Function fnEventFlagRequestHandler

packages/message/common.ts:35–52

(ev: Event)

  // 监听 inject/content 发来的请求 eventFlag 的消息
  let ready = 0;
  const fnEventFlagRequestHandler: EventListener = (ev: Event) => {
    if (!(ev instanceof CustomEvent)) return;

    switch (ev.detail?.action) {
      case "receivedEventFlag":
        // 对方已收到 eventFlag
        ready += 1;
        if (ready >= readyCount) {
          // 已收到两个环境的请求，移除监听
          pageRemoveEventListener(messageFlag, fnEventFlagRequestHandler);
        }
        break;
      case "requestEventFlag":
        // 广播通信 flag 给 inject/content
        pageDispatchCustomEvent(messageFlag, { action: "broadcastEventFlag", eventFlag: eventFlag, extensionEnv });
        break;
    }
  };

  // 设置事件，然后广播通信 flag 给 inject/content
  pageAddEventListener(messageFlag, fnEventFlagRequestHandler);