Auto-focus system now not dependent on MenuStack, just FocusableUserWidget

This allows you to have other FocusableUserWidget subclasses (e.g. single dialogs)
automatically figure out focus between each other

Source/StevesUEHelpers/Private/StevesGameSubsystem.cpp

@@ -87,9 +87,9 @@ void UStevesGameSubsystem::OnInputDetectorModeChanged(int PlayerIndex, EInputMod
     OnInputModeChanged.Broadcast(PlayerIndex, NewMode);
 }
 
-FMenuSystem* UStevesGameSubsystem::GetMenuSystem()
+FFocusSystem* UStevesGameSubsystem::GetFocusSystem()
 {
-    return &MenuSystem;
+    return &FocusSystem;
 }
 
 UStevesGameSubsystem::FInputModeDetector::FInputModeDetector()

Source/StevesUEHelpers/Private/StevesUI/FocusSystem.cpp

@@ -0,0 +1,75 @@
+#include "StevesUI/FocusSystem.h"
+#include "StevesUI/FocusableUserWidget.h"
+
+DEFINE_LOG_CATEGORY(LogFocusSystem)
+
+TWeakObjectPtr<UFocusableUserWidget> FFocusSystem::GetHighestFocusPriority()
+{
+    int Highest = -999;
+    TWeakObjectPtr<UFocusableUserWidget> Ret;
+    
+    for (auto && S : ActiveAutoFocusWidgets)
+    {
+        if (S.IsValid() && S->IsRequestingFocus() && S->GetAutomaticFocusPriority() > Highest)
+        {
+            Highest = S->GetAutomaticFocusPriority();
+            Ret = S;
+        }
+    }
+        
+    return Ret;
+}
+
+void FFocusSystem::FocusableWidgetConstructed(UFocusableUserWidget* Widget)
+{
+    UE_LOG(LogFocusSystem, Display, TEXT("FocusableUserWidget %s opened"), *Widget->GetName());
+    // check to make sure we never dupe, shouldn't normally be a problem
+    // but let's just be safe, there will never be that many
+    bool bPresent = false;    
+    for (auto && S : ActiveAutoFocusWidgets)
+    {
+        if (S.Get() == Widget)
+        {
+            bPresent = true;
+            break;
+        }
+    }
+    if (!bPresent)
+        ActiveAutoFocusWidgets.Add(Widget);
+
+    if (Widget->IsRequestingFocus())
+    {
+        auto Highest = GetHighestFocusPriority();
+        if (!Highest.IsValid() || Highest->GetAutomaticFocusPriority() <= Widget->GetAutomaticFocusPriority())
+        {
+            // give new stack the focus if it's equal or higher priority than anything else
+            UE_LOG(LogFocusSystem, Display, TEXT("Giving focus to %s"), *Widget->GetName());
+            Widget->TakeFocusIfDesired();
+        }        
+    }
+}
+
+void FFocusSystem::FocusableWidgetDestructed(UFocusableUserWidget* Widget)
+{
+    UE_LOG(LogFocusSystem, Display, TEXT("FocusableUserWidget %s closed"), *Widget->GetName());
+    
+    for (int i = 0; i < ActiveAutoFocusWidgets.Num(); ++i)
+    {
+        if (ActiveAutoFocusWidgets[i].Get() == Widget)
+        {
+            ActiveAutoFocusWidgets.RemoveAt(i);
+            break;
+        }
+    }
+
+    // if the menu closing had focus, give it to the highest remaining stack
+    if (Widget->HasFocusedDescendants())
+    {
+        auto Highest = GetHighestFocusPriority();
+        if (Highest.IsValid())
+        {
+            UE_LOG(LogFocusSystem, Display, TEXT("Giving focus to %s"), *Highest->GetName());
+            Highest->TakeFocusIfDesired();
+        }       
+    }
+}

Source/StevesUEHelpers/Private/StevesUI/FocusableUserWidget.cpp

@@ -1,7 +1,53 @@
 #include "StevesUI/FocusableUserWidget.h"
 
+#include "StevesUEHelpers.h"
+
 void UFocusableUserWidget::SetFocusProperly_Implementation()
 {
     // Default is to call normal
     SetFocus();
 }
+
+
+bool UFocusableUserWidget::IsRequestingFocus_Implementation() const
+{
+    // Subclasses can override this
+    return bEnableAutomaticFocus;    
+}
+
+bool UFocusableUserWidget::TakeFocusIfDesired_Implementation()
+{
+    auto GS = GetStevesGameSubsystem(GetWorld());
+    if (IsRequestingFocus() &&
+        GS && (GS->GetLastInputModeUsed() != EInputMode::Gamepad || GS->GetLastInputModeUsed() != EInputMode::Keyboard))
+    {
+        SetFocusProperly();
+        return true;
+    }
+    return false;
+}
+
+void UFocusableUserWidget::NativeConstruct()
+{
+    Super::NativeConstruct();
+
+    if (bEnableAutomaticFocus)
+    {
+        auto GS = GetStevesGameSubsystem(GetWorld());
+        if (GS)
+            GS->GetFocusSystem()->FocusableWidgetConstructed(this);               
+    }
+}
+
+void UFocusableUserWidget::NativeDestruct()
+{
+    Super::NativeDestruct();
+
+    if (bEnableAutomaticFocus)
+    {
+        auto GS = GetStevesGameSubsystem(GetWorld());
+        if (GS)
+            GS->GetFocusSystem()->FocusableWidgetDestructed(this);               
+    }
+
+}

Source/StevesUEHelpers/Private/StevesUI/MenuBase.cpp

@@ -134,14 +134,3 @@ void UMenuBase::Open(bool bIsRegain)
     TakeFocusIfDesired();
     
 }
-
-void UMenuBase::TakeFocusIfDesired()
-{
-    auto GS = GetStevesGameSubsystem(GetWorld());
-    if (bRequestFocus &&
-        GS && (GS->GetLastInputModeUsed() != EInputMode::Gamepad || GS->GetLastInputModeUsed() != EInputMode::Keyboard))
-    {
-        SetFocusProperly();
-    }    
-}
-

Source/StevesUEHelpers/Private/StevesUI/MenuStack.cpp

@@ -230,10 +230,7 @@ void UMenuStack::PopMenuIfTop(UMenuBase* UiMenuBase, bool bWasCancel)
 
 void UMenuStack::FirstMenuOpened()
 {
-    // tell menu system
-    auto GS = GetStevesGameSubsystem(GetWorld());
-    if (GS)
-        GS->GetMenuSystem()->MenuStackOpened(this);       
+    // Nothing to do now but keep for future use
 }
 
 void UMenuStack::RemoveFromParent()
@@ -247,11 +244,12 @@ void UMenuStack::RemoveFromParent()
     
     Super::RemoveFromParent();
 
-    // tell menu system if we're in-game (this gets called in editor too)
-    auto GS = GetStevesGameSubsystem(GetWorld());
-    if (GS)
-        GS->GetMenuSystem()->MenuStackClosed(this);
-    
+}
+
+UMenuStack::UMenuStack()
+{
+    // Default to enabling automatic focus for menus (can still be overridden in serialized properties)
+    bEnableAutomaticFocus = true;
 }
 
 void UMenuStack::LastMenuClosed(bool bWasCancel)
@@ -277,19 +275,12 @@ void UMenuStack::CloseAll(bool bWasCancel)
     LastMenuClosed(bWasCancel);
 }
 
-bool UMenuStack::IsRequestingFocus() const
+bool UMenuStack::IsRequestingFocus_Implementation() const
 {
+    // Delegate to top menu
     return Menus.Num() > 0 && Menus.Last()->IsRequestingFocus();
 }
 
-void UMenuStack::TakeFocusIfDesired()
-{
-    if (IsRequestingFocus())
-    {
-        Menus.Last()->TakeFocusIfDesired();
-    }
-}
-
 void UMenuStack::SetFocusProperly_Implementation()
 {
     // Delegate to top menu

Source/StevesUEHelpers/Private/StevesUI/MenuSystem.cpp

@@ -1,75 +0,0 @@
-#include "StevesUI/MenuSystem.h"
-#include "StevesUI/MenuStack.h"
-
-DEFINE_LOG_CATEGORY(LogMenuSystem)
-
-TWeakObjectPtr<UMenuStack> FMenuSystem::GetHighestFocusPriority()
-{
-    int Highest = -999;
-    TWeakObjectPtr<UMenuStack> Ret;
-    
-    for (auto && S : ActiveMenuStacks)
-    {
-        if (S.IsValid() && S->IsRequestingFocus() && S->FocusPriority > Highest)
-        {
-            Highest = S->FocusPriority;
-            Ret = S;
-        }
-    }
-        
-    return Ret;
-}
-
-void FMenuSystem::MenuStackOpened(UMenuStack* Stack)
-{
-    UE_LOG(LogMenuSystem, Display, TEXT("MenuStack %s opened"), *Stack->GetName());
-    // check to make sure we never dupe, shouldn't normally be a problem
-    // but let's just be safe, there will never be that many
-    bool bPresent = false;    
-    for (auto && S : ActiveMenuStacks)
-    {
-        if (S.Get() == Stack)
-        {
-            bPresent = true;
-            break;
-        }
-    }
-    if (!bPresent)
-        ActiveMenuStacks.Add(Stack);
-
-    if (Stack->IsRequestingFocus())
-    {
-        auto Highest = GetHighestFocusPriority();
-        if (!Highest.IsValid() || Highest->FocusPriority <= Stack->FocusPriority)
-        {
-            // give new stack the focus if it's equal or higher priority than anything else
-            UE_LOG(LogMenuSystem, Display, TEXT("Giving focus to MenuStack %s"), *Stack->GetName());
-            Stack->TakeFocusIfDesired();
-        }        
-    }
-}
-
-void FMenuSystem::MenuStackClosed(UMenuStack* Stack)
-{
-    UE_LOG(LogMenuSystem, Display, TEXT("MenuStack %s closed"), *Stack->GetName());
-    
-    for (int i = 0; i < ActiveMenuStacks.Num(); ++i)
-    {
-        if (ActiveMenuStacks[i].Get() == Stack)
-        {
-            ActiveMenuStacks.RemoveAt(i);
-            break;
-        }
-    }
-
-    // if the menu closing had focus, give it to the highest remaining stack
-    if (Stack->HasFocusedDescendants())
-    {
-        auto Highest = GetHighestFocusPriority();
-        if (Highest.IsValid())
-        {
-            UE_LOG(LogMenuSystem, Display, TEXT("Giving focus to MenuStack %s"), *Highest->GetName());
-            Highest->TakeFocusIfDesired();
-        }       
-    }
-}

Source/StevesUEHelpers/Public/StevesGameSubsystem.h

@@ -5,7 +5,7 @@
 #include "InputCoreTypes.h"
 #include "Framework/Application/IInputProcessor.h"
 #include "StevesHelperCommon.h"
-#include "StevesUI/MenuSystem.h"
+#include "StevesUI/FocusSystem.h"
 #include "StevesUI/UiTheme.h"
 
 #include "StevesGameSubsystem.generated.h"
@@ -92,7 +92,7 @@ protected:
 
 protected:
     TSharedPtr<FInputModeDetector> InputDetector;
-    FMenuSystem MenuSystem;
+    FFocusSystem FocusSystem;
 
     UPROPERTY(BlueprintReadWrite)
     UUiTheme* DefaultUiTheme;
@@ -123,6 +123,6 @@ public:
     /// Changes the default theme to a different one
     void SetDefaultUiTheme(UUiTheme* NewTheme) { DefaultUiTheme = NewTheme; }
 
-    /// Get the global menu system
-    FMenuSystem* GetMenuSystem();
+    /// Get the global focus system
+    FFocusSystem* GetFocusSystem();
 };

Source/StevesUEHelpers/Public/StevesUI/FocusSystem.h

@@ -0,0 +1,17 @@
+#pragma once
+
+#include "CoreMinimal.h"
+
+DECLARE_LOG_CATEGORY_EXTERN(LogFocusSystem, Log, All)
+
+class FFocusSystem
+{
+protected:
+    TArray<TWeakObjectPtr<class UFocusableUserWidget>> ActiveAutoFocusWidgets;
+
+    TWeakObjectPtr<UFocusableUserWidget> GetHighestFocusPriority();
+public:
+    void FocusableWidgetConstructed(UFocusableUserWidget* Widget);
+    void FocusableWidgetDestructed(UFocusableUserWidget* Widget);
+    
+};

Source/StevesUEHelpers/Public/StevesUI/FocusableUserWidget.h

@@ -11,10 +11,40 @@ class STEVESUEHELPERS_API UFocusableUserWidget : public UUserWidget
 {
     GENERATED_BODY()
 
+protected:
+
+    /// If enabled, this widget will opt-in to the list of widgets which can be given focus
+    /// automatically when another UFocusableUserWidget with focus is removed from the viewport.
+    /// Useful for making sure something has the focus at all times without having to have cross-dependencies
+    /// between UI parts, or events everywhere
+    UPROPERTY(EditAnywhere, BlueprintReadOnly, Category="Focus")
+    bool bEnableAutomaticFocus = false;
+
+    /// If bEnableAutomaticFocus is enabled, then this is the focus priority associated with this widget.
+    /// In the event that there is more than one auto focus widget available, the highest priority widget will win. 
+    UPROPERTY(EditAnywhere, BlueprintReadOnly, Category="Focus")
+    int AutomaticFocusPriority = 0;
+
 public:
     /// UWidget::SetFocus is not virtual FFS. This does the same as SetFocus by default but can be overridden,
     /// e.g. to delegate focus to specific children
     UFUNCTION(BlueprintNativeEvent, BlueprintCallable)
     void SetFocusProperly();
-        
+
+    /// Whether this widget is *currently* requesting focus. Default is to use IsAutomaticFocusEnabled but subclasses
+    /// may override this to be volatile
+    UFUNCTION(BlueprintNativeEvent, BlueprintCallable)
+    bool IsRequestingFocus() const;
+
+    /// Tell this widget to take the focus if it desires to
+    UFUNCTION(BlueprintNativeEvent, BlueprintCallable)
+    bool TakeFocusIfDesired();
+
+    virtual bool IsAutomaticFocusEnabled() const { return bEnableAutomaticFocus; }
+    virtual int GetAutomaticFocusPriority() const { return AutomaticFocusPriority; }
+
+protected:
+    virtual void NativeConstruct() override;
+    virtual void NativeDestruct() override;
+    
 };

Source/StevesUEHelpers/Public/StevesUI/MenuBase.h

@@ -76,13 +76,8 @@ public:
     UFUNCTION(BlueprintCallable)
     void Close(bool bWasCancel);
 
-    /// Triggers this menu to take focus if appropriate
-    /// This means if the menu both requests focus, and gamepad or keyboard is in use
-    UFUNCTION(BlueprintCallable)
-    void TakeFocusIfDesired();
-
     TWeakObjectPtr<UMenuStack> GetParentStack() const { return ParentStack; }
-    bool IsRequestingFocus() const { return bRequestFocus; }
+    virtual bool IsRequestingFocus_Implementation() const override { return bRequestFocus; }
 
     void AddedToStack(UMenuStack* Parent);
     void RemovedFromStack(UMenuStack* Parent);

Source/StevesUEHelpers/Public/StevesUI/MenuStack.h

@@ -53,12 +53,6 @@ protected:
     void InputModeChanged(int PlayerIndex, EInputMode NewMode);
 
 public:
-    /// The focus priority of this stack compared to others. When a MenuStack is opened, if it has higher priority than
-    /// any existing MenuStack open, it will be given focus. When a MenuStack with focus is closed, the next highest
-    /// priority one will be given focus. 
-    UPROPERTY(EditAnywhere, BlueprintReadWrite, Category="Behaviour")
-    int FocusPriority = 0;
-
     /// Input keys which go back a level in the menu stack (default Esc and B gamepad button)
     /// Clear this list if you don't want this behaviour
     UPROPERTY(EditAnywhere, BlueprintReadOnly, Category="Input")
@@ -129,15 +123,12 @@ public:
     void CloseAll(bool bWasCancel);
 
     /// Whether the top MenuBase on this stack is requesting focus
-    UFUNCTION(BlueprintCallable)
-    bool IsRequestingFocus() const;
-    
-    /// Triggers this stack to take focus (specifically its topmost MenuBase) if appropriate
-    /// This means if both top menu on the stack requests focus, and gamepad or keyboard is in use
-    UFUNCTION(BlueprintCallable)
-    void TakeFocusIfDesired();
+    virtual bool IsRequestingFocus_Implementation() const override;
     
     virtual void SetFocusProperly_Implementation() override;
     virtual void PopMenuIfTop(UMenuBase* UiMenuBase, bool bWasCancel);
     virtual void RemoveFromParent() override;
+
+
+    UMenuStack();
 };

Source/StevesUEHelpers/Public/StevesUI/MenuSystem.h

@@ -1,17 +0,0 @@
-#pragma once
-
-#include "CoreMinimal.h"
-
-DECLARE_LOG_CATEGORY_EXTERN(LogMenuSystem, Log, All)
-
-class FMenuSystem
-{
-protected:
-    TArray<TWeakObjectPtr<class UMenuStack>> ActiveMenuStacks;
-
-    TWeakObjectPtr<UMenuStack> GetHighestFocusPriority();
-public:
-    void MenuStackOpened(UMenuStack* Stack);
-    void MenuStackClosed(UMenuStack* Stack);
-    
-};