feat: android support for ue 5.2 (#9)

Author: nattb8

.gitignore

@@ -78,3 +78,6 @@ DerivedDataCache/*
 .idea/
 
 node_modules/
+
+.DS_Store
+Content/.DS_Store

Source/Immutable/Private/Immutable/ImmutableSubsystem.cpp

@@ -22,7 +22,14 @@ void UImmutableSubsystem::Initialize(FSubsystemCollectionBase& Collection)
     IMTBL_LOG_FUNCSIG
     Super::Initialize(Collection);
 
-	ViewportCreatedHandle = UGameViewportClient::OnViewportCreated().AddUObject(this, &UImmutableSubsystem::OnViewportCreated);
+#if PLATFORM_ANDROID
+    // Enable DOM storage so we can use localStorage in the Android webview
+    GConfig->SetBool(TEXT("/Script/AndroidRuntimeSettings.AndroidRuntimeSettings"), TEXT("bEnableDomStorage"), true, GEngineIni);
+
+    EngineInitCompleteHandle = FCoreDelegates::OnFEngineLoopInitComplete.AddUObject(this, &UImmutableSubsystem::OnViewportCreated);
+#else
+    ViewportCreatedHandle = UGameViewportClient::OnViewportCreated().AddUObject(this, &UImmutableSubsystem::OnViewportCreated);
+#endif
     WorldTickHandle = FWorldDelegates::OnWorldTickStart.AddUObject(this, &UImmutableSubsystem::WorldTickStart);
 }
 

Source/Immutable/Private/Immutable/ImtblBrowserUserWidget.cpp

@@ -41,8 +41,15 @@ TSharedRef<SWidget> UImtblBrowserUserWidget::RebuildWidget()
 			ScaleBox->AddChild(Browser);
             if (UCanvasPanelSlot* RootWidgetSlot = Cast<UCanvasPanelSlot>(ScaleBox->Slot))
 			{
+#if PLATFORM_ANDROID
+                // Android webview needs to be at least 1px to 1px big to work
+                // but it can be off screen
+                RootWidgetSlot->SetAnchors(FAnchors(0, 0, 0, 0));
+                RootWidgetSlot->SetOffsets(FMargin(-1, -1, 1, 1));
+#else
 				RootWidgetSlot->SetAnchors(FAnchors(0, 0, 1, 1));
 				RootWidgetSlot->SetOffsets(DefaultOffsets);
+#endif
 			}
             if (UScaleBoxSlot* ScaleBoxSlot = Cast<UScaleBoxSlot>(Browser->Slot))
 			{
@@ -64,19 +71,25 @@ void UImtblBrowserUserWidget::BeginDestroy()
 
 void UImtblBrowserUserWidget::RemoveFromParent()
 {
+#if !PLATFORM_ANDROID
     // This is all that is needed to persist the widget state outside throughout level/world changes.
 	// Super::RemoveFromParent();
 
 	if (UPanelWidget* CurrentParent = GetParent())
 	{
 		CurrentParent->RemoveChild(this);
 	}
+#endif
 }
 
 
 void UImtblBrowserUserWidget::OnWidgetRebuilt()
 {
+#if PLATFORM_ANDROID
+    // Android webview needs to be visible to work
+#else
     SetVisibility(ESlateVisibility::Collapsed);
+#endif
     Super::OnWidgetRebuilt();
 }
 

Source/Immutable/Private/Immutable/ImtblBrowserWidget.cpp

@@ -146,6 +146,9 @@ TSharedRef<SWidget> UImtblBrowserWidget::RebuildWidget()
 			.ShowControls(false)
 			.SupportsTransparency(bSupportsTransparency)
 	        .ShowInitialThrobber(bShowInitialThrobber)
+#if PLATFORM_ANDROID
+	        .OnLoadCompleted(BIND_UOBJECT_DELEGATE(FSimpleDelegate, HandleOnLoadCompleted))
+#endif
 #if ENGINE_MAJOR_VERSION == 5 && ENGINE_MINOR_VERSION >= 1
 	        .OnConsoleMessage(BIND_UOBJECT_DELEGATE(FOnConsoleMessageDelegate, HandleOnConsoleMessage))
 #endif
@@ -165,6 +168,17 @@ TSharedRef<SWidget> UImtblBrowserWidget::RebuildWidget()
 }
 
 
+#if PLATFORM_ANDROID
+void UImtblBrowserWidget::HandleOnLoadCompleted()
+{
+	if (WebBrowserWidget->GetUrl() == "file://immutable/index.html")
+	{
+		JSConnector->SetAndroidBridgeReady();
+	}
+}
+#endif
+
+
 void UImtblBrowserWidget::OnWidgetRebuilt()
 {
     Super::OnWidgetRebuilt();

Source/Immutable/Private/Immutable/ImtblBrowserWidget.h

@@ -51,6 +51,10 @@ class IMMUTABLE_API UImtblBrowserWidget : public UWidget
     bool BindUObject(const FString& Name, UObject* Object, bool bIsPermanent = true) const;
     // Bind the JSConnector to the browser window
     void BindConnector();
+
+#if PLATFORM_ANDROID
+    void HandleOnLoadCompleted();
+#endif
 
 #if ENGINE_MAJOR_VERSION == 5 && ENGINE_MINOR_VERSION >= 1
     void HandleOnConsoleMessage(const FString& Message, const FString& Source, int32 Line, EWebBrowserConsoleLogSeverity Severity);

Source/Immutable/Private/Immutable/ImtblJSConnector.cpp

@@ -142,4 +142,12 @@ void UImtblJSConnector::SendToGame(FString Message)
 }
 
 
-
+#if PLATFORM_ANDROID
+void UImtblJSConnector::SetAndroidBridgeReady()
+{
+        IMTBL_LOG_FUNCSIG
+        bIsBridgeReady = true;
+        OnBridgeReady.Broadcast();
+        OnBridgeReady.Clear();
+}
+#endif

Source/Immutable/Private/Immutable/ImtblJSConnector.h

@@ -51,6 +51,10 @@ class IMMUTABLE_API UImtblJSConnector : public UObject
     // Bind the func to be called for executing JS. Typically by the BrowserWidget (UE5) or Blui for UE4
     FOnExecuteJsDelegate ExecuteJs;
 
+#if PLATFORM_ANDROID
+    void SetAndroidBridgeReady();
+#endif
+
 protected:
 
     // Call a JavaScript function in the connected browser

Source/Immutable/Public/Immutable/ImmutableSubsystem.h

@@ -59,6 +59,9 @@ class IMMUTABLE_API UImmutableSubsystem : public UGameInstanceSubsystem
 
     FDelegateHandle WorldTickHandle;
     FDelegateHandle ViewportCreatedHandle;
+#if PLATFORM_ANDROID
+    FDelegateHandle EngineInitCompleteHandle;
+#endif
 
     void SetupGameBridge();
 	void OnBridgeReady();