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ISideShowCapabilitiesCollection::GetAt Method 

Enables the gadget to retrieve the ISideShowCapabilities interface at a specified index.

Declaration

[C++]

HRESULT GetAt(
    [in]  DWORD in_pdwIndex,
    [out] ISideShowCapabilities ** out_ppDevice
);

Parameters

in_ pdwIndex

[in] A DWORD value that specifies the index of the device for which the ISideShowCapabilities objects are to be retrieved. The index is zero-based and sequential.

out_ppDevice

[out] A pointer to an interface pointer to the ISideShowCapabilities interface of the specified device.

Return Values

Possible values include, but are not limited to, those in the following table.

HRESULT value

Description

S_OK

Success, indicating that the requested capabilities have been returned.

E_INVALIDARG

The index passed in is invalid.

Remarks

You must call Release on the ISideShowCapabilities interface that is returned by this method.

Example

This example demonstrates how to retrieve the ISideShowCapabilities interface for each associated device.

[C++]

HRESULT hr;
ISideShowCapabilitiesCollection* pICapabilitiesCollection = NULL;

//
// Call GetDeviceCapabilities using the previously established pointer
// to the ContentManager object and check for failures.
// If successful, this call will return a pointer
// to an ISideShowCapabilitiesCollection interface.
//
hr = pISideShowContentManager->GetDeviceCapabilities(&pICapabilitiesCollection);
if (SUCCEEDED(hr) && NULL != pICapabilitiesCollection)
{
    DWORD NumDevices = 0;
    ISideShowCapabilities* pIDeviceCapabilities = NULL;
    
    hr = pICapabilitiesCollection->GetCount(&NumDevices);
    if (SUCCEEDED(hr) && NumDevices != 0)
    {
        for (DWORD Index = 0; Index < NumDevices; ++Index)
        {
            hr = pICapabilitiesCollection->GetAt(Index, &pIDeviceCapabilities);
            if (SUCCEEDED(hr) && NULL != pIDeviceCapabilities)
            {
                WCHAR DeviceIdentifier[MAX_PATH];
                unsigned short ScreenWidth;
                unsigned short ScreenHeight;

                //
                // Call a routine that will retrieve several individual
                // device capabilities. This routine will call
                // GetCapability once for each of the capabilities it
                // is meant to retrieve.
                //
                GetDeviceCapabilities(pIDeviceCapabilities, 
                                      DeviceIdentifier,
                                      MAX_PATH,
                                      &ScreenHeight, 
                                      &ScreenWidth);

                //
                // Call an application-specific routine to do something
                // with the retrieved capabilities.
                //
                StoreDeviceCapabilities(DeviceIdentifier,
                                        ScreenHeight, 
                                        ScreenWidth);

                //
                // Release the ISideShowCapabilities interface pointer.
                //
                pIDeviceCapabilities->Release();
                pIDeviceCapabilities = NULL;
            }
        }
    }

    //
    // Release the ISideShowCapabilitiesCollection interface pointer.
    //
    pICapabilitiesCollection->Release();
    pICapabilitiesCollection = NULL;
}
else
{
    //
    // Handling of failures will be application-specific.
    //
    HandleFailure("GetDeviceCapabilities", hr);
}

Applies To

ISideShowCapabilitiesCollection