[wifi_signal] Update signal strength immediately on WiFi connect/disconnect (#12347)

esphome/components/wifi_signal/sensor.py

@@ -1,5 +1,5 @@
 import esphome.codegen as cg
-from esphome.components import sensor
+from esphome.components import sensor, wifi
 import esphome.config_validation as cv
 from esphome.const import (
     DEVICE_CLASS_SIGNAL_STRENGTH,
@@ -25,5 +25,6 @@ CONFIG_SCHEMA = sensor.sensor_schema(
 
 
 async def to_code(config):
+    wifi.request_wifi_listeners()
     var = await sensor.new_sensor(config)
     await cg.register_component(var, config)

esphome/components/wifi_signal/wifi_signal_sensor.cpp

@@ -2,13 +2,11 @@
 #ifdef USE_WIFI
 #include "esphome/core/log.h"
 
-namespace esphome {
-namespace wifi_signal {
+namespace esphome::wifi_signal {
 
 static const char *const TAG = "wifi_signal.sensor";
 
 void WiFiSignalSensor::dump_config() { LOG_SENSOR("", "WiFi Signal", this); }
 
-}  // namespace wifi_signal
-}  // namespace esphome
+}  // namespace esphome::wifi_signal
 #endif

esphome/components/wifi_signal/wifi_signal_sensor.h

@@ -5,17 +5,19 @@
 #include "esphome/components/sensor/sensor.h"
 #include "esphome/components/wifi/wifi_component.h"
 #ifdef USE_WIFI
-namespace esphome {
-namespace wifi_signal {
+namespace esphome::wifi_signal {
 
-class WiFiSignalSensor : public sensor::Sensor, public PollingComponent {
+class WiFiSignalSensor : public sensor::Sensor, public PollingComponent, public wifi::WiFiConnectStateListener {
  public:
+  void setup() override { wifi::global_wifi_component->add_connect_state_listener(this); }
   void update() override { this->publish_state(wifi::global_wifi_component->wifi_rssi()); }
   void dump_config() override;
 
   float get_setup_priority() const override { return setup_priority::AFTER_WIFI; }
+
+  // WiFiConnectStateListener interface - update RSSI immediately on connect
+  void on_wifi_connect_state(const std::string &ssid, const wifi::bssid_t &bssid) override { this->update(); }
 };
 
-}  // namespace wifi_signal
-}  // namespace esphome
+}  // namespace esphome::wifi_signal
 #endif