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Location:
e32property.h
Link against: euser.lib
class RProperty : public RHandleBase;
User side interface to Publish & Subscribe.
The class defines a handle to a property, a single data value representing an item of state information. Threads can publish (change) a property value through this handle. Threads can also subscribe (request notification of changes) to a property value through this handle; they can also retrieve the current property value.
RHandleBase - A handle to an object
RProperty -
Defined in RProperty:
Attach(), Cancel(), Define(), Delete(), Delete(), EByteArray, EInt, ELargeByteArray, ELargeText, EText, ETypeLimit, ETypeMask, Get(), Get(), Get(), Get(), Get(), Get(), KMaxLargePropertySize, KMaxPropertySize, Set(), Set(), Set(), Set(), Set(), Set(), Subscribe(), TType, anonymous, anonymous
Inherited from RHandleBase:
Attributes(),
Close(),
Duplicate(),
FullName(),
Handle(),
HandleInfo(),
Name(),
Open(),
SetHandle(),
SetHandleNC(),
SetReturnedHandle(),
iHandle
| Capability: | WriteDeviceData | if aCategory==KUidSystemCategoryValue. WriteDeviceData if aCategory not equal to the current process's Secure ID and aCategory<KUidSecurityThresholdCategoryValue. |
static IMPORT_C TInt Define(TUid aCategory, TUint aKey, TInt aAttr, TInt aPreallocate=0);
Defines a property.
Defines the attributes and access control for a property. This can only be done once for each property. Subsequent attempts to define the same property will return KErrAlreadyExists.
Only processes with the write-system-data capability are allowed to define properties in the system category (KUidSystemCategory). Any attempt to define a property in the system category by a process with insufficient capabilities will fail with a KErrPermissionDenied error.
Following definition, the property has a default value, 0 for integer properties and zero-length data for byte-array and text properties. Pending subscriptions for this property will not be completed until a new value is published.
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static IMPORT_C TInt Delete(TUid aCategory, TUint aKey);
Deletes a property.
This can only be called by the property owner, as defined by the process Security ID; any attempt by another process to delete the property will fail.
Any pending subscriptions for this property will be completed with KErrNotFound. Any new request will not complete until the property is defined and published again.
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static IMPORT_C TInt Delete(TUint aKey);
Deletes a property.
The category ID for the property will be the same as the current processes Secure ID.
Any pending subscriptions for this property will be completed with KErrNotFound. Any new request will not complete until the property is defined and published again.
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static IMPORT_C TInt Get(TUid aCategory, TUint aKey, TInt &aValue);
Gets an integer property.
The function gets the integer value of the specified property.
The Platform Security attributes of the current process are checked against the Read Policy which was specified when the property was defined. If this check fails the action taken is determined by the system wide Platform Security configuration. If PlatSecDiagnostics is ON, then a diagnostic message is emitted. If PlatSecEnforcement is OFF, then this function will return KErrNone even though the check failed.
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static IMPORT_C TInt Get(TUid aCategory, TUint aKey, TDes8 &aValue);
Gets a binary property.
The function gets the byte-array (binary) value of the specified property.
The Platform Security attributes of the current process are checked against the Read Policy which was specified when the property was defined. If this check fails the action taken is determined by the system wide Platform Security configuration. If PlatSecDiagnostics is ON, then a diagnostic message is emitted. If PlatSecEnforcement is OFF, then this function will return KErrNone even though the check failed.
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static IMPORT_C TInt Get(TUid aCategory, TUint aKey, TDes16 &aValue);
Gets a text property.
The function gets the text value of the specified property.
The Platform Security attributes of the current process are checked against the Read Policy which was specified when the property was defined. If this check fails the action taken is determined by the system wide Platform Security configuration. If PlatSecDiagnostics is ON, then a diagnostic message is emitted. If PlatSecEnforcement is OFF, then this function will return KErrNone even though the check failed.
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static IMPORT_C TInt Set(TUid aCategory, TUint aKey, TInt aValue);
Sets an integer property.
The function publishes a new integral property value.
Any pending subscriptions for this property will be completed.
The Platform Security attributes of the current process are checked against the Write Policy which was specified when the property was defined. If this check fails the action taken is determined by the system wide Platform Security configuration. If PlatSecDiagnostics is ON, then a diagnostic message is emitted. If PlatSecEnforcement is OFF, then this function will return KErrNone even though the check failed.
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static IMPORT_C TInt Set(TUid aCategory, TUint aKey, const TDesC8 &aValue);
Sets a binary property.
The function Publishes a new byte-array (binary) value for the specified property.
Any pending subscriptions for this property will be completed.
Note that if the new property value requires more storage space than is currently allocated, then memory allocation will be required. This invalidates any real-time guarantee, i.e. the guarantee that the operation will complete within a bounded time.
The Platform Security attributes of the current process are checked against the Write Policy which was specified when the property was defined. If this check fails the action taken is determined by the system wide Platform Security configuration. If PlatSecDiagnostics is ON, then a diagnostic message is emitted. If PlatSecEnforcement is OFF, then this function will return KErrNone even though the check failed.
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static IMPORT_C TInt Set(TUid aCategory, TUint aKey, const TDesC16 &aValue);
Sets a text property.
The function publishes a new text value for the specified property.
Any pending subscriptions for this property will be completed.
Note that if the new property value requires more storage space than is currently allocated, then memory allocation will be required. This invalidates any real-time guarantee, i.e. the guarantee that the operation will complete within a bounded time.
The Platform Security attributes of the current process are checked against the Write Policy which was specified when the property was defined. If this check fails the action taken is determined by the system wide Platform Security configuration. If PlatSecDiagnostics is ON, then a diagnostic message is emitted. If PlatSecEnforcement is OFF, then this function will return KErrNone even though the check failed.
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IMPORT_C TInt Attach(TUid aCategory, TUint aKey, TOwnerType aType=EOwnerProcess);
Attaches to the specified property.
The function creates a handle (this object) to the specified property. This allows the caller to subscribe for notification of changes to this property, and to faster and real-time property access methods.
If the specified property does not exist, then this operation will still succeed. However, memory allocation will be required. Note that this invalidates any real-time guarantee, i.e. the guarantee that the operation completes within a bounded time.
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IMPORT_C void Subscribe(TRequestStatus &aRequest);
Subscribes to a property.
The function issues an asynchronous request to be notified when the property is changed. The calling thread is signalled, and the specified request status object is updated when the property is next changed.
The property may change several times before the subscribing thread can deal with a notification request completion. To ensure that the subscriber does not miss updates, it should re-issue a subscription request before retrieving the current value and acting on it.
If the property has not been defined, the request does not complete until the property is subsequently defined and published. When defined, if the caller process doesn't pass the Read Policy, then the request completes with KErrPermissionDenied.
If the property is already defined, and the caller process doesn't pass the Read Policy, then the request completes immediately with KErrPermissionDenied.
When Read Policy checks fail the action taken is determined by the system wide Platform Security configuration. If PlatSecDiagnostics is ON, then a diagnostic message is emitted. If PlatSecEnforcement is OFF, then the request will complete successfully even though the check failed.
If an outstanding request is cancelled through a call to Cancel(), then it completes with KErrCancel.
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IMPORT_C void Cancel();
Cancels an outstanding subscription request for this property handle.
If the request has not already completed, then it completes with KErrCancel.
IMPORT_C TInt Get(TInt &aValue);
Gets the integer value of this property.
The implementation guarantees that this call has a bounded response time.
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IMPORT_C TInt Get(TDes8 &aValue);
Gets the byte-array (binary) value of this property.
The implementation guarantees that this call has a bounded response time.
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IMPORT_C TInt Get(TDes16 &aValue);
Gets the text value of this property.
The implementation guarantees that this call has a bounded response time.
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IMPORT_C TInt Set(TInt aValue);
Sets a new integer value for this property.
The function publishes the attached new integral property value, and any pending subscriptions for this property are completed.
The implementation guarantees that this call has a bounded response time.
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IMPORT_C TInt Set(const TDesC8 &aValue);
Sets the byte-array (binary) property.
The function publishes the attached new binary property value, and any pending subscriptions for this property are completed.
The implementation guarantees that this call has a bounded response time only if the new property value requires no more storage space than is currently allocated. If more memory needs to be allocated, then this invalidates the real-time guarantee.
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IMPORT_C TInt Set(const TDesC16 &aValue);
Sets the text property
The function publishes the attached new text property value, and any pending subscriptions for this property are completed.
The implementation guarantees that this call has a bounded response time only if the new property value requires no more storage space than is currently allocated. If more memory needs to be allocated, then this invalidates the real-time guarantee.
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n/a
The largest supported property value, in bytes, for byte-array (binary) types and text types.
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n/a
The largest supported property value, in bytes, for large byte-array (binary) types and large text types.
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TType
Property type attribute.
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Copyright ©2008 Symbian Software Ltd. |
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