/// <summary>
/// Creates a view model.
/// </summary>
/// <param name="vmId">Identifies the view model.</param>
/// <param name="vmArg">Optional view model's initialization argument.</param>
/// <param name="vmNamespace">Optional view model type's namespace.</param>
/// <returns>View model instance.</returns>
protected virtual BaseVM CreateVM(string vmId, object vmArg = null, string vmNamespace = null)
{
// If the namespace argument is given, try to resolve the view model type to that namespace.
vmNamespace = vmNamespace ?? ExtractNamespace(ref vmArg);
// If the view model Id is in the form of a delimited path, it has a master view model.
BaseVM masterVM = null;
var path = vmId.Split('.');
if (path.Length > 1)
{
// Get the master view model; create the instance if it doesn't exist.
var masterVMId = vmId.Remove(vmId.LastIndexOf('.'));
lock (_activeVMs)
{
if (!_activeVMs.ContainsKey(masterVMId))
{
masterVM = CreateVM(masterVMId, null, vmNamespace);
_activeVMs.TryAdd(masterVMId, new VMInfo {
Instance = masterVM
});
}
else
{
masterVM = _activeVMs[masterVMId].Instance;
}
}
vmId = vmId.Remove(0, vmId.LastIndexOf('.') + 1);
}
// If the view model Id contains instance Id, parse it out.
string vmTypeName = vmId;
string vmInstanceId = null;
if (vmTypeName.Contains('$'))
{
path = vmTypeName.Split('$');
vmTypeName = path[0];
vmInstanceId = path[1];
}
// Get the view model instance from the master view model, and if not, create it ourselves here.
var vmInstance = masterVM?.GetSubVM(vmTypeName, vmInstanceId)
?? _vmFactory.GetInstance(vmTypeName, vmInstanceId, vmNamespace)
?? throw new Exception($"[dotNetify] ERROR: '{vmId}' is not a known view model! Its assembly must be registered through VMController.RegisterAssembly.");
// If there are view model arguments, set them into the instance.
if (vmArg is JObject)
{
foreach (var prop in (vmArg as JObject).Properties())
{
UpdateVM(vmInstance, prop.Name, prop.Value.ToString());
}
}
// Pass the view model instance to the master view model.
masterVM?.OnSubVMCreated(vmInstance);
return(vmInstance);
}
/// <summary>
/// Creates a view model.
/// </summary>
/// <param name="vmId">Identifies the view model.</param>
/// <param name="vmArg">Optional view model's initialization argument.</param>
/// <param name="vmNamespace">Optional view model type's namespace.</param>
/// <returns>View model instance.</returns>
protected virtual BaseVM CreateVM(string vmId, object vmArg = null, string vmNamespace = null)
{
// If the namespace argument is given, try to resolve the view model type to that namespace.
vmNamespace = vmNamespace ?? ExtractNamespace(ref vmArg);
// If the view model Id is in the form of a delimited path, it has a master view model.
BaseVM masterVM = null;
var path = vmId.Split('.');
if (path.Length > 1)
{
// Get the master view model; create the instance if it doesn't exist.
var masterVMId = vmId.Remove(vmId.LastIndexOf('.'));
lock (_activeVMs)
{
if (!_activeVMs.ContainsKey(masterVMId))
{
masterVM = CreateVM(masterVMId, null, vmNamespace);
_activeVMs.TryAdd(masterVMId, new VMInfo {
Instance = masterVM
});
}
else
{
masterVM = _activeVMs[masterVMId].Instance;
}
}
vmId = vmId.Remove(0, vmId.LastIndexOf('.') + 1);
}
// If the view model Id contains instance Id, parse it out.
string vmTypeName = vmId;
string vmInstanceId = null;
if (vmTypeName.Contains('$'))
{
path = vmTypeName.Split('$');
vmTypeName = path[0];
vmInstanceId = path[1];
}
// Get the view model instance from the master view model.
var vmInstance = masterVM?.GetSubVM(vmTypeName, vmInstanceId);
// If still no view model instance, create it ourselves here.
if (vmInstance == null)
{
Type vmType = null;
if (vmNamespace != null)
{
vmType = _vmTypes.FirstOrDefault(i => i.FullName == $"{vmNamespace}.{vmTypeName}");
}
vmType = vmType ?? _vmTypes.FirstOrDefault(i => i.Name == vmTypeName);
if (vmType == null)
{
throw new Exception($"[dotNetify] ERROR: '{vmId}' is not a known view model! Its assembly must be registered through VMController.RegisterAssembly.");
}
try
{
if (vmInstanceId != null)
{
vmInstance = CreateInstance(vmType, new object[] { vmInstanceId }) as BaseVM;
}
}
catch (MissingMethodException)
{
Trace.Fail($"[dotNetify] ERROR: '{vmTypeName}' has no constructor accepting instance ID.");
}
try
{
if (vmInstance == null)
{
vmInstance = CreateInstance(vmType, null) as BaseVM;
}
}
catch (MissingMethodException)
{
Trace.Fail($"[dotNetify] ERROR: '{vmTypeName}' has no parameterless constructor.");
}
}
// If there are view model arguments, set them into the instance.
if (vmArg is JObject)
{
foreach (var prop in (vmArg as JObject).Properties())
{
UpdateVM(vmInstance, prop.Name, prop.Value.ToString());
}
}
// Pass the view model instance to the master view model.
masterVM?.OnSubVMCreated(vmInstance);
return(vmInstance);
}
