我想向所有设备发送消息，但我只向一个设备发送消息，这是我发送消息的方式:我只能向一个用户发送消息，当我在我的发送消息方法中删除它时:
I want to send a message to all device but I only send to one device this is how I send a message : I only can send message to one user , when I remove this at my method to send a message:
json.put("to", tokenId.trim());
当我有这条线时，消息不会发送给任何人我只向一个用户发送消息.我如何向每个人发送消息?
a message is not send to nobody when I have this line I send a message to only one user . How I can send a message to every one ?
static void send_FCM_Notification(String tokenId, String server_key, String message) {
try {
URL url = new URL(FCM_URL);
// create connection.
HttpURLConnection conn;
conn = (HttpURLConnection) url.openConnection();
conn.setUseCaches(false);
conn.setDoInput(true);
conn.setDoOutput(true);
//set method as POST or GET
conn.setRequestMethod("POST");
//pass FCM server key
conn.setRequestProperty("Authorization", "key=" + server_key);
//Specify Message Format
conn.setRequestProperty("Content-Type", "application/json");
//Create JSON Object & pass value
JSONObject infoJson = new JSONObject();
infoJson.put("title", "Wiadomosc z serwera");
infoJson.put("sound", "default");
infoJson.put("icon", "ic_launcher");
infoJson.put("body", message);
JSONObject json = new JSONObject();
json.put("to", tokenId.trim());
json.put("notification", infoJson);
OutputStreamWriter wr = new OutputStreamWriter(conn.getOutputStream());
wr.write(json.toString());
wr.flush();
int status = 0;
if (null != conn) {
status = conn.getResponseCode();
}
if (status != 0) {
if (status == 200) {
//SUCCESS message
BufferedReader reader = new BufferedReader(new InputStreamReader(conn.getInputStream()));
System.out.println("Android Notification Response : " + reader.readLine());
} else if (status == 401) {
//client side error
System.out.println("Notification Response : TokenId : " + tokenId + " Error occurred : 401");
} else if (status == 501) {
//server side error
System.out.println("Notification Response : [ errorCode=ServerError ] TokenId : " + tokenId);
} else if (status == 503) {
//server side error
System.out.println("Notification Response : FCM Service is Unavailable TokenId : " + tokenId);
}
}
} catch (MalformedURLException mlfexception) {
// Prototcal Error
System.out.println("Error occurred while sending push Notification!.." + mlfexception.getMessage());
} catch (IOException mlfexception) {
//URL problem
System.out.println("Reading URL, Error occurred while sending push Notification!.." + mlfexception.getMessage());
} catch (JSONException jsonexception) {
//Message format error
System.out.println("Message Format, Error occurred while sending push Notification!.." + jsonexception.getMessage());
} catch (Exception exception) {
//General Error or exception.
System.out.println("Error occurred while sending push Notification!.." + exception.getMessage());
}
}
Firebase 支持所谓的 topics
Firebase supports what is called topics
因此，您可以向某个主题发送消息，订阅该主题的所有设备都会收到推送.
So you can send a message to a topic and all the devices subscribed to that topic will get the push.
您可以有一个名为 all 的主题，然后将每个设备注册到该主题.
You can have a topic called all and then register each device to that.
这是您的注册方式
FirebaseMessaging.getInstance().subscribeToTopic("all");
然后，您只需向该主题发送通知，您的所有用户都会收到它.
Then you can just fire notifications to that topic and all your users will get it.
然后替换这一行
json.put("to", tokenId.trim());
与
json.put("to", "/topics/your-topic-name");
在这种情况下，您的主题名称是 all
In this case your topic name is all
这篇关于Java Firebase 云消息.向所有人发送消息的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持跟版网！