) if you need the
ERROR(/ApplicationStartInfo.START_TIMESTAMP_FULLY_DRAWN)
timestamp.
If the current start record has already been completed (that is, the process is not currently
starting), the callback will be invoked immediately on the specified executor with the
previously completed ApplicationStartInfo
record.
Callback will be called at most once and removed automatically after being triggered.
Note: callback is asynchronous and should be made from a background thread.
Parameters | |
---|---|
executor |
Executor : The executor on which the listener should be called.
This value cannot be null . |
listener |
Consumer : Callback to be called when collection of ApplicationStartInfo is
complete. Will replace existing listener if one is already attached.
This value cannot be null . |
Throws | |
---|---|
IllegalArgumentException |
if executor or listener are null. |
addStartInfoTimestamp
public void addStartInfoTimestamp (int key, long timestampNs)
Adds an optional developer supplied timestamp to the calling apps most recent
ApplicationStartInfo
. This is in addition to system recorded timestamps.
Note: any timestamps added after Activity#reportFullyDrawn
is called
are discarded.
Note: will overwrite existing timestamp if called with same key.
Parameters | |
---|---|
key |
int : Unique key for timestamp. Must be greater than
ApplicationStartInfo#START_TIMESTAMP_RESERVED_RANGE_SYSTEM and
less than or equal to
ApplicationStartInfo#START_TIMESTAMP_RESERVED_RANGE_DEVELOPER .
Will thow IllegalArgumentException if not in range.
Value is between ApplicationStartInfo.START_TIMESTAMP_RESERVED_RANGE_DEVELOPER_START and ApplicationStartInfo.START_TIMESTAMP_RESERVED_RANGE_DEVELOPER inclusive |
timestampNs |
long : Clock monotonic time in nanoseconds of event to be recorded. |
appNotResponding
public void appNotResponding (String reason)
Method for the app to tell system that it's wedged and would like to trigger an ANR.
Parameters | |
---|---|
reason |
String : The description of that what happened
This value cannot be null . |
clearApplicationUserData
public boolean clearApplicationUserData ()
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. It also revokes all runtime permissions that the app has acquired, clears all notifications and removes all Uri grants related to this application.
Returns | |
---|---|
boolean |
true if the application successfully requested that the application's
data be erased; false otherwise. |
clearWatchHeapLimit
public void clearWatchHeapLimit ()
Clear a heap watch limit previously set by setWatchHeapLimit(long)
.
dumpPackageState
public void dumpPackageState (FileDescriptor fd, String packageName)
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.
Requires Manifest.permission.DUMP
Parameters | |
---|---|
fd |
FileDescriptor : 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. |
packageName |
String : The name of the package that is to be dumped. |
getAppTaskThumbnailSize
public Size getAppTaskThumbnailSize ()
Return the current design dimensions for AppTask
thumbnails, for use
with addAppTask(Activity, Intent, TaskDescription, Bitmap)
.
Returns | |
---|---|
Size |
getAppTasks
public List<ActivityManager.AppTask> getAppTasks ()
Get the list of tasks associated with the calling application.
Returns | |
---|---|
List<ActivityManager.AppTask> |
The list of tasks associated with the application making this call. |
Throws | |
---|---|
|
java.lang.SecurityException |
getDeviceConfigurationInfo
public ConfigurationInfo getDeviceConfigurationInfo ()
Get the device configuration attributes.
Returns | |
---|---|
ConfigurationInfo |
getHistoricalProcessExitReasons
public List<ApplicationExitInfo> getHistoricalProcessExitReasons (String packageName, int pid, int maxNum)
Return a list of ApplicationExitInfo
records containing the reasons for the most
recent app deaths.
Note: System stores this historical information in a ring buffer and only the most recent records will be returned.
Note: In the case that this application was bound to an external service
with flag Context.BIND_EXTERNAL_SERVICE
, the process of that external
service will be included in this package's exit info.
Parameters | |
---|---|
packageName |
String : Optional, a null value means match all packages belonging to the
caller's UID. If this package belongs to another UID, you must hold
Manifest.permission.DUMP in order to retrieve it. |
pid |
int : A process ID that used to belong to this package but died later; a value
of 0 means to ignore this parameter and return all matching records.
Value is 0 or greater |
maxNum |
int : The maximum number of results to be returned; a value of 0
means to ignore this parameter and return all matching records
Value is 0 or greater |
Returns | |
---|---|
List<ApplicationExitInfo> |
a list of ApplicationExitInfo records matching the criteria, sorted in
the order from most recent to least recent.
This value cannot be null . |
getHistoricalProcessStartReasons
public List<ApplicationStartInfo> getHistoricalProcessStartReasons (int maxNum)
Return a list of ApplicationStartInfo
records containing the information about the
most recent app startups.
Records accessed using this path might include "incomplete" records such as in-progress app
starts. Accessing in-progress starts using this method lets you access start information
early to better optimize your startup path.
Note: System stores this historical information in a ring buffer and only the most recent records will be returned.
Parameters | |
---|---|
maxNum |
int : The maximum number of results to be returned; a value of 0
means to ignore this parameter and return all matching records. If fewer
records exist, all existing records will be returned.
Value is 0 or greater |
Returns | |
---|---|
List<ApplicationStartInfo> |
a list of ApplicationStartInfo records matching the criteria, sorted in
the order from most recent to least recent.
This value cannot be null . |
getLargeMemoryClass
public int getLargeMemoryClass ()
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.
This is the size of the application's Dalvik heap if it has
specified android:largeHeap="true"
in its manifest.
Returns | |
---|---|
int |
getLauncherLargeIconDensity
public int getLauncherLargeIconDensity ()
Get the preferred density of icons for the launcher. This is used when custom drawables are created (e.g., for shortcuts).
Returns | |
---|---|
int |
density in terms of DPI |
getLauncherLargeIconSize
public int getLauncherLargeIconSize ()
Get the preferred launcher icon size. This is used when custom drawables are created (e.g., for shortcuts).
Returns | |
---|---|
int |
dimensions of square icons in terms of pixels |
getLockTaskModeState
public int getLockTaskModeState ()
Return the current state of task locking. The three possible outcomes
are LOCK_TASK_MODE_NONE
, LOCK_TASK_MODE_LOCKED
and LOCK_TASK_MODE_PINNED
.
Returns | |
---|---|
int |
See also:
getMemoryClass
public int getMemoryClass ()
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 devices with more memory may return 24 or even higher numbers.
Returns | |
---|---|
int |
getMemoryInfo
public void getMemoryInfo (ActivityManager.MemoryInfo outInfo)
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(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.
Parameters | |
---|---|
outInfo |
ActivityManager.MemoryInfo |
getMyMemoryState
public static void getMyMemoryState (ActivityManager.RunningAppProcessInfo outState)
Return global memory state information for the calling process. This
does not fill in all fields of the RunningAppProcessInfo
. The
only fields that will be filled in are
RunningAppProcessInfo#pid
,
RunningAppProcessInfo#uid
,
RunningAppProcessInfo#lastTrimLevel
,
RunningAppProcessInfo#importance
,
RunningAppProcessInfo#lru
, and
RunningAppProcessInfo#importanceReasonCode
.
Parameters | |
---|---|
outState |
ActivityManager.RunningAppProcessInfo |
getProcessMemoryInfo
public MemoryInfo[] getProcessMemoryInfo (int[] pids)
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.
As of Android Q
, for regular apps this method
will only return information about the memory info for the processes running as the
caller's uid; no other process memory info is available and will be zero.
Also of Android Q
the sample rate allowed
by this API is significantly limited, if called faster the limit you will receive the
same data as the previous call.
Parameters | |
---|---|
pids |
int : The pids of the processes whose memory usage is to be
retrieved. |
Returns | |
---|---|
MemoryInfo[] |
Returns an array of memory information, one for each requested pid. |
getProcessesInErrorState
public List<ActivityManager.ProcessErrorStateInfo> getProcessesInErrorState ()
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.
As of Android TIRAMISU
, for regular apps
this method will only return ProcessErrorStateInfo
records for the processes running
as the caller's uid, unless the caller has the permission
Manifest.permission.DUMP
.
Returns | |
---|---|
List<ActivityManager.ProcessErrorStateInfo> |
Returns a list of ProcessErrorStateInfo records, or null if there are no
current error conditions (it will not return an empty list). This list ordering is not
specified. |
getRecentTasks
public List<ActivityManager.RecentTaskInfo> getRecentTasks (int maxNum, int flags)
This method was deprecated
in API level 21.
As of Build.VERSION_CODES.LOLLIPOP
, this method is
no longer available to third party applications: the introduction of
document-centric recents means
it can leak personal information to the caller. For backwards compatibility,
it will still return a small subset of its data: at least the caller's
own tasks (though see getAppTasks()
for the correct supported
way to retrieve that information), and possibly some other tasks
such as home that are known to not be sensitive.
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.
Parameters | |
---|---|
maxNum |
int : 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. |
flags |
int : Information about what to return. May be any combination
of RECENT_WITH_EXCLUDED and RECENT_IGNORE_UNAVAILABLE . |
Returns | |
---|---|
List<ActivityManager.RecentTaskInfo> |
Returns a list of RecentTaskInfo records describing each of the recent tasks. |
Throws | |
---|---|
SecurityException |
getRunningAppProcesses
public List<ActivityManager.RunningAppProcessInfo> getRunningAppProcesses ()
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 | |
---|---|
List<ActivityManager.RunningAppProcessInfo> |
Returns a list of RunningAppProcessInfo records, or null if there are no running processes (it will not return an empty list). This list ordering is not specified. |
getRunningServiceControlPanel
public PendingIntent getRunningServiceControlPanel (ComponentName service)
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.
Parameters | |
---|---|
service |
ComponentName |
Returns | |
---|---|
PendingIntent |
Throws | |
---|---|
SecurityException |
getRunningServices
public List<ActivityManager.RunningServiceInfo> getRunningServices (int maxNum)
This method was deprecated
in API level 26.
As of Build.VERSION_CODES.O
, this method
is no longer available to third party applications. For backwards compatibility,
it will still return the caller's own services.
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.
Parameters | |
---|---|
maxNum |
int : The maximum number of entries to return in the list. The
actual number returned may be smaller, depending on how many services
are running. |
Returns | |
---|---|
List<ActivityManager.RunningServiceInfo> |
Returns a list of RunningServiceInfo records describing each of the running tasks. |
Throws | |
---|---|
SecurityException |
getRunningTasks
public List<ActivityManager.RunningTaskInfo> getRunningTasks (int maxNum)
This method was deprecated
in API level 21.
As of Build.VERSION_CODES.LOLLIPOP
, this method
is no longer available to third party
applications: the introduction of document-centric recents means
it can leak person information to the caller. For backwards compatibility,
it will still return a small subset of its data: at least the caller's
own tasks, and possibly some other tasks
such as home that are known to not be sensitive.
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.
Parameters | |
---|---|
maxNum |
int : 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. |
Returns | |
---|---|
List<ActivityManager.RunningTaskInfo> |
Returns a list of RunningTaskInfo records describing each of the running tasks. |
Throws | |
---|---|
SecurityException |
isActivityStartAllowedOnDisplay
public boolean isActivityStartAllowedOnDisplay (Context context, int displayId, Intent intent)
Check if the context is allowed to start an activity on specified display. Some launch
restrictions may apply to secondary displays that are private, virtual, or owned by the
system, in which case an activity start may throw a SecurityException
. Call this
method prior to starting an activity on a secondary display to check if the current context
has access to it.
Parameters | |
---|---|
context |
Context : Source context, from which an activity will be started.
This value cannot be null . |
displayId |
int : Target display id. |
intent |
Intent : Intent used to launch an activity.
This value cannot be null . |
Returns | |
---|---|
boolean |
true if a call to start an activity on the target display is allowed for the
provided context and no SecurityException will be thrown, false otherwise. |
isBackgroundRestricted
public boolean isBackgroundRestricted ()
Query whether the user has enabled background restrictions for this app.
The user may chose to do this, if they see that an app is consuming an unreasonable amount of battery while in the background.
If true, any work that the app tries to do will be aggressively restricted while it is in the background. At a minimum, jobs and alarms will not execute and foreground services cannot be started unless an app activity is in the foreground.
Note that these restrictions stay in effect even when the device is charging.
Returns | |
---|---|
boolean |
true if user has enforced background restrictions for this app, false otherwise. |
isInLockTaskMode
public boolean isInLockTaskMode ()
This method was deprecated
in API level 23.
Use getLockTaskModeState()
instead.
Return whether currently in lock task mode. When in this mode no new tasks can be created or switched to.
Returns | |
---|---|
boolean |
See also:
isLowMemoryKillReportSupported
public static boolean isLowMemoryKillReportSupported ()
Returns | |
---|---|
boolean |
Whether or not the low memory kill will be reported in
getHistoricalProcessExitReasons(String, int, int) . |
See also:
isLowRamDevice
public boolean isLowRamDevice ()
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 with 1GB or less of RAM. This is mostly intended to be used by apps to determine whether they should turn off certain features that require more RAM.
Returns | |
---|---|
boolean |
isRunningInTestHarness
public static boolean isRunningInTestHarness ()
This method was deprecated
in API level 29.
this method is false for all user builds. Users looking to check if their device
is running in a device farm should see isRunningInUserTestHarness()
.
Returns "true" if device is running in a test harness.
Returns | |
---|---|
boolean |
isRunningInUserTestHarness
public static boolean isRunningInUserTestHarness ()
Returns "true" if the device is running in Test Harness Mode.
Test Harness Mode is a feature that allows devices to run without human interaction in a device farm/testing harness (such as Firebase Test Lab). You should check this method if you want your app to behave differently when running in a test harness to skip setup screens that would impede UI testing. e.g. a keyboard application that has a full screen setup page for the first time it is launched.
Note that you should not use this to determine whether or not your app is running an instrumentation test, as it is not set for a standard device running a test.
Returns | |
---|---|
boolean |
isUserAMonkey
public static boolean isUserAMonkey ()
Returns "true" if the user interface is currently being messed with by a monkey.
Returns | |
---|---|
boolean |
killBackgroundProcesses
public void killBackgroundProcesses (String packageName)
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.
On devices that run Android 14 or higher, third party applications can only use this API to kill their own processes.
Requires
Manifest.permission.KILL_BACKGROUND_PROCESSES
Parameters | |
---|---|
packageName |
String : The name of the package whose processes are to
be killed. |
moveTaskToFront
public void moveTaskToFront (int taskId, int flags, Bundle options)
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 Manifest.permission.REORDER_TASKS
Parameters | |
---|---|
taskId |
int : The identifier of the task to be moved, as found in
RunningTaskInfo or RecentTaskInfo . |
flags |
int : Additional operational flags.
Value is either 0 or a combination of MOVE_TASK_WITH_HOME , and MOVE_TASK_NO_USER_ACTION |
options |
Bundle : Additional options for the operation, either null or
as per Context.startActivity(Intent, Bundle) . |
moveTaskToFront
public void moveTaskToFront (int taskId, int flags)
Equivalent to calling moveTaskToFront(int, int, android.os.Bundle)
with a null options argument.
Requires Manifest.permission.REORDER_TASKS
Parameters | |
---|---|
taskId |
int : The identifier of the task to be moved, as found in
RunningTaskInfo or RecentTaskInfo . |
flags |
int : Additional operational flags.
Value is either 0 or a combination of MOVE_TASK_WITH_HOME , and MOVE_TASK_NO_USER_ACTION |
removeApplicationStartInfoCompletionListener
public void removeApplicationStartInfoCompletionListener (Consumer<ApplicationStartInfo> listener)
Removes the provided callback set by addApplicationStartInfoCompletionListener(Executor, Consumer)
.
Parameters | |
---|---|
listener |
Consumer : This value cannot be null . |
restartPackage
public void restartPackage (String packageName)
This method was deprecated
in API level 15.
This is now just a wrapper for
killBackgroundProcesses(java.lang.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.
Parameters | |
---|---|
packageName |
String |
setProcessStateSummary
public void setProcessStateSummary (byte[] state)
Set custom state data for this process. It will be included in the record of
ApplicationExitInfo
on the death of the current calling process; the new process
of the app can retrieve this state data by calling
ApplicationExitInfo.getProcessStateSummary()
on the record returned by
getHistoricalProcessExitReasons(String, int, int)
.
This would be useful for the calling app to save its stateful data: if it's killed later for any reason, the new process of the app can know what the previous process of the app was doing. For instance, you could use this to encode the current level in a game, or a set of features/experiments that were enabled. Later you could analyze under what circumstances the app tends to crash or use too much memory. However, it's not suggested to rely on this to restore the applications previous UI state or so, it's only meant for analyzing application healthy status.
System might decide to throttle the calls to this API; so call this API in a reasonable
manner, excessive calls to this API could result a RuntimeException
.
Parameters | |
---|---|
state |
byte : The state data. To be advised, DO NOT include sensitive information/data
(PII, SPII, or other sensitive user data) here. Maximum length is 128 bytes.
This value may be null . |
setVrThread
public static void setVrThread (int tid)
Enable more aggressive scheduling for latency-sensitive low-runtime VR threads. Only one thread can be a VR thread in a process at a time, and that thread may be subject to restrictions on the amount of time it can run. If persistent VR mode is set, whatever thread has been granted aggressive scheduling via this method will return to normal operation, and calling this method will do nothing while persistent VR mode is enabled. To reset the VR thread for an application, a tid of 0 can be passed.
Parameters | |
---|---|
tid |
int : tid of the VR thread |
See also:
setWatchHeapLimit
public void setWatchHeapLimit (long pssSize)
Request that the system start watching for the calling process to exceed a pss
size as given here. Once called, the system will look for any occasions where it
sees the associated process with a larger pss size and, when this happens, automatically
pull a heap dump from it and allow the user to share the data. Note that this request
continues running even if the process is killed and restarted. To remove the watch,
use clearWatchHeapLimit()
.
This API only works if the calling process has been marked as
ApplicationInfo#FLAG_DEBUGGABLE
or this is running on a debuggable
(userdebug or eng) build.
Callers can optionally implement ACTION_REPORT_HEAP_LIMIT
to directly
handle heap limit reports themselves.
Parameters | |
---|---|
pssSize |
long : The size in bytes to set the limit at. |
Content and code samples on this page are subject to the licenses described in the Content License. Java and OpenJDK are trademarks or registered trademarks of Oracle and/or its affiliates.
Last updated 2024-07-18 UTC.