mirror of
https://github.com/status-im/react-native.git
synced 2025-02-23 22:58:19 +00:00
94d49e544d
Summary: We are moving to more stable APIs removing all mentiones of the effort name from the codebase. Reviewed By: mdvacca Differential Revision: D12912894 fbshipit-source-id: 4a0c6b9e7454b8b14e62d419e9e9311dc0c56e7a
94 lines
2.8 KiB
C++
94 lines
2.8 KiB
C++
/**
|
|
* Copyright (c) Facebook, Inc. and its affiliates.
|
|
*
|
|
* This source code is licensed under the MIT license found in the
|
|
* LICENSE file in the root directory of this source tree.
|
|
*/
|
|
#pragma once
|
|
|
|
#include <memory>
|
|
#include <mutex>
|
|
|
|
#include <folly/dynamic.h>
|
|
#include <react/events/EventDispatcher.h>
|
|
#include <react/events/primitives.h>
|
|
|
|
namespace facebook {
|
|
namespace react {
|
|
|
|
class EventEmitter;
|
|
|
|
using SharedEventEmitter = std::shared_ptr<const EventEmitter>;
|
|
|
|
/*
|
|
* Base class for all particular typed event handlers.
|
|
* Stores a pointer to `EventTarget` identifying a particular component and
|
|
* a weak pointer to `EventDispatcher` which is responsible for delivering the
|
|
* event.
|
|
*
|
|
* Note: Retaining an `EventTarget` does *not* guarantee that actual event
|
|
* target exists and/or valid in JavaScript realm. The `EventTarget` retains an
|
|
* `EventTargetWrapper` which wraps JavaScript object in `unsafe-unretained`
|
|
* manner. Retaining the `EventTarget` *does* indicate that we can use that to
|
|
* get an actual JavaScript object from that in the future *ensuring safety
|
|
* beforehand somehow*; JSI maintains `WeakObject` object as long as we retain
|
|
* the `EventTarget`. All `EventTarget` instances must be deallocated before
|
|
* stopping JavaScript machine.
|
|
*/
|
|
class EventEmitter {
|
|
/*
|
|
* We have to repeat `Tag` type definition here because `events` module does
|
|
* not depend on `core` module (and should not).
|
|
*/
|
|
using Tag = int32_t;
|
|
|
|
public:
|
|
static std::recursive_mutex &DispatchMutex();
|
|
|
|
EventEmitter(
|
|
SharedEventTarget eventTarget,
|
|
Tag tag,
|
|
WeakEventDispatcher eventDispatcher);
|
|
|
|
virtual ~EventEmitter() = default;
|
|
|
|
/*
|
|
* `DispatchMutex` must be acquired before calling.
|
|
* Enables/disables event emitter.
|
|
* Enabled event emitter retains a pointer to `eventTarget` strongly (as
|
|
* `std::shared_ptr`) whereas disabled one weakly (as `std::weak_ptr`).
|
|
* The enable state is additive; a number of `enable` calls should be equal to
|
|
* a number of `disable` calls to release the event target.
|
|
*/
|
|
void enable() const;
|
|
void disable() const;
|
|
|
|
protected:
|
|
#ifdef ANDROID
|
|
// We need this temporarily due to lack of Java-counterparts for particular
|
|
// subclasses.
|
|
public:
|
|
#endif
|
|
|
|
/*
|
|
* Initates an event delivery process.
|
|
* Is used by particular subclasses only.
|
|
*/
|
|
void dispatchEvent(
|
|
const std::string &type,
|
|
const folly::dynamic &payload = folly::dynamic::object(),
|
|
const EventPriority &priority = EventPriority::AsynchronousBatched) const;
|
|
|
|
private:
|
|
void toggleEventTargetOwnership_() const;
|
|
|
|
mutable SharedEventTarget eventTarget_;
|
|
mutable WeakEventTarget weakEventTarget_;
|
|
Tag tag_;
|
|
WeakEventDispatcher eventDispatcher_;
|
|
mutable int enableCounter_{0};
|
|
};
|
|
|
|
} // namespace react
|
|
} // namespace facebook
|