private async Task <T> GetServiceAsync <T>(IAsyncServiceProvider asyncServiceProvider, Type serviceType) where T : class
{
T result = null;
await ThreadHelper.JoinableTaskFactory.RunAsync(async() =>
{
Guid serviceTypeGuid = serviceType.GUID;
object serviceInstance = await asyncServiceProvider.QueryServiceAsync(ref serviceTypeGuid);
await ThreadHelper.JoinableTaskFactory.SwitchToMainThreadAsync();
result = serviceInstance as T ?? GetService(serviceType) as T;
});
return(result);
}
/// <summary>
/// Helper method to use async/await with IAsyncServiceProvider implementation
/// </summary>
/// <param name="asyncServiceProvider">IAsyncServciceProvider instance</param>
/// <param name="serviceType">Type of the Visual Studio service requested</param>
/// <returns>Service object as type of T</returns>
public static async Task <T> GetServiceAsync <T>(this IAsyncServiceProvider asyncServiceProvider, Type serviceType) where T : class
{
T returnValue = null;
await ThreadHelper.JoinableTaskFactory.RunAsync(async() =>
{
object serviceInstance = null;
Guid serviceTypeGuid = serviceType.GUID;
serviceInstance = await asyncServiceProvider.QueryServiceAsync(ref serviceTypeGuid);
// We have to make sure we are on main UI thread before trying to cast as underlying implementation
// can be an STA COM object and doing a cast would require calling QueryInterface/AddRef marshaling
// to main thread via COM.
await ThreadHelper.JoinableTaskFactory.SwitchToMainThreadAsync();
returnValue = serviceInstance as T;
});
return(returnValue);
}