Files
react-native/ReactCommon/fabric/core/events/EventTarget.cpp
Valentin Shergin 9a64755a18 Fabric: events module was merged into core module
Summary: That's bummer that we have to do it, but it's actually reasonable. Files in `core` and `events` depend on each other creating circular dependencies and other similar hard problem.

Reviewed By: mdvacca

Differential Revision: D14195022

fbshipit-source-id: 96a44ae28631cc9ccd7d7de72a94526f9e0dd12a
2019-02-25 19:12:08 -08:00

67 lines
1.9 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.
*/
#include "EventTarget.h"
namespace facebook {
namespace react {
using Tag = EventTarget::Tag;
EventTarget::EventTarget(
jsi::Runtime &runtime,
const jsi::Value &instanceHandle,
Tag tag)
: weakInstanceHandle_(
jsi::WeakObject(runtime, instanceHandle.asObject(runtime))),
strongInstanceHandle_(jsi::Value::null()),
tag_(tag) {}
void EventTarget::setEnabled(bool enabled) const {
enabled_ = enabled;
}
void EventTarget::retain(jsi::Runtime &runtime) const {
if (!enabled_) {
return;
}
strongInstanceHandle_ = weakInstanceHandle_.lock(runtime);
// Having a `null` or `undefined` object here indicates that
// `weakInstanceHandle_` was already deallocated. This should *not* happen by
// design, and if it happens it's a severe problem. This basically means that
// particular implementation of JSI was able to detect this inconsistency and
// dealt with it, but some JSI implementation may not support this feature and
// that case will lead to a crash in those environments.
assert(!strongInstanceHandle_.isNull());
assert(!strongInstanceHandle_.isUndefined());
}
void EventTarget::release(jsi::Runtime &runtime) const {
// The method does not use `jsi::Runtime` reference.
// It takes it only to ensure thread-safety (if the caller has the reference,
// we are on a proper thread).
strongInstanceHandle_ = jsi::Value::null();
}
jsi::Value EventTarget::getInstanceHandle(jsi::Runtime &runtime) const {
if (strongInstanceHandle_.isNull()) {
// The `instanceHandle` is not retained.
return jsi::Value::null();
}
return jsi::Value(runtime, strongInstanceHandle_);
}
Tag EventTarget::getTag() const {
return tag_;
}
} // namespace react
} // namespace facebook