XRPtr<Interface> (Windows Embedded CE 6.0)
1/6/2010
An XRPtr<Interface> object encapsulates a COM interface pointer to a Silverlight object and is called a "smart pointer." This template class manages reference count and lifetime ownership for object pointers through calls to the IUnknown member functions QueryInterface, AddRef, and Release.
Syntax
template<typename Interface> class XRPtr
Methods
| Method | Description |
|---|---|
Calls the AddRef method of IUnknown on the encapsulated interface pointer. |
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Encapsulates a raw interface pointer in this smart pointer's type. |
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Extracts and returns the encapsulated interface pointer, and relinquishes ownership so that the returned interface will not be released by this smart pointer. |
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Calls the Release method of IUnknown on the encapsulated interface pointer. |
Operators
| Operator | Description |
|---|---|
Assigns a new value to an existing XRPtr<Interface> object. |
|
Returns the address of the interface pointer contained in this class. |
|
Either sets the interface pointer, copies the interface pointer and increments the reference count, or allows for the assignment of NULL to the class. |
Remarks
Smart pointers manage the reference count of an object. A smart pointer will automatically call IUnknown::Release when the smart pointer goes out of scope.
We recommend that you use smart pointers when you call methods that pass IXRDependencyObject-derived objects in Silverlight for Windows Embedded, instead of explicitly calling IUnknown::QueryInterface to convert a generic interface into the required object type.
All objects in Silverlight for Windows Embedded have smart pointer aliases declared for them. For example, to create a smart pointer instead of a raw interface pointer to IXRButton, you can create a smart pointer of type IXRButtonPtr. You can also create a smart pointer by using the template class type XRPtr<XRButton>.
The following example code creates a smart pointer by using a smart pointer alias:
IXRButtonPtr pButton;
pApplication->CreateObject(&pButton);
The following example code creates a smart pointer by using the template class:
XRPtr<XRButton> pButton;
pApplication->CreateObject(&pButton);
Requirements
| Header | XRPtr.h |
| sysgen | SYSGEN_XAML_RUNTIME |
| Windows Embedded CE | Windows Embedded CE 6.0 R3 |
See Also
Reference
Classes for Application Management