react-native-web/dist/cjs/vendor/react-native/EventEmitter/NativeEventEmitter.js

React Native for Web

/**
 * Copyright (c) Meta Platforms, Inc. and affiliates.
 *
 * This source code is licensed under the MIT license found in the
 * LICENSE file in the root directory of this source tree.
 *
 * 
 * @format
 */

'use strict';

var _interopRequireDefault = require("@babel/runtime/helpers/interopRequireDefault").default;
exports.__esModule = true;
exports.default = void 0;
var _Platform = _interopRequireDefault(require("../../../exports/Platform"));
var _RCTDeviceEventEmitter = _interopRequireDefault(require("./RCTDeviceEventEmitter"));
var _invariant = _interopRequireDefault(require("fbjs/lib/invariant"));
/**
 * `NativeEventEmitter` is intended for use by Native Modules to emit events to
 * JavaScript listeners. If a `NativeModule` is supplied to the constructor, it
 * will be notified (via `addListener` and `removeListeners`) when the listener
 * count changes to manage "native memory".
 *
 * Currently, all native events are fired via a global `RCTDeviceEventEmitter`.
 * This means event names must be globally unique, and it means that call sites
 * can theoretically listen to `RCTDeviceEventEmitter` (although discouraged).
 */
class NativeEventEmitter {
  constructor(nativeModule) {
    if (_Platform.default.OS === 'ios') {
      (0, _invariant.default)(nativeModule != null, '`new NativeEventEmitter()` requires a non-null argument.');
      this._nativeModule = nativeModule;
    }
  }
  addListener(eventType, listener, context) {
    var _this$_nativeModule;
    (_this$_nativeModule = this._nativeModule) == null ? void 0 : _this$_nativeModule.addListener(eventType);
    var subscription = _RCTDeviceEventEmitter.default.addListener(eventType, listener, context);
    return {
      remove: () => {
        if (subscription != null) {
          var _this$_nativeModule2;
          (_this$_nativeModule2 = this._nativeModule) == null ? void 0 : _this$_nativeModule2.removeListeners(1);
          // $FlowFixMe[incompatible-use]
          subscription.remove();
          subscription = null;
        }
      }
    };
  }

  /**
   * @deprecated Use `remove` on the EventSubscription from `addListener`.
   */
  removeListener(eventType, listener) {
    var _this$_nativeModule3;
    (_this$_nativeModule3 = this._nativeModule) == null ? void 0 : _this$_nativeModule3.removeListeners(1);
    // NOTE: This will report a deprecation notice via `console.error`.
    // $FlowFixMe[prop-missing] - `removeListener` exists but is deprecated.
    _RCTDeviceEventEmitter.default.removeListener(eventType, listener);
  }
  emit(eventType) {
    for (var _len = arguments.length, args = new Array(_len > 1 ? _len - 1 : 0), _key = 1; _key < _len; _key++) {
      args[_key - 1] = arguments[_key];
    }
    // Generally, `RCTDeviceEventEmitter` is directly invoked. But this is
    // included for completeness.
    _RCTDeviceEventEmitter.default.emit(eventType, ...args);
  }
  removeAllListeners(eventType) {
    var _this$_nativeModule4;
    (0, _invariant.default)(eventType != null, '`NativeEventEmitter.removeAllListener()` requires a non-null argument.');
    (_this$_nativeModule4 = this._nativeModule) == null ? void 0 : _this$_nativeModule4.removeListeners(this.listenerCount(eventType));
    _RCTDeviceEventEmitter.default.removeAllListeners(eventType);
  }
  listenerCount(eventType) {
    return _RCTDeviceEventEmitter.default.listenerCount(eventType);
  }
}
exports.default = NativeEventEmitter;
module.exports = exports.default;