Replaced in ImGui Input Handler hard-coded assumptions about console open and stop play session shortcuts with values taken from input settings and input binding manager. Testing functions are available for inheriting classes.

Source/ImGui/ImGui.Build.cs

@@ -65,6 +65,7 @@ public class ImGui : ModuleRules
 				new string[]
 				{
 					"Settings",
+					"UnrealEd",
 				}
 				);
 		}

Source/ImGui/Private/ImGuiInputHandler.cpp

@@ -10,24 +10,64 @@
 #include <Engine/Console.h>
 #include <Input/Events.h>
 
+#if WITH_EDITOR
+#include <Commands/InputBindingManager.h>
+#include <Commands/InputChord.h>
+#include <DebuggerCommands.h>
+
+// Version 4.18 added support for dual key bindings.
+#include <Runtime/Launch/Resources/Version.h>
+#define WITH_SINGLE_KEY_BINDING		(ENGINE_MAJOR_VERSION < 4 || (ENGINE_MAJOR_VERSION == 4 && ENGINE_MINOR_VERSION < 18))
+#endif // WITH_EDITOR
+
+
+DEFINE_LOG_CATEGORY_STATIC(LogImGuiInputHandler, Warning, All);
 
 FImGuiInputResponse UImGuiInputHandler::OnKeyDown(const FKeyEvent& KeyEvent)
 {
-	// Ignore console open events, so we don't block it from opening.
+	// Ignore console events, so we don't block it from opening.
-	if (KeyEvent.GetKey() == EKeys::Tilde)
+	if (IsConsoleEvent(KeyEvent))
 	{
 		return FImGuiInputResponse{ false, false };
 	}
 
-	// Ignore escape event, if they are not meant for ImGui control.
+#if WITH_EDITOR
-	if (KeyEvent.GetKey() == EKeys::Escape && !HasImGuiActiveItem())
+	// If there is no active ImGui control that would get precedence and this key event is bound to a stop play session
+	// command, then ignore that event and let the command execute.
+	if (!HasImGuiActiveItem() && IsStopPlaySessionEvent(KeyEvent))
 	{
 		return FImGuiInputResponse{ false, false };
 	}
+#endif // WITH_EDITOR
 
 	return DefaultResponse();
 }
 
+bool UImGuiInputHandler::IsConsoleEvent(const FKeyEvent& KeyEvent) const
+{
+	// Checking modifiers is based on console implementation.
+	const bool bModifierDown = KeyEvent.IsControlDown() || KeyEvent.IsShiftDown() || KeyEvent.IsAltDown() || KeyEvent.IsCommandDown();
+	return !bModifierDown && GetDefault<UInputSettings>()->ConsoleKeys.Contains(KeyEvent.GetKey());
+}
+
+#if WITH_EDITOR
+bool UImGuiInputHandler::IsStopPlaySessionEvent(const FKeyEvent& KeyEvent) const
+{
+	if (StopPlaySessionCommandInfo.IsValid())
+	{
+		const FInputChord InputChord(KeyEvent.GetKey(), KeyEvent.IsShiftDown(), KeyEvent.IsControlDown(), KeyEvent.IsAltDown(), KeyEvent.IsCommandDown());
+#if WITH_SINGLE_KEY_BINDING
+		const bool bHasActiveChord = (InputChord == StopPlaySessionCommandInfo->GetActiveChord().Get());
+#else
+		const bool bHasActiveChord = StopPlaySessionCommandInfo->HasActiveChord(InputChord);
+#endif
+		return bHasActiveChord && FPlayWorldCommands::GlobalPlayWorldActions->CanExecuteAction(StopPlaySessionCommandInfo.ToSharedRef());
+	}
+
+	return false;
+}
+#endif // WITH_EDITOR
+
 bool UImGuiInputHandler::HasImGuiActiveItem() const
 {
 	FImGuiContextProxy* ContextProxy = ModuleManager->GetContextManager().GetContextProxy(ContextIndex);
@@ -39,4 +79,13 @@ void UImGuiInputHandler::Initialize(FImGuiModuleManager* InModuleManager, UGameV
 	ModuleManager = InModuleManager;
 	GameViewport = InGameViewport;
 	ContextIndex = InContextIndex;
+
+#if WITH_EDITOR
+	StopPlaySessionCommandInfo = FInputBindingManager::Get().FindCommandInContext("PlayWorld", "StopPlaySession");
+	if (!StopPlaySessionCommandInfo.IsValid())
+	{
+		UE_LOG(LogImGuiInputHandler, Warning, TEXT("Couldn't find 'StopPlaySession' in context 'PlayWorld'. ")
+			TEXT("PIE feature allowing execution of stop command in ImGui input mode will be disabled."));
+	}
+#endif // WITH_EDITOR
 }

Source/ImGui/Public/ImGuiInputHandler.h

@@ -15,6 +15,11 @@ struct FAnalogInputEvent;
 struct FCharacterEvent;
 struct FKeyEvent;
 
+#if WITH_EDITOR
+class FUICommandInfo;
+#endif // WITH_EDITOR
+
+
 /** Response used by ImGui Input Handler to communicate input handling requests. */
 struct IMGUI_API FImGuiInputResponse
 {
@@ -149,7 +154,29 @@ public:
 
 protected:
 
-	/** Checks whether corresponding ImGui context has an active item. */
+	/**
+	 * Checks whether this is a key event that can open console.
+	 *
+	 * @param KeyEvent - Key event to test.
+	 * @returns True, if this key event can open console. 
+	 */
+	bool IsConsoleEvent(const FKeyEvent& KeyEvent) const;
+
+#if WITH_EDITOR
+	/**
+	 * Checks whether this is a key event that can stop PIE session.
+	 *
+	 * @param KeyEvent - Key event to test.
+	 * @returns True, if this key event can stop PIE session.
+	 */
+	bool IsStopPlaySessionEvent(const FKeyEvent& KeyEvent) const;
+#endif
+
+	/**
+	 * Checks whether corresponding ImGui context has an active item (holding cursor focus).
+	 *
+	 * @returns True, if corresponding context has an active item.
+	 */
 	bool HasImGuiActiveItem() const;
 
 private:
@@ -164,5 +191,9 @@ private:
 
 	int32 ContextIndex = -1;
 
+#if WITH_EDITOR
+	TSharedPtr<FUICommandInfo> StopPlaySessionCommandInfo;
+#endif
+
 	friend class FImGuiInputHandlerFactory;
 };