java.lang.Object | |
↳ | android.content.Context |
Known Direct Subclasses |
Interface to global information about an application environment. This is an abstract class whose implementation is provided by the Android system. It allows access to application-specific resources and classes, as well as up-calls for application-level operations such as launching activities, broadcasting and receiving intents, etc.
Constants | |||||||||||
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String | ACCESSIBILITY_SERVICE | Use with getSystemService(String) to retrieve a
AccessibilityManager for giving the user
feedback for UI events through the registered event listeners. |
|||||||||
String | ACCOUNT_SERVICE | Use with getSystemService(String) to retrieve a
AccountManager for receiving intents at a
time of your choosing. |
|||||||||
String | ACTIVITY_SERVICE | Use with getSystemService(String) to retrieve a
ActivityManager for interacting with the global
system state. |
|||||||||
String | ALARM_SERVICE | Use with getSystemService(String) to retrieve a
AlarmManager for receiving intents at a
time of your choosing. |
|||||||||
String | AUDIO_SERVICE | Use with getSystemService(String) to retrieve a
AudioManager for handling management of volume,
ringer modes and audio routing. |
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int | BIND_AUTO_CREATE | Flag for bindService(Intent, ServiceConnection, int) : automatically create the service as long
as the binding exists. |
|||||||||
int | BIND_DEBUG_UNBIND | Flag for bindService(Intent, ServiceConnection, int) : include debugging help for mismatched
calls to unbind. |
|||||||||
int | BIND_NOT_FOREGROUND | Flag for bindService(Intent, ServiceConnection, int) : don't allow this binding to raise
the target service's process to the foreground scheduling priority. |
|||||||||
String | CLIPBOARD_SERVICE | Use with getSystemService(String) to retrieve a
ClipboardManager for accessing and modifying
the contents of the global clipboard. |
|||||||||
String | CONNECTIVITY_SERVICE | Use with getSystemService(String) to retrieve a ConnectivityManager for handling management of
network connections. |
|||||||||
int | CONTEXT_IGNORE_SECURITY | Flag for use with createPackageContext(String, int) : ignore any security
restrictions on the Context being requested, allowing it to always
be loaded. |
|||||||||
int | CONTEXT_INCLUDE_CODE | Flag for use with createPackageContext(String, int) : include the application
code with the context. |
|||||||||
int | CONTEXT_RESTRICTED | Flag for use with createPackageContext(String, int) : a restricted context may
disable specific features. |
|||||||||
String | DEVICE_POLICY_SERVICE | Use with getSystemService(String) to retrieve a
DevicePolicyManager for working with global
device policy management. |
|||||||||
String | DROPBOX_SERVICE | Use with getSystemService(String) to retrieve a
DropBoxManager instance for recording
diagnostic logs. |
|||||||||
String | INPUT_METHOD_SERVICE | Use with getSystemService(String) to retrieve a
InputMethodManager for accessing input
methods. |
|||||||||
String | KEYGUARD_SERVICE | Use with getSystemService(String) to retrieve a
NotificationManager for controlling keyguard. |
|||||||||
String | LAYOUT_INFLATER_SERVICE | Use with getSystemService(String) to retrieve a
LayoutInflater for inflating layout resources in this
context. |
|||||||||
String | LOCATION_SERVICE | Use with getSystemService(String) to retrieve a LocationManager for controlling location
updates. |
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int | MODE_APPEND | File creation mode: for use with openFileOutput(String, int) , if the file
already exists then write data to the end of the existing file
instead of erasing it. |
|||||||||
int | MODE_PRIVATE | File creation mode: the default mode, where the created file can only be accessed by the calling application (or all applications sharing the same user ID). | |||||||||
int | MODE_WORLD_READABLE | File creation mode: allow all other applications to have read access to the created file. | |||||||||
int | MODE_WORLD_WRITEABLE | File creation mode: allow all other applications to have write access to the created file. | |||||||||
String | NOTIFICATION_SERVICE | Use with getSystemService(String) to retrieve a
NotificationManager for informing the user of
background events. |
|||||||||
String | POWER_SERVICE | Use with getSystemService(String) to retrieve a
PowerManager for controlling power management,
including "wake locks," which let you keep the device on while
you're running long tasks. |
|||||||||
String | SEARCH_SERVICE | Use with getSystemService(String) to retrieve a SearchManager for handling searches. |
|||||||||
String | SENSOR_SERVICE | Use with getSystemService(String) to retrieve a SensorManager for accessing sensors. |
|||||||||
String | TELEPHONY_SERVICE | Use with getSystemService(String) to retrieve a
TelephonyManager for handling management the
telephony features of the device. |
|||||||||
String | UI_MODE_SERVICE | Use with getSystemService(String) to retrieve a
UiModeManager for controlling UI modes. |
|||||||||
String | VIBRATOR_SERVICE | Use with getSystemService(String) to retrieve a Vibrator for interacting with the vibration hardware. |
|||||||||
String | WALLPAPER_SERVICE | Use with getSystemService(String) to retrieve a
com.android.server.WallpaperService for accessing wallpapers. |
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String | WIFI_SERVICE | Use with getSystemService(String) to retrieve a WifiManager for handling management of
Wi-Fi access. |
|||||||||
String | WINDOW_SERVICE | Use with getSystemService(String) to retrieve a
WindowManager for accessing the system's window
manager. |
Public Constructors | |||||||||||
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Public Methods | |||||||||||
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Connect to an application service, creating it if needed.
| |||||||||||
Determine whether the calling process of an IPC or you have been
granted a particular permission.
| |||||||||||
Determine whether the calling process of an IPC or you has been granted
permission to access a specific URI.
| |||||||||||
Determine whether the calling process of an IPC you are handling has been
granted a particular permission.
| |||||||||||
Determine whether the calling process and user ID has been
granted permission to access a specific URI.
| |||||||||||
Determine whether the given permission is allowed for a particular
process and user ID running in the system.
| |||||||||||
Determine whether a particular process and user ID has been granted
permission to access a specific URI.
| |||||||||||
Check both a Uri and normal permission.
| |||||||||||
This method is deprecated.
Use
WallpaperManager.clear() instead.
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Return a new Context object for the given application name.
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Returns an array of strings naming the private databases associated with
this Context's application package.
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Delete an existing private SQLiteDatabase associated with this Context's
application package.
| |||||||||||
Delete the given private file associated with this Context's
application package.
| |||||||||||
If neither you nor the calling process of an IPC you are
handling has been granted a particular permission, throw a
SecurityException . | |||||||||||
If the calling process of an IPC or you has not been
granted permission to access a specific URI, throw
SecurityException . | |||||||||||
If the calling process of an IPC you are handling has not been
granted a particular permission, throw a
SecurityException . | |||||||||||
If the calling process and user ID has not been granted
permission to access a specific URI, throw
SecurityException . | |||||||||||
If the given permission is not allowed for a particular process
and user ID running in the system, throw a
SecurityException . | |||||||||||
If a particular process and user ID has not been granted
permission to access a specific URI, throw
SecurityException . | |||||||||||
Enforce both a Uri and normal permission.
| |||||||||||
Returns an array of strings naming the private files associated with
this Context's application package.
| |||||||||||
Return the context of the single, global Application object of the
current process.
| |||||||||||
Return the full application info for this context's package.
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Return an AssetManager instance for your application's package.
| |||||||||||
Returns the absolute path to the application specific cache directory
on the filesystem.
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Return a class loader you can use to retrieve classes in this package.
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Return a ContentResolver instance for your application's package.
| |||||||||||
Returns the absolute path on the filesystem where a database created with
openOrCreateDatabase(String, int, SQLiteDatabase.CursorFactory) is stored. | |||||||||||
Retrieve, creating if needed, a new directory in which the application
can place its own custom data files.
| |||||||||||
Returns the absolute path to the directory on the external filesystem
(that is somewhere on
Environment.getExternalStorageDirectory() where the application can
place cache files it owns. | |||||||||||
Returns the absolute path to the directory on the external filesystem
(that is somewhere on
Environment.getExternalStorageDirectory() ) where the application can
place persistent files it owns. | |||||||||||
Returns the absolute path on the filesystem where a file created with
openFileOutput(String, int) is stored. | |||||||||||
Returns the absolute path to the directory on the filesystem where
files created with
openFileOutput(String, int) are stored. | |||||||||||
Return the Looper for the main thread of the current process.
| |||||||||||
Return the full path to this context's primary Android package.
| |||||||||||
Return PackageManager instance to find global package information.
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Return the name of this application's package.
| |||||||||||
Return the full path to this context's primary Android package.
| |||||||||||
Return a Resources instance for your application's package.
| |||||||||||
Retrieve and hold the contents of the preferences file 'name', returning
a SharedPreferences through which you can retrieve and modify its
values.
| |||||||||||
Return a localized formatted string from the application's package's
default string table, substituting the format arguments as defined in
Formatter and format(String, Object...) . | |||||||||||
Return a localized string from the application's package's
default string table.
| |||||||||||
Return the handle to a system-level service by name.
| |||||||||||
Return a localized, styled CharSequence from the application's package's
default string table.
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Return the Theme object associated with this Context.
| |||||||||||
This method is deprecated.
Use
WallpaperManager.get() instead.
| |||||||||||
This method is deprecated.
Use
WallpaperManager.getDesiredMinimumHeight() instead.
| |||||||||||
This method is deprecated.
Use
WallpaperManager.getDesiredMinimumWidth() instead.
| |||||||||||
Grant permission to access a specific Uri to another package, regardless
of whether that package has general permission to access the Uri's
content provider.
| |||||||||||
Indicates whether this Context is restricted.
| |||||||||||
Retrieve styled attribute information in this Context's theme.
| |||||||||||
Retrieve styled attribute information in this Context's theme.
| |||||||||||
Retrieve styled attribute information in this Context's theme.
| |||||||||||
Retrieve styled attribute information in this Context's theme.
| |||||||||||
Open a private file associated with this Context's application package
for reading.
| |||||||||||
Open a private file associated with this Context's application package
for writing.
| |||||||||||
Open a new private SQLiteDatabase associated with this Context's
application package.
| |||||||||||
This method is deprecated.
Use
WallpaperManager.peek() instead.
| |||||||||||
Register to receive intent broadcasts, to run in the context of
scheduler.
| |||||||||||
Register a BroadcastReceiver to be run in the main activity thread.
| |||||||||||
Remove the data previously sent with
sendStickyBroadcast(Intent) ,
so that it is as if the sticky broadcast had never happened. | |||||||||||
Remove all permissions to access a particular content provider Uri
that were previously added with
grantUriPermission(String, Uri, int) . | |||||||||||
Broadcast the given intent to all interested BroadcastReceivers.
| |||||||||||
Broadcast the given intent to all interested BroadcastReceivers, allowing
an optional required permission to be enforced.
| |||||||||||
Version of
sendBroadcast(Intent) that allows you to
receive data back from the broadcast. | |||||||||||
Broadcast the given intent to all interested BroadcastReceivers, delivering
them one at a time to allow more preferred receivers to consume the
broadcast before it is delivered to less preferred receivers.
| |||||||||||
Perform a
sendBroadcast(Intent) that is "sticky," meaning the
Intent you are sending stays around after the broadcast is complete,
so that others can quickly retrieve that data through the return
value of registerReceiver(BroadcastReceiver, IntentFilter) . | |||||||||||
Version of
sendStickyBroadcast(Intent) that allows you to
receive data back from the broadcast. | |||||||||||
Set the base theme for this context.
| |||||||||||
This method is deprecated.
Use
WallpaperManager.set() instead.
| |||||||||||
This method is deprecated.
Use
WallpaperManager.set() instead.
| |||||||||||
Launch a new activity.
| |||||||||||
Start executing an
Instrumentation class. | |||||||||||
Like
startActivity(Intent) , but taking a IntentSender
to start. | |||||||||||
Request that a given application service be started.
| |||||||||||
Request that a given application service be stopped.
| |||||||||||
Disconnect from an application service.
| |||||||||||
Unregister a previously registered BroadcastReceiver.
|
[Expand]
Inherited Methods | |||||||||||
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From class java.lang.Object
|
Use with getSystemService(String)
to retrieve a
AccessibilityManager
for giving the user
feedback for UI events through the registered event listeners.
Use with getSystemService(String)
to retrieve a
AccountManager
for receiving intents at a
time of your choosing.
Use with getSystemService(String)
to retrieve a
ActivityManager
for interacting with the global
system state.
Use with getSystemService(String)
to retrieve a
AlarmManager
for receiving intents at a
time of your choosing.
Use with getSystemService(String)
to retrieve a
AudioManager
for handling management of volume,
ringer modes and audio routing.
Flag for bindService(Intent, ServiceConnection, int)
: automatically create the service as long
as the binding exists. Note that while this will create the service,
its onStart(Intent, int)
method will still only be called due to an
explicit call to startService(Intent)
. Even without that, though,
this still provides you with access to the service object while the
service is created.
Specifying this flag also tells the system to treat the service as being as important as your own process -- that is, when deciding which process should be killed to free memory, the service will only be considered a candidate as long as the processes of any such bindings is also a candidate to be killed. This is to avoid situations where the service is being continually created and killed due to low memory.
Flag for bindService(Intent, ServiceConnection, int)
: include debugging help for mismatched
calls to unbind. When this flag is set, the callstack of the following
unbindService(ServiceConnection)
call is retained, to be printed if a later
incorrect unbind call is made. Note that doing this requires retaining
information about the binding that was made for the lifetime of the app,
resulting in a leak -- this should only be used for debugging.
Flag for bindService(Intent, ServiceConnection, int)
: don't allow this binding to raise
the target service's process to the foreground scheduling priority.
It will still be raised to the at least the same memory priority
as the client (so that its process will not be killable in any
situation where the client is not killable), but for CPU scheduling
purposes it may be left in the background. This only has an impact
in the situation where the binding client is a foreground process
and the target service is in a background process.
Use with getSystemService(String)
to retrieve a
ClipboardManager
for accessing and modifying
the contents of the global clipboard.
Use with getSystemService(String)
to retrieve a ConnectivityManager
for handling management of
network connections.
Flag for use with createPackageContext(String, int)
: ignore any security
restrictions on the Context being requested, allowing it to always
be loaded. For use with CONTEXT_INCLUDE_CODE
to allow code
to be loaded into a process even when it isn't safe to do so. Use
with extreme care!
Flag for use with createPackageContext(String, int)
: include the application
code with the context. This means loading code into the caller's
process, so that getClassLoader()
can be used to instantiate
the application's classes. Setting this flags imposes security
restrictions on what application context you can access; if the
requested application can not be safely loaded into your process,
java.lang.SecurityException will be thrown. If this flag is not set,
there will be no restrictions on the packages that can be loaded,
but getClassLoader()
will always return the default system
class loader.
Flag for use with createPackageContext(String, int)
: a restricted context may
disable specific features. For instance, a View associated with a restricted
context would ignore particular XML attributes.
Use with getSystemService(String)
to retrieve a
DevicePolicyManager
for working with global
device policy management.
Use with getSystemService(String)
to retrieve a
DropBoxManager
instance for recording
diagnostic logs.
Use with getSystemService(String)
to retrieve a
InputMethodManager
for accessing input
methods.
Use with getSystemService(String)
to retrieve a
NotificationManager
for controlling keyguard.
Use with getSystemService(String)
to retrieve a
LayoutInflater
for inflating layout resources in this
context.
Use with getSystemService(String)
to retrieve a LocationManager
for controlling location
updates.
File creation mode: for use with openFileOutput(String, int)
, if the file
already exists then write data to the end of the existing file
instead of erasing it.
File creation mode: the default mode, where the created file can only be accessed by the calling application (or all applications sharing the same user ID).
File creation mode: allow all other applications to have read access to the created file.
File creation mode: allow all other applications to have write access to the created file.
Use with getSystemService(String)
to retrieve a
NotificationManager
for informing the user of
background events.
Use with getSystemService(String)
to retrieve a
PowerManager
for controlling power management,
including "wake locks," which let you keep the device on while
you're running long tasks.
Use with getSystemService(String)
to retrieve a SearchManager
for handling searches.
Use with getSystemService(String)
to retrieve a SensorManager
for accessing sensors.
Use with getSystemService(String)
to retrieve a
TelephonyManager
for handling management the
telephony features of the device.
Use with getSystemService(String)
to retrieve a
UiModeManager
for controlling UI modes.
Use with getSystemService(String)
to retrieve a Vibrator
for interacting with the vibration hardware.
Use with getSystemService(String)
to retrieve a
com.android.server.WallpaperService for accessing wallpapers.
Use with getSystemService(String)
to retrieve a WifiManager
for handling management of
Wi-Fi access.
Use with getSystemService(String)
to retrieve a
WindowManager
for accessing the system's window
manager.
Connect to an application service, creating it if needed. This defines a dependency between your application and the service. The given conn will receive the service object when its created and be told if it dies and restarts. The service will be considered required by the system only for as long as the calling context exists. For example, if this Context is an Activity that is stopped, the service will not be required to continue running until the Activity is resumed.
This function will throw SecurityException
if you do not
have permission to bind to the given service.
Note: this method can not be called from an
BroadcastReceiver
component. A pattern you can use to
communicate from an BroadcastReceiver to a Service is to call
startService(Intent)
with the arguments containing the command to be
sent, with the service calling its
stopSelf(int)
method when done executing
that command. See the API demo App/Service/Service Start Arguments
Controller for an illustration of this. It is okay, however, to use
this method from an BroadcastReceiver that has been registered with
registerReceiver(BroadcastReceiver, IntentFilter)
, since the lifetime of this BroadcastReceiver
is tied to another object (the one that registered it).
service | Identifies the service to connect to. The Intent may
specify either an explicit component name, or a logical
description (action, category, etc) to match an
IntentFilter published by a service. |
---|---|
conn | Receives information as the service is started and stopped. |
flags | Operation options for the binding. May be 0 or
BIND_AUTO_CREATE . |
SecurityException |
Determine whether the calling process of an IPC or you have been
granted a particular permission. This is the same as
checkCallingPermission(String)
, except it grants your own permissions
if you are not currently processing an IPC. Use with care!
permission | The name of the permission being checked. |
---|
PERMISSION_GRANTED
if the calling
pid/uid is allowed that permission, or
PERMISSION_DENIED
if it is not.Determine whether the calling process of an IPC or you has been granted
permission to access a specific URI. This is the same as
checkCallingUriPermission(Uri, int)
, except it grants your own permissions
if you are not currently processing an IPC. Use with care!
uri | The uri that is being checked. |
---|---|
modeFlags | The type of access to grant. May be one or both of
Intent.FLAG_GRANT_READ_URI_PERMISSION or
Intent.FLAG_GRANT_WRITE_URI_PERMISSION . |
PERMISSION_GRANTED
if the caller
is allowed to access that uri, or
PERMISSION_DENIED
if it is not.Determine whether the calling process of an IPC you are handling has been
granted a particular permission. This is basically the same as calling
checkPermission(String, int, int)
with the pid and uid returned
by getCallingPid()
and
getCallingUid()
. One important difference
is that if you are not currently processing an IPC, this function
will always fail. This is done to protect against accidentally
leaking permissions; you can use checkCallingOrSelfPermission(String)
to avoid this protection.
permission | The name of the permission being checked. |
---|
PERMISSION_GRANTED
if the calling
pid/uid is allowed that permission, or
PERMISSION_DENIED
if it is not.Determine whether the calling process and user ID has been
granted permission to access a specific URI. This is basically
the same as calling checkUriPermission(Uri, int, int, int)
with the pid and uid returned by getCallingPid()
and getCallingUid()
. One important difference is
that if you are not currently processing an IPC, this function
will always fail.
uri | The uri that is being checked. |
---|---|
modeFlags | The type of access to grant. May be one or both of
Intent.FLAG_GRANT_READ_URI_PERMISSION or
Intent.FLAG_GRANT_WRITE_URI_PERMISSION . |
PERMISSION_GRANTED
if the caller
is allowed to access that uri, or
PERMISSION_DENIED
if it is not.Determine whether the given permission is allowed for a particular process and user ID running in the system.
permission | The name of the permission being checked. |
---|---|
pid | The process ID being checked against. Must be > 0. |
uid | The user ID being checked against. A uid of 0 is the root user, which will pass every permission check. |
PERMISSION_GRANTED
if the given
pid/uid is allowed that permission, or
PERMISSION_DENIED
if it is not.Determine whether a particular process and user ID has been granted permission to access a specific URI. This only checks for permissions that have been explicitly granted -- if the given process/uid has more general access to the URI's content provider then this check will always fail.
uri | The uri that is being checked. |
---|---|
pid | The process ID being checked against. Must be > 0. |
uid | The user ID being checked against. A uid of 0 is the root user, which will pass every permission check. |
modeFlags | The type of access to grant. May be one or both of
Intent.FLAG_GRANT_READ_URI_PERMISSION or
Intent.FLAG_GRANT_WRITE_URI_PERMISSION . |
PERMISSION_GRANTED
if the given
pid/uid is allowed to access that uri, or
PERMISSION_DENIED
if it is not.Check both a Uri and normal permission. This allows you to perform
both checkPermission(String, int, int)
and checkUriPermission(Uri, int, int, int)
in one
call.
uri | The Uri whose permission is to be checked, or null to not do this check. |
---|---|
readPermission | The permission that provides overall read access, or null to not do this check. |
writePermission | The permission that provides overall write acess, or null to not do this check. |
pid | The process ID being checked against. Must be > 0. |
uid | The user ID being checked against. A uid of 0 is the root user, which will pass every permission check. |
modeFlags | The type of access to grant. May be one or both of
Intent.FLAG_GRANT_READ_URI_PERMISSION or
Intent.FLAG_GRANT_WRITE_URI_PERMISSION . |
PERMISSION_GRANTED
if the caller
is allowed to access that uri or holds one of the given permissions, or
PERMISSION_DENIED
if it is not.
Return a new Context object for the given application name. This Context is the same as what the named application gets when it is launched, containing the same resources and class loader. Each call to this method returns a new instance of a Context object; Context objects are not shared, however they share common state (Resources, ClassLoader, etc) so the Context instance itself is fairly lightweight.
Throws PackageManager.NameNotFoundException
if there is no
application with the given package name.
Throws SecurityException
if the Context requested
can not be loaded into the caller's process for security reasons (see
CONTEXT_INCLUDE_CODE
for more information}.
packageName | Name of the application's package. |
---|---|
flags | Option flags, one of CONTEXT_INCLUDE_CODE
or CONTEXT_IGNORE_SECURITY . |
java.lang.SecurityException | |
if there is no application with the given package name | |
PackageManager.NameNotFoundException |
Returns an array of strings naming the private databases associated with this Context's application package.
Delete an existing private SQLiteDatabase associated with this Context's application package.
name | The name (unique in the application package) of the database. |
---|
Delete the given private file associated with this Context's application package.
name | The name of the file to delete; can not contain path separators. |
---|
If neither you nor the calling process of an IPC you are
handling has been granted a particular permission, throw a
SecurityException
. This is the same as enforceCallingPermission(String, String)
, except it grants your own
permissions if you are not currently processing an IPC. Use
with care!
permission | The name of the permission being checked. |
---|---|
message | A message to include in the exception if it is thrown. |
If the calling process of an IPC or you has not been
granted permission to access a specific URI, throw SecurityException
. This is the same as enforceCallingUriPermission(Uri, int, String)
, except it grants your own
permissions if you are not currently processing an IPC. Use
with care!
uri | The uri that is being checked. |
---|---|
modeFlags | The type of access to grant. May be one or both of
Intent.FLAG_GRANT_READ_URI_PERMISSION or
Intent.FLAG_GRANT_WRITE_URI_PERMISSION . |
message | A message to include in the exception if it is thrown. |
If the calling process of an IPC you are handling has not been
granted a particular permission, throw a SecurityException
. This is basically the same as calling
enforcePermission(String, int, int, String)
with the
pid and uid returned by getCallingPid()
and getCallingUid()
. One important
difference is that if you are not currently processing an IPC,
this function will always throw the SecurityException. This is
done to protect against accidentally leaking permissions; you
can use enforceCallingOrSelfPermission(String, String)
to avoid this
protection.
permission | The name of the permission being checked. |
---|---|
message | A message to include in the exception if it is thrown. |
If the calling process and user ID has not been granted
permission to access a specific URI, throw SecurityException
. This is basically the same as calling
enforceUriPermission(Uri, int, int, int, String)
with
the pid and uid returned by getCallingPid()
and getCallingUid()
. One important difference is
that if you are not currently processing an IPC, this function
will always throw a SecurityException.
uri | The uri that is being checked. |
---|---|
modeFlags | The type of access to grant. May be one or both of
Intent.FLAG_GRANT_READ_URI_PERMISSION or
Intent.FLAG_GRANT_WRITE_URI_PERMISSION . |
message | A message to include in the exception if it is thrown. |
If the given permission is not allowed for a particular process
and user ID running in the system, throw a SecurityException
.
permission | The name of the permission being checked. |
---|---|
pid | The process ID being checked against. Must be > 0. |
uid | The user ID being checked against. A uid of 0 is the root user, which will pass every permission check. |
message | A message to include in the exception if it is thrown. |
If a particular process and user ID has not been granted
permission to access a specific URI, throw SecurityException
. This only checks for permissions that have
been explicitly granted -- if the given process/uid has more
general access to the URI's content provider then this check
will always fail.
uri | The uri that is being checked. |
---|---|
pid | The process ID being checked against. Must be > 0. |
uid | The user ID being checked against. A uid of 0 is the root user, which will pass every permission check. |
modeFlags | The type of access to grant. May be one or both of
Intent.FLAG_GRANT_READ_URI_PERMISSION or
Intent.FLAG_GRANT_WRITE_URI_PERMISSION . |
message | A message to include in the exception if it is thrown. |
Enforce both a Uri and normal permission. This allows you to perform
both enforcePermission(String, int, int, String)
and enforceUriPermission(Uri, int, int, int, String)
in one
call.
uri | The Uri whose permission is to be checked, or null to not do this check. |
---|---|
readPermission | The permission that provides overall read access, or null to not do this check. |
writePermission | The permission that provides overall write acess, or null to not do this check. |
pid | The process ID being checked against. Must be > 0. |
uid | The user ID being checked against. A uid of 0 is the root user, which will pass every permission check. |
modeFlags | The type of access to grant. May be one or both of
Intent.FLAG_GRANT_READ_URI_PERMISSION or
Intent.FLAG_GRANT_WRITE_URI_PERMISSION . |
message | A message to include in the exception if it is thrown. |
Returns an array of strings naming the private files associated with this Context's application package.
Return the context of the single, global Application object of the current process. This generally should only be used if you need a Context whose lifecycle is separate from the current context, that is tied to the lifetime of the process rather than the current component.
Consider for example how this interacts with {@ #registerReceiver(BroadcastReceiver, IntentFilter)}:
If used from an Activity context, the receiver is being registered within that activity. This means that you are expected to unregister before the activity is done being destroyed; in fact if you do not do so, the framework will clean up your leaked registration as it removes the activity and log an error. Thus, if you use the Activity context to register a receiver that is static (global to the process, not associated with an Activity instance) then that registration will be removed on you at whatever point the activity you used is destroyed.
If used from the Context returned here, the receiver is being registered with the global state associated with your application. Thus it will never be unregistered for you. This is necessary if the receiver is associated with static data, not a particular component. However using the ApplicationContext elsewhere can easily lead to serious leaks if you forget to unregister, unbind, etc.
Return the full application info for this context's package.
Return an AssetManager instance for your application's package.
Returns the absolute path to the application specific cache directory on the filesystem. These files will be ones that get deleted first when the device runs low on storage. There is no guarantee when these files will be deleted. Note: you should not rely on the system deleting these files for you; you should always have a reasonable maximum, such as 1 MB, for the amount of space you consume with cache files, and prune those files when exceeding that space.
Return a class loader you can use to retrieve classes in this package.
Return a ContentResolver instance for your application's package.
Returns the absolute path on the filesystem where a database created with
openOrCreateDatabase(String, int, SQLiteDatabase.CursorFactory)
is stored.
name | The name of the database for which you would like to get its path. |
---|
Retrieve, creating if needed, a new directory in which the application can place its own custom data files. You can use the returned File object to create and access files in this directory. Note that files created through a File object will only be accessible by your own application; you can only set the mode of the entire directory, not of individual files.
name | Name of the directory to retrieve. This is a directory that is created as part of your application data. |
---|---|
mode | Operating mode. Use 0 or MODE_PRIVATE for the
default operation, MODE_WORLD_READABLE and
MODE_WORLD_WRITEABLE to control permissions. |
Returns the absolute path to the directory on the external filesystem
(that is somewhere on Environment.getExternalStorageDirectory()
where the application can
place cache files it owns.
This is like getCacheDir()
in that these
files will be deleted when the application is uninstalled, however there
are some important differences:
getCacheDir()
.
Environment
for information in the storage state.
Returns the absolute path to the directory on the external filesystem
(that is somewhere on Environment.getExternalStorageDirectory()
) where the application can
place persistent files it owns. These files are private to the
applications, and not typically visible to the user as media.
This is like getFilesDir()
in that these
files will be deleted when the application is uninstalled, however there
are some important differences:
Environment
for information in the storage state.
Here is an example of typical code to manipulate a file in an application's private storage:
void createExternalStoragePrivateFile() { // Create a path where we will place our private file on external // storage. File file = new File(getExternalFilesDir(null), "DemoFile.jpg"); try { // Very simple code to copy a picture from the application's // resource into the external file. Note that this code does // no error checking, and assumes the picture is small (does not // try to copy it in chunks). Note that if external storage is // not currently mounted this will silently fail. InputStream is = getResources().openRawResource(R.drawable.balloons); OutputStream os = new FileOutputStream(file); byte[] data = new byte[is.available()]; is.read(data); os.write(data); is.close(); os.close(); } catch (IOException e) { // Unable to create file, likely because external storage is // not currently mounted. Log.w("ExternalStorage", "Error writing " + file, e); } } void deleteExternalStoragePrivateFile() { // Get path for the file on external storage. If external // storage is not currently mounted this will fail. File file = new File(getExternalFilesDir(null), "DemoFile.jpg"); if (file != null) { file.delete(); } } boolean hasExternalStoragePrivateFile() { // Get path for the file on external storage. If external // storage is not currently mounted this will fail. File file = new File(getExternalFilesDir(null), "DemoFile.jpg"); if (file != null) { return file.exists(); } return false; }
If you supply a non-null type to this function, the returned
file will be a path to a sub-directory of the given type. Though these files
are not automatically scanned by the media scanner, you can explicitly
add them to the media database with
MediaScannerConnection.scanFile
.
Note that this is not the same as
Environment.getExternalStoragePublicDirectory()
, which provides
directories of media shared by all applications. The
directories returned here are
owned by the application, and their contents will be removed when the
application is uninstalled. Unlike
Environment.getExternalStoragePublicDirectory()
, the directory
returned here will be automatically created for you.
Here is an example of typical code to manipulate a picture in an application's private storage and add it to the media database:
void createExternalStoragePrivatePicture() { // Create a path where we will place our picture in our own private // pictures directory. Note that we don't really need to place a // picture in DIRECTORY_PICTURES, since the media scanner will see // all media in these directories; this may be useful with other // media types such as DIRECTORY_MUSIC however to help it classify // your media for display to the user. File path = getExternalFilesDir(Environment.DIRECTORY_PICTURES); File file = new File(path, "DemoPicture.jpg"); try { // Very simple code to copy a picture from the application's // resource into the external file. Note that this code does // no error checking, and assumes the picture is small (does not // try to copy it in chunks). Note that if external storage is // not currently mounted this will silently fail. InputStream is = getResources().openRawResource(R.drawable.balloons); OutputStream os = new FileOutputStream(file); byte[] data = new byte[is.available()]; is.read(data); os.write(data); is.close(); os.close(); // Tell the media scanner about the new file so that it is // immediately available to the user. MediaScannerConnection.scanFile(this, new String[] { file.toString() }, null, new MediaScannerConnection.OnScanCompletedListener() { public void onScanCompleted(String path, Uri uri) { Log.i("ExternalStorage", "Scanned " + path + ":"); Log.i("ExternalStorage", "-> uri=" + uri); } }); } catch (IOException e) { // Unable to create file, likely because external storage is // not currently mounted. Log.w("ExternalStorage", "Error writing " + file, e); } } void deleteExternalStoragePrivatePicture() { // Create a path where we will place our picture in the user's // public pictures directory and delete the file. If external // storage is not currently mounted this will fail. File path = getExternalFilesDir(Environment.DIRECTORY_PICTURES); if (path != null) { File file = new File(path, "DemoPicture.jpg"); file.delete(); } } boolean hasExternalStoragePrivatePicture() { // Create a path where we will place our picture in the user's // public pictures directory and check if the file exists. If // external storage is not currently mounted this will think the // picture doesn't exist. File path = getExternalFilesDir(Environment.DIRECTORY_PICTURES); if (path != null) { File file = new File(path, "DemoPicture.jpg"); return file.exists(); } return false; }
type | The type of files directory to return. May be null for
the root of the files directory or one of
the following Environment constants for a subdirectory:
DIRECTORY_MUSIC ,
DIRECTORY_PODCASTS ,
DIRECTORY_RINGTONES ,
DIRECTORY_ALARMS ,
DIRECTORY_NOTIFICATIONS ,
DIRECTORY_PICTURES , or
DIRECTORY_MOVIES . |
---|
Returns the absolute path on the filesystem where a file created with
openFileOutput(String, int)
is stored.
name | The name of the file for which you would like to get its path. |
---|
Returns the absolute path to the directory on the filesystem where
files created with openFileOutput(String, int)
are stored.
Return the Looper for the main thread of the current process. This is the thread used to dispatch calls to application components (activities, services, etc).
Return the full path to this context's primary Android package. The Android package is a ZIP file which contains application's primary code and assets.
Note: this is not generally useful for applications, since they should not be directly accessing the file system.
Return PackageManager instance to find global package information.
Return the name of this application's package.
Return the full path to this context's primary Android package. The Android package is a ZIP file which contains the application's primary resources.
Note: this is not generally useful for applications, since they should not be directly accessing the file system.
Return a Resources instance for your application's package.
Retrieve and hold the contents of the preferences file 'name', returning a SharedPreferences through which you can retrieve and modify its values. Only one instance of the SharedPreferences object is returned to any callers for the same name, meaning they will see each other's edits as soon as they are made.
name | Desired preferences file. If a preferences file by this name does not exist, it will be created when you retrieve an editor (SharedPreferences.edit()) and then commit changes (Editor.commit()). |
---|---|
mode | Operating mode. Use 0 or MODE_PRIVATE for the
default operation, MODE_WORLD_READABLE
and MODE_WORLD_WRITEABLE to control permissions. |
Return a localized formatted string from the application's package's
default string table, substituting the format arguments as defined in
Formatter
and format(String, Object...)
.
resId | Resource id for the format string |
---|---|
formatArgs | The format arguments that will be used for substitution. |
Return a localized string from the application's package's default string table.
resId | Resource id for the string |
---|
Return the handle to a system-level service by name. The class of the returned object varies by the requested name. Currently available names are:
WINDOW_SERVICE
("window")
WindowManager
.
LAYOUT_INFLATER_SERVICE
("layout_inflater")
LayoutInflater
for inflating layout resources
in this context.
ACTIVITY_SERVICE
("activity")
ActivityManager
for interacting with the
global activity state of the system.
POWER_SERVICE
("power")
PowerManager
for controlling power
management.
ALARM_SERVICE
("alarm")
AlarmManager
for receiving intents at the
time of your choosing.
NOTIFICATION_SERVICE
("notification")
NotificationManager
for informing the user
of background events.
KEYGUARD_SERVICE
("keyguard")
KeyguardManager
for controlling keyguard.
LOCATION_SERVICE
("location")
LocationManager
for controlling location
(e.g., GPS) updates.
SEARCH_SERVICE
("search")
SearchManager
for handling search.
VIBRATOR_SERVICE
("vibrator")
Vibrator
for interacting with the vibrator
hardware.
CONNECTIVITY_SERVICE
("connection")
ConnectivityManager
for
handling management of network connections.
WIFI_SERVICE
("wifi")
WifiManager
for management of
Wi-Fi connectivity.
INPUT_METHOD_SERVICE
("input_method")
InputMethodManager
for management of input methods.
UI_MODE_SERVICE
("uimode")
UiModeManager
for controlling UI modes.
Note: System services obtained via this API may be closely associated with the Context in which they are obtained from. In general, do not share the service objects between various different contexts (Activities, Applications, Services, Providers, etc.)
name | The name of the desired service. |
---|
WINDOW_SERVICE
WindowManager
LAYOUT_INFLATER_SERVICE
LayoutInflater
ACTIVITY_SERVICE
ActivityManager
POWER_SERVICE
PowerManager
ALARM_SERVICE
AlarmManager
NOTIFICATION_SERVICE
NotificationManager
KEYGUARD_SERVICE
KeyguardManager
LOCATION_SERVICE
LocationManager
SEARCH_SERVICE
SearchManager
SENSOR_SERVICE
SensorManager
ERROR(/#STORAGE_SERVICE)
VIBRATOR_SERVICE
Vibrator
CONNECTIVITY_SERVICE
ConnectivityManager
WIFI_SERVICE
WifiManager
AUDIO_SERVICE
AudioManager
TELEPHONY_SERVICE
TelephonyManager
INPUT_METHOD_SERVICE
InputMethodManager
UI_MODE_SERVICE
UiModeManager
Return a localized, styled CharSequence from the application's package's default string table.
resId | Resource id for the CharSequence text |
---|
Return the Theme object associated with this Context.
Grant permission to access a specific Uri to another package, regardless of whether that package has general permission to access the Uri's content provider. This can be used to grant specific, temporary permissions, typically in response to user interaction (such as the user opening an attachment that you would like someone else to display).
Normally you should use Intent.FLAG_GRANT_READ_URI_PERMISSION
or
Intent.FLAG_GRANT_WRITE_URI_PERMISSION
with the Intent being used to
start an activity instead of this function directly. If you use this
function directly, you should be sure to call
revokeUriPermission(Uri, int)
when the target should no longer be allowed
to access it.
To succeed, the content provider owning the Uri must have set the
grantUriPermissions
attribute in its manifest or included the
<grant-uri-permissions>
tag.
toPackage | The package you would like to allow to access the Uri. |
---|---|
uri | The Uri you would like to grant access to. |
modeFlags | The desired access modes. Any combination of
Intent.FLAG_GRANT_READ_URI_PERMISSION or
Intent.FLAG_GRANT_WRITE_URI_PERMISSION . |
Indicates whether this Context is restricted.
Retrieve styled attribute information in this Context's theme. See
obtainStyledAttributes(int, int[])
for more information.
Resources.NotFoundException |
---|
Retrieve styled attribute information in this Context's theme. See
obtainStyledAttributes(AttributeSet, int[], int, int)
for more information.
Retrieve styled attribute information in this Context's theme. See
obtainStyledAttributes(int[])
for more information.
Retrieve styled attribute information in this Context's theme. See
obtainStyledAttributes(AttributeSet, int[], int, int)
for more information.
Open a private file associated with this Context's application package for reading.
name | The name of the file to open; can not contain path separators. |
---|
FileNotFoundException |
---|
Open a private file associated with this Context's application package for writing. Creates the file if it doesn't already exist.
name | The name of the file to open; can not contain path separators. |
---|---|
mode | Operating mode. Use 0 or MODE_PRIVATE for the
default operation, MODE_APPEND to append to an existing file,
MODE_WORLD_READABLE and MODE_WORLD_WRITEABLE to control
permissions. |
FileNotFoundException |
---|
Open a new private SQLiteDatabase associated with this Context's application package. Create the database file if it doesn't exist.
name | The name (unique in the application package) of the database. |
---|---|
mode | Operating mode. Use 0 or MODE_PRIVATE for the
default operation, MODE_WORLD_READABLE
and MODE_WORLD_WRITEABLE to control permissions. |
factory | An optional factory class that is called to instantiate a cursor when query is called. |
SQLiteException | if the database file could not be opened. |
---|
Register to receive intent broadcasts, to run in the context of
scheduler. See
registerReceiver(BroadcastReceiver, IntentFilter)
for more
information. This allows you to enforce permissions on who can
broadcast intents to your receiver, or have the receiver run in
a different thread than the main application thread.
See BroadcastReceiver
for more information on Intent broadcasts.
receiver | The BroadcastReceiver to handle the broadcast. |
---|---|
filter | Selects the Intent broadcasts to be received. |
broadcastPermission | String naming a permissions that a broadcaster must hold in order to send an Intent to you. If null, no permission is required. |
scheduler | Handler identifying the thread that will receive the Intent. If null, the main thread of the process will be used. |
Register a BroadcastReceiver to be run in the main activity thread. The receiver will be called with any broadcast Intent that matches filter, in the main application thread.
The system may broadcast Intents that are "sticky" -- these stay around after the broadcast as finished, to be sent to any later registrations. If your IntentFilter matches one of these sticky Intents, that Intent will be returned by this function and sent to your receiver as if it had just been broadcast.
There may be multiple sticky Intents that match filter, in which case each of these will be sent to receiver. In this case, only one of these can be returned directly by the function; which of these that is returned is arbitrarily decided by the system.
If you know the Intent your are registering for is sticky, you can supply null for your receiver. In this case, no receiver is registered -- the function simply returns the sticky Intent that matches filter. In the case of multiple matches, the same rules as described above apply.
See BroadcastReceiver
for more information on Intent broadcasts.
Note: this method cannot be called from a
BroadcastReceiver
component; that is, from a BroadcastReceiver
that is declared in an application's manifest. It is okay, however, to call
this method from another BroadcastReceiver that has itself been registered
at run time with registerReceiver(BroadcastReceiver, IntentFilter)
, since the lifetime of such a
registered BroadcastReceiver is tied to the object that registered it.
receiver | The BroadcastReceiver to handle the broadcast. |
---|---|
filter | Selects the Intent broadcasts to be received. |
Remove the data previously sent with sendStickyBroadcast(Intent)
,
so that it is as if the sticky broadcast had never happened.
You must hold the BROADCAST_STICKY
permission in order to use this API. If you do not hold that
permission, SecurityException
will be thrown.
intent | The Intent that was previously broadcast. |
---|
Remove all permissions to access a particular content provider Uri
that were previously added with grantUriPermission(String, Uri, int)
. The given
Uri will match all previously granted Uris that are the same or a
sub-path of the given Uri. That is, revoking "content://foo/one" will
revoke both "content://foo/target" and "content://foo/target/sub", but not
"content://foo".
uri | The Uri you would like to revoke access to. |
---|---|
modeFlags | The desired access modes. Any combination of
Intent.FLAG_GRANT_READ_URI_PERMISSION or
Intent.FLAG_GRANT_WRITE_URI_PERMISSION . |
Broadcast the given intent to all interested BroadcastReceivers. This
call is asynchronous; it returns immediately, and you will continue
executing while the receivers are run. No results are propagated from
receivers and receivers can not abort the broadcast. If you want
to allow receivers to propagate results or abort the broadcast, you must
send an ordered broadcast using
sendOrderedBroadcast(Intent, String)
.
See BroadcastReceiver
for more information on Intent broadcasts.
intent | The Intent to broadcast; all receivers matching this Intent will receive the broadcast. |
---|
Broadcast the given intent to all interested BroadcastReceivers, allowing
an optional required permission to be enforced. This
call is asynchronous; it returns immediately, and you will continue
executing while the receivers are run. No results are propagated from
receivers and receivers can not abort the broadcast. If you want
to allow receivers to propagate results or abort the broadcast, you must
send an ordered broadcast using
sendOrderedBroadcast(Intent, String)
.
See BroadcastReceiver
for more information on Intent broadcasts.
intent | The Intent to broadcast; all receivers matching this Intent will receive the broadcast. |
---|---|
receiverPermission | (optional) String naming a permissions that a receiver must hold in order to receive your broadcast. If null, no permission is required. |
Version of sendBroadcast(Intent)
that allows you to
receive data back from the broadcast. This is accomplished by
supplying your own BroadcastReceiver when calling, which will be
treated as a final receiver at the end of the broadcast -- its
onReceive(Context, Intent)
method will be called with
the result values collected from the other receivers. The broadcast will
be serialized in the same way as calling
sendOrderedBroadcast(Intent, String)
.
Like sendBroadcast(Intent)
, this method is
asynchronous; it will return before
resultReceiver.onReceive() is called.
See BroadcastReceiver
for more information on Intent broadcasts.
intent | The Intent to broadcast; all receivers matching this Intent will receive the broadcast. |
---|---|
receiverPermission | String naming a permissions that a receiver must hold in order to receive your broadcast. If null, no permission is required. |
resultReceiver | Your own BroadcastReceiver to treat as the final receiver of the broadcast. |
scheduler | A custom Handler with which to schedule the resultReceiver callback; if null it will be scheduled in the Context's main thread. |
initialCode | An initial value for the result code. Often Activity.RESULT_OK. |
initialData | An initial value for the result data. Often null. |
initialExtras | An initial value for the result extras. Often null. |
Broadcast the given intent to all interested BroadcastReceivers, delivering them one at a time to allow more preferred receivers to consume the broadcast before it is delivered to less preferred receivers. This call is asynchronous; it returns immediately, and you will continue executing while the receivers are run.
See BroadcastReceiver
for more information on Intent broadcasts.
intent | The Intent to broadcast; all receivers matching this Intent will receive the broadcast. |
---|---|
receiverPermission | (optional) String naming a permissions that a receiver must hold in order to receive your broadcast. If null, no permission is required. |
Perform a sendBroadcast(Intent)
that is "sticky," meaning the
Intent you are sending stays around after the broadcast is complete,
so that others can quickly retrieve that data through the return
value of registerReceiver(BroadcastReceiver, IntentFilter)
. In
all other ways, this behaves the same as
sendBroadcast(Intent)
.
You must hold the BROADCAST_STICKY
permission in order to use this API. If you do not hold that
permission, SecurityException
will be thrown.
intent | The Intent to broadcast; all receivers matching this Intent will receive the broadcast, and the Intent will be held to be re-broadcast to future receivers. |
---|
Version of sendStickyBroadcast(Intent)
that allows you to
receive data back from the broadcast. This is accomplished by
supplying your own BroadcastReceiver when calling, which will be
treated as a final receiver at the end of the broadcast -- its
onReceive(Context, Intent)
method will be called with
the result values collected from the other receivers. The broadcast will
be serialized in the same way as calling
sendOrderedBroadcast(Intent, String)
.
Like sendBroadcast(Intent)
, this method is
asynchronous; it will return before
resultReceiver.onReceive() is called. Note that the sticky data
stored is only the data you initially supply to the broadcast, not
the result of any changes made by the receivers.
See BroadcastReceiver
for more information on Intent broadcasts.
intent | The Intent to broadcast; all receivers matching this Intent will receive the broadcast. |
---|---|
resultReceiver | Your own BroadcastReceiver to treat as the final receiver of the broadcast. |
scheduler | A custom Handler with which to schedule the resultReceiver callback; if null it will be scheduled in the Context's main thread. |
initialCode | An initial value for the result code. Often Activity.RESULT_OK. |
initialData | An initial value for the result data. Often null. |
initialExtras | An initial value for the result extras. Often null. |
Set the base theme for this context. Note that this should be called
before any views are instantiated in the Context (for example before
calling setContentView(View)
or
inflate(int, ViewGroup)
).
resid | The style resource describing the theme. |
---|
Launch a new activity. You will not receive any information about when the activity exits.
Note that if this method is being called from outside of an
Activity
Context, then the Intent must include
the FLAG_ACTIVITY_NEW_TASK
launch flag. This is because,
without being started from an existing Activity, there is no existing
task in which to place the new activity and thus it needs to be placed
in its own separate task.
This method throws ActivityNotFoundException
if there was no Activity found to run the given Intent.
intent | The description of the activity to start. |
---|
ActivityNotFoundException |
Start executing an Instrumentation
class. The given
Instrumentation component will be run by killing its target application
(if currently running), starting the target process, instantiating the
instrumentation component, and then letting it drive the application.
This function is not synchronous -- it returns as soon as the instrumentation has started and while it is running.
Instrumentation is normally only allowed to run against a package that is either unsigned or signed with a signature that the the instrumentation package is also signed with (ensuring the target trusts the instrumentation).
className | Name of the Instrumentation component to be run. |
---|---|
profileFile | Optional path to write profiling data as the instrumentation runs, or null for no profiling. |
arguments | Additional optional arguments to pass to the instrumentation, or null. |
Like startActivity(Intent)
, but taking a IntentSender
to start. If the IntentSender is for an activity, that activity will be started
as if you had called the regular startActivity(Intent)
here; otherwise, its associated action will be executed (such as
sending a broadcast) as if you had called
IntentSender.sendIntent
on it.
intent | The IntentSender to launch. |
---|---|
fillInIntent | If non-null, this will be provided as the
intent parameter to sendIntent(Context, int, Intent, IntentSender.OnFinished, Handler) . |
flagsMask | Intent flags in the original IntentSender that you would like to change. |
flagsValues | Desired values for any bits set in flagsMask |
extraFlags | Always set to 0. |
Request that a given application service be started. The Intent can either contain the complete class name of a specific service implementation to start, or an abstract definition through the action and other fields of the kind of service to start. If this service is not already running, it will be instantiated and started (creating a process for it if needed); if it is running then it remains running.
Every call to this method will result in a corresponding call to
the target service's onStart(Intent, int)
method,
with the intent given here. This provides a convenient way
to submit jobs to a service without having to bind and call on to its
interface.
Using startService() overrides the default service lifetime that is
managed by bindService(Intent, ServiceConnection, int)
: it requires the service to remain
running until stopService(Intent)
is called, regardless of whether
any clients are connected to it. Note that calls to startService()
are not nesting: no matter how many times you call startService(),
a single call to stopService(Intent)
will stop it.
The system attempts to keep running services around as much as possible. The only time they should be stopped is if the current foreground application is using so many resources that the service needs to be killed. If any errors happen in the service's process, it will automatically be restarted.
This function will throw SecurityException
if you do not
have permission to start the given service.
service | Identifies the service to be started. The Intent may
specify either an explicit component name to start, or a logical
description (action, category, etc) to match an
IntentFilter published by a service. Additional values
may be included in the Intent extras to supply arguments along with
this specific start call. |
---|
ComponentName
of the actual service that was started is
returned; else if the service does not exist null is returned.SecurityException |
Request that a given application service be stopped. If the service is not running, nothing happens. Otherwise it is stopped. Note that calls to startService() are not counted -- this stops the service no matter how many times it was started.
Note that if a stopped service still has ServiceConnection
objects bound to it with the BIND_AUTO_CREATE
set, it will
not be destroyed until all of these bindings are removed. See
the Service
documentation for more details on a
service's lifecycle.
This function will throw SecurityException
if you do not
have permission to stop the given service.
service | Description of the service to be stopped. The Intent may
specify either an explicit component name to start, or a logical
description (action, category, etc) to match an
IntentFilter published by a service. |
---|
SecurityException |
Disconnect from an application service. You will no longer receive calls as the service is restarted, and the service is now allowed to stop at any time.
conn | The connection interface previously supplied to bindService(). |
---|
Unregister a previously registered BroadcastReceiver. All filters that have been registered for this BroadcastReceiver will be removed.
receiver | The BroadcastReceiver to unregister. |
---|