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SYS_MessageBus.subscribeOncePublic() method

Public message bus: subscribe to a message once

Signature

function subscribeOncePublic(
	topic: string,
	callbackFn: (message: any) => void,
): ISYS_MessageBusTask;

Parameters

Parameter	Type	Description
topic	string	Theme
callbackFn	(message: any) => void	Callback after receiving the message

Returns

ISYS_MessageBusTask

Message bus task

Example

// 1. 在公共总线注册单次订阅
let received = null;
eda.sys_MessageBus.subscribeOncePublic('嘉立创示例_公共单次订阅', (message) => {
	received = message;
});

// 2. 连续两条公共广播：只有第一条触发
eda.sys_MessageBus.publishPublic('嘉立创示例_公共单次订阅', '首次广播');
eda.sys_MessageBus.publishPublic('嘉立创示例_公共单次订阅', '第二次广播');
console.log('实际收到：', received);

// 3. 私有总线的 publish 与公共订阅互不相通（隔离验证）
eda.sys_MessageBus.publish('嘉立创示例_公共单次订阅', '私有消息');
console.log('私有消息到达后仍停留在：', received);