| class MAknsDataContext |
Interface that provides context sensitive control over data allocation. MAknsDataContext can be used to indicate need for specific skin items and thus to ensure that they are allocated before first use.
This is a public class with exported functions. The class is not usually intended for user derivation - concrete classes implementing the interface are provided by the library. See AknsUtils::CreateDataContextForContainerL() for further details.
AknSkins.lib
2.0
| Public Member Functions | |
|---|---|
| ~MAknsDataContext() | |
| void | ReleaseItem(const TAknsItemID &) |
| void | ReserveItemL(const TAknsItemID &) |
| IMPORT_C TTypeUid::Ptr | SupplyMopObject(TTypeUid, MAknsDataContext *) |
| Protected Member Functions | |
|---|---|
| TInt | Reserved1() |
| TInt | Reserved2() |
| ~MAknsDataContext | ( | ) | [inline, virtual] |
Destructor. Destructor is only provided to enable deletion using base class pointer. Caller should never delete context retrieved using MObjectProvider interface.
| void | ReleaseItem | ( | const TAknsItemID & | aID | ) | [pure virtual] |
Indicates that specified item will no longer be used. Instructs the data context that the specified item will not be used by caller anymore. Exact behavior (e.g. whether cached instance is deallocated) depends on the cache policy of data context and skin instance. Controls should not usually call this method, but instead allow data context (in most cases implemented by a container) go out of scope.
2.0
| const TAknsItemID & aID | Item ID of the item to be released. |
| void | ReserveItemL | ( | const TAknsItemID & | aID | ) | [pure virtual] |
Reserves and allocates specified item. Instructs the data context that the specified item will be used by caller and should be allocated and cached by skin instance. Any control using cached skin items should reserve them, preferably in ConstructL(), by calling this method. Note that reservation does not guarantee that the item will be available in cache - it's only a tentative request for allocation.
2.0
Exceptions:
If item data allocation fails, function leaves with error code.
| const TAknsItemID & aID | Item ID of the item to be reserved. |
| IMPORT_C TTypeUid::Ptr | SupplyMopObject | ( | TTypeUid | aId, |
| MAknsDataContext * | aContext | |||
| ) | [static] | |||
Returns type UID pointer that can be used in MopSupplyObject.
2.0
Type UID pointer containing aContext, or NULL type UID pointer if given type UID does not match MAknsDataContext or aContext is NULL.
| TTypeUid aId | Type UID, should be the same that was given as aId parameter of MopSupplyObject. |
| MAknsDataContext * aContext | Pointer to an MAknsDataContext instance. |