/// <summary>
/// Returns the set of candidates that may satisfy this navigation request.
/// </summary>
/// <param name="region">The region containing items that may satisfy the navigation request.</param>
/// <param name="candidateNavigationContract">The candidate navigation target as determined by <see cref="GetContractFromNavigationContext"/></param>
/// <returns>An enumerable of candidate objects from the <see cref="IRegion"/></returns>
protected virtual IEnumerable <VisualElement> GetCandidatesFromRegion(IRegion region, string candidateNavigationContract)
{
if (region is null)
{
throw new ArgumentNullException(nameof(region));
}
if (string.IsNullOrEmpty(candidateNavigationContract))
{
throw new ArgumentNullException(nameof(candidateNavigationContract));
}
var contractCandidates = GetCandidatesFromRegionViews(region, candidateNavigationContract);
if (!contractCandidates.Any())
{
var matchingType = _container.GetRegistrationType(candidateNavigationContract);
if (matchingType is null)
{
return(Array.Empty <VisualElement>());
}
return(GetCandidatesFromRegionViews(region, matchingType.FullName));
}
return(contractCandidates);
}
