Lots of work on focus management

Source/Integration/InputModeRequest.cpp

@@ -0,0 +1,97 @@
+////////////////////////////////////////////////////////////
+//
+// InputModeRequest.cpp
+//
+////////////////////////////////////////////////////////////
+
+#include "InputModeRequest.h"
+#include "Common.h"
+
+bool FlxInputModeRequest::operator==(const FlxInputModeRequest &Other) const
+{
+	return (Widget == Other.Widget) &&
+		(Focus == Other.Focus) &&
+		(ShowPointer == Other.ShowPointer) &&
+		(BlockInput == Other.BlockInput) &&
+		(EnableInputComponent == Other.EnableInputComponent);
+}
+
+bool FlxInputModeRequests::SanityCheck(const FlxInputModeRequest &Request)
+{
+	if (Request.Widget == nullptr)
+	{
+		UE_LOG(LogLuprexIntegration, Error, TEXT("RequestEvents called with null widget."));
+		return false;
+	}
+	return true;
+}
+
+void FlxInputModeRequests::SplitHighLow(View &High, View &Low)
+{
+	int32 NumHigh = 0;
+	while ((NumHigh < Requests.Num()) && (Requests[NumHigh].IsHighPrio())) NumHigh++;
+	int32 NumLow = Requests.Num() - NumHigh;
+	High = View(Requests.GetData(), NumHigh);
+	Low = View(Requests.GetData() + NumHigh, NumLow);
+}
+
+void FlxInputModeRequests::Request(const FlxInputModeRequest &NewRequest)
+{
+	bool IsHigh = NewRequest.IsHighPrio();
+
+	// Divide the array into a high-priority slice and a low-priority slice.
+	View High, Low;
+	SplitHighLow(High, Low);
+
+	// Stamp this request with a fresh sequence number.
+	FlxInputModeRequest Stamped = NewRequest;
+	Stamped.SequenceNumber = ++NextSequenceNumber;
+
+	// We're going to build a new version of the requests array.
+	TArray<FlxInputModeRequest> Updated;
+
+	// Add all high priority requests to the updated array, new request first.
+	if (IsHigh) Updated.Add(Stamped);
+	for (const FlxInputModeRequest &Req : High)
+		if (Req.Widget != NewRequest.Widget) Updated.Add(Req);
+
+	// Add all low priority requests to the updated array, new request first.
+	if (!IsHigh) Updated.Add(Stamped);
+	for (const FlxInputModeRequest &Req : Low)
+		if (Req.Widget != NewRequest.Widget) Updated.Add(Req);
+
+	Swap(Requests, Updated);
+}
+
+void FlxInputModeRequests::SetEnableInputComponent(UUserWidget *Widget, bool EnableInputComponent)
+{
+	for (FlxInputModeRequest &Req : Requests)
+	{
+		if (Req.Widget == Widget)
+		{
+			Req.EnableInputComponent = EnableInputComponent;
+			return;
+		}
+	}
+	FlxInputModeRequest NewReq;
+	NewReq.Widget = Widget;
+	NewReq.EnableInputComponent = EnableInputComponent;
+	Request(NewReq);
+}
+
+void FlxInputModeRequests::Remove(UUserWidget *Widget)
+{
+	Requests.RemoveAll([Widget](const FlxInputModeRequest &Entry)
+	{
+		return Entry.Widget == Widget;
+	});
+}
+
+void FlxInputModeRequests::GarbageCollect()
+{
+	Requests.RemoveAll([](const FlxInputModeRequest &Entry)
+	{
+		return !IsValid(Entry.Widget);
+	});
+}
+