UReactBridgeSenderComponent

Source: SampleProject/Plugins/UnrealReactBridge/Source/UnrealReactBridge/Public/ReactBridgeSenderComponent.h

UActorComponent that pushes typed events from gameplay to React. Drop it on any Actor; choose a target HUD with TargetBridgeName or leave empty to broadcast to every active layer.

• UCLASS: ClassGroup = ("Web HUD"), BlueprintSpawnableComponent
• Display name: React Bridge Sender
• Add via: Components panel → Add → search "React Bridge Sender"

Properties

Property	Type	Category	Notes
TargetBridgeName	FString (EditAnywhere, BlueprintReadWrite)	React Bridge	Routes Push calls to the named layer. Empty = broadcast to every registered HUD widget. Case-sensitive; must match an Add Web HUD Name or UWebHUDWidget::BridgeName.

Push helpers

All Push helpers live under category React Bridge|Push. They wrap the value (except PushMap / PushRaw) in { "value": ... } and dispatch through UUnrealReactBridgeSubsystem. The React side reads event.detail.

Helper	Signature	event.detail shape
PushFloat	void PushFloat(const FString& EventName, float Value)	{ "value": 75 }
PushInt	void PushInt(const FString& EventName, int32 Value)	{ "value": 42 }
PushString	void PushString(const FString& EventName, const FString& Value)	{ "value": "alice" }
PushBool	void PushBool(const FString& EventName, bool Value)	{ "value": true }
PushVector	void PushVector(const FString& EventName, FVector Value)	{ "value": { "X": 1, "Y": 2, "Z": 3 } }
PushMap	void PushMap(const FString& EventName, const TMap<FString, FString>& Pairs)	flat { "k1": "v1", "k2": "v2" } (no envelope; key order non-deterministic)
PushRaw	void PushRaw(const FString& EventName, const FString& JsonData)	<JsonData> verbatim

Parameters (all helpers)

Param	Type	Required	Notes
EventName	FString	yes	Case-sensitive; matches React window.ue.bridge.on(EventName, ...)
Value / Pairs / JsonData	varies	yes	Wrapped under value for typed helpers; passed through verbatim for PushMap / PushRaw

Returns — void. Push helpers fire-and-forget; there is no synchronous ack.

WARNING

PushMap emits a flat object — there is no value envelope. React clients must read keys by name, not iterate by index, because key order on the wire is non-deterministic.

WARNING

PushRaw does not validate JSON. Malformed input will reach the React side and fail to parse — see /reference/types#fbridgeerrorinfo (JSONParseError).

TIP

PushStruct is C++ only — it's a header-only template, not UFUNCTION-exposed:

template<typename T>
void PushStruct(const FString& EventName, const T& Value);

It uses FJsonObjectConverter::UStructToJsonObjectString under the hood and wraps the resulting object under "value". From Blueprint, hand-build the JSON and use PushRaw.

Example

ReactBridgeSender (component)
  TargetBridgeName: "HpBar"

Tick (every 100ms)
  └─ PushFloat
       EventName: "player:health"
       Value:     CurrentHP / MaxHP

// C++ equivalent
Sender->TargetBridgeName = TEXT("HpBar");
Sender->PushFloat(TEXT("player:health"), CurrentHP / MaxHP);

See also

• /guide/push-data — patterns for game-to-React data flow
• /reference/bridge-protocol#typed-payload-conventions — wire format details
• /reference/bp-receiver — the reverse direction (React → UE)