async Task InitializeExtensionChain()
{
// Create an initial empty extension chain. This avoid crashes in case a call to SupportsObject ends
// calling methods from the extension
var tempExtensions = new List <DocumentControllerExtension> {
new DefaultControllerExtension()
};
extensionChain = ExtensionChain.Create(tempExtensions.ToArray());
foreach (var e in tempExtensions)
{
await e.Init(this, null);
}
// Collect extensions that support this object
var documentControllerService = await Runtime.GetService <DocumentControllerService> ();
var extensions = new List <DocumentControllerExtension> ();
foreach (var node in documentControllerService.GetModelExtensions(extensionContext))
{
if (node.Data.CanHandle(this))
{
var ext = node.CreateInstance();
if (!(ext is DocumentControllerExtension controllerExtension))
{
throw new InvalidOperationException("Invalid document controller extension type: " + ext.GetType());
}
if (await controllerExtension.SupportsController(this))
{
controllerExtension.SourceExtensionNode = node;
extensions.Add(controllerExtension);
}
else
{
controllerExtension.Dispose();
}
}
}
extensionChain.Dispose();
// Now create the final extension chain
extensions.Reverse();
var defaultExts = new List <DocumentControllerExtension> {
new DefaultControllerExtension()
};
defaultExts.Reverse();
extensions.AddRange(defaultExts);
extensionChain = ExtensionChain.Create(extensions.ToArray());
extensionChain.SetDefaultInsertionPosition(defaultExts.FirstOrDefault());
foreach (var e in extensions)
{
await e.Init(this, GetExtensionStatus (e));
}
itemExtension = extensionChain.GetExtension <DocumentControllerExtension> ();
foreach (var e in extensions)
{
e.OnExtensionChainCreated();
}
OnExtensionChainCreated();
if (extensions.Count - defaultExts.Count > 0)
{
NotifyContentChanged();
}
}
Properties GetExtensionStatus(DocumentControllerExtension ext)
{
return(lastKnownStatus?.Get <Properties> (ExtensionPropertyPrefix + ext.Id));
}
void StoreExtensionStatus(DocumentControllerExtension ext)
{
var s = ext.GetDocumentStatus();
lastKnownStatus.Set(ExtensionPropertyPrefix + ext.Id, s);
}
protected override void InitializeChain(ChainedExtension next)
{
base.InitializeChain(next);
this.next = FindNextImplementation <DocumentControllerExtension> (next);
}