使用BroadcastReceiver获取Android中断开的WiFi网络的SSID？

Question

我有以下BroadcastRecevier:

public class WiFiConnectionEventsReceiver extends BroadcastReceiver {

    private static final String TAG = WiFiConnectionEventsReceiver.class.getSimpleName();

    @Override
    public void onReceive(Context context, @NonNull Intent intent) {
        Log.v(TAG, "action: " + intent.getAction());
        Log.v(TAG, "component: " + intent.getComponent());
        Bundle extras = intent.getExtras();
        if (extras != null) {
            for (String key : extras.keySet()) {
                Log.v(TAG, "key [" + key + "]: " +
                        extras.get(key));
            }
        } else {
            Log.v(TAG, "no extras");
        }

        ConnectivityManager conMan = (ConnectivityManager) context.getSystemService(Context.CONNECTIVITY_SERVICE);
        NetworkInfo netInfo = conMan.getActiveNetworkInfo();
        if (netInfo != null && netInfo.getType() == ConnectivityManager.TYPE_WIFI) {
            Log.d("NetworkInfo", "Have Wifi Connection");
            Log.d("NetworkInfo", netInfo.getExtraInfo());
            Log.d("NetworkInfo", netInfo.getTypeName());
        }
        else {
            Log.d("NetworkInfo", "Don't have Wifi Connection");
            Log.d("NetworkInfo", netInfo.getExtraInfo());
            Log.d("NetworkInfo", netInfo.getTypeName());
        }

        WifiManager wifiManager = (WifiManager) context.getSystemService(Context.WIFI_SERVICE);
        Log.d("WifiInfo",  wifiManager.getConnectionInfo().toString());
    }
}

它接收网络连接和断开连接事件.

当它连接到WiFi网络时,我能够轻松获得网络的SSID.

但我希望能够在网络断开时获得WiFi网络的SSID(无需存储先前连接的网络,然后以这种方式匹配它们等).这可能吗？

WiFi连接时记录日志:

V/WiFiConnectionEventsReceiver: action: android.net.conn.CONNECTIVITY_CHANGE
V/WiFiConnectionEventsReceiver: component: ComponentInfo{com.example.test/com.example.test.WiFiConnectionEventsReceiver}
V/WiFiConnectionEventsReceiver: key [networkInfo]: [type: WIFI[], state: CONNECTED/CONNECTED, reason: (unspecified), extra: "SKY123”, roaming: false, failover: false, isAvailable: true]
V/WiFiConnectionEventsReceiver: key [networkType]: 1
V/WiFiConnectionEventsReceiver: key [inetCondition]: 100
V/WiFiConnectionEventsReceiver: key [extraInfo]: "SKY123”
D/NetworkInfo: Have Wifi Connection
D/NetworkInfo: "SKY123”
D/NetworkInfo: WIFI
D/WifiInfo: SSID: SKY123, BSSID: 10:40:03:ad:6x:c9, MAC: 02:00:00:00:00:00, Supplicant state: COMPLETED, RSSI: -79, Link speed: 43Mbps, Frequency: 2412MHz, Net ID: 1, Metered hint: false, score: 60

WiFi断开连接时记录(注意未知的SSID):

V/WiFiConnectionEventsReceiver: action: android.net.conn.CONNECTIVITY_CHANGE
V/WiFiConnectionEventsReceiver: component: ComponentInfo{com.example.test/com.example.test.WiFiConnectionEventsReceiver}
V/WiFiConnectionEventsReceiver: key [networkInfo]: [type: WIFI[], state: DISCONNECTED/DISCONNECTED, reason: (unspecified), extra: <unknown ssid>, roaming: false, failover: false, isAvailable: true]
V/WiFiConnectionEventsReceiver: key [networkType]: 1
V/WiFiConnectionEventsReceiver: key [inetCondition]: 0
V/WiFiConnectionEventsReceiver: key [extraInfo]: <unknown ssid>
V/WiFiConnectionEventsReceiver: key [noConnectivity]: true
D/NetworkInfo: Don't have Wifi Connection
D/NetworkInfo: id
D/NetworkInfo: MOBILE
D/WifiInfo: SSID: <unknown ssid>, BSSID: <none>, MAC: 02:00:00:00:00:00, Supplicant state: COMPLETED, RSSI: -127, Link speed: -1Mbps, Frequency: -1MHz, Net ID: -1, Metered hint: false, score: 0

我想要这个信息的原因是我希望能够跟踪用户在每个网络上的WiFi使用情况 - 连接和断开连接时间.

如果没有断开连接的网络的SSID,我能想到的唯一方法就是:

if (WiFi network ABC disconnected)
  if (if previous stored connection for WiFi network ABC has no disconnection time)
      set WiFI network ABC disconnection time to now

然而,上述方法感觉不稳定,例如,如果由于某种原因错过了WiFi断开事件等等

Answer 1

这不可能。当onReceive调用时，连接已经丢失，当前信息显示没有连接。

onRecieve另请注意，在收到断开连接信息后，您可能会立即接到另一个电话。从规格来看：

连接性_操作

[...]

如果这是从断开的网络进行故障转移的结果的连接，则 FAILOVER_CONNECTION 布尔值额外设置为 true。

对于连接丢失，如果连接管理器正在尝试连接（或已经连接）到另一个网络，则新网络的 NetworkInfo 也会作为额外信息传递。这让广播的任何接收者知道他们不必告诉用户没有数据流量是可能的。相反，接收方应该很快就会收到另一个广播，表明故障转移尝试成功（因此仍然存在总体数据连接），或者故障转移尝试失败，这意味着所有连接都已丢失。

[...]