Deactivate bargraph after BLE disconnect

.gitignore

@@ -13,4 +13,3 @@ home-assistant.log*
 zigbee.db*
 *__pycache__*
 .ha_run.lock
-

esphome/owon-b35t-m5stack-core2.h

@@ -408,7 +408,8 @@ class Meter {
     std::string unit_line = std::string(this->scale()) + this->unit();
     it.print(270, 140, font, yellow, esphome::display::TextAlign::CENTER, unit_line.c_str());
 
-    this->draw_bargraph_(it, this->has_reading && !this->overload ? this->digits_from_buffer_() : 0, this->has_reading && !this->overload);
+    bool bargraph_active = this->connected && this->has_reading && !this->overload;
+    this->draw_bargraph_(it, bargraph_active ? this->digits_from_buffer_() : 0, bargraph_active);
     this->draw_icon_(it, 300, 148, 16, 16, DIODE_BMP, this->diode() ? magenta : inactive);
     this->draw_icon_(it, 300, 174, 16, 16, BUZZ_BMP, this->continuity() ? orange : inactive);