Mirroring PR #537

lib/hal/HalGPIO.h

@@ -54,3 +54,5 @@ class HalGPIO {
   static constexpr uint8_t BTN_DOWN = 5;
   static constexpr uint8_t BTN_POWER = 6;
 };
+
+extern HalGPIO gpio;  // Singleton

src/components/themes/BaseTheme.cpp

@@ -34,13 +34,36 @@ void drawBatteryIcon(const GfxRenderer& renderer, int x, int y, int battWidth, i
   renderer.drawPixel(x + battWidth - 1, y + rectHeight - 4);
   renderer.drawLine(x + battWidth - 0, y + 4, x + battWidth - 0, y + rectHeight - 5);
 
+  const bool charging = gpio.isUsbConnected();
+
   // The +1 is to round up, so that we always fill at least one pixel
-  int filledWidth = percentage * (battWidth - 5) / 100 + 1;
-  if (filledWidth > battWidth - 5) {
-    filledWidth = battWidth - 5;  // Ensure we don't overflow
+  constexpr int maxFillWidth = battWidth - 5;
+  int filledWidth = percentage * maxFillWidth / 100 + 1;
+  if (filledWidth > maxFillWidth) {
+    filledWidth = maxFillWidth;
+  }
+
+  // When charging, ensure minimum fill so lightning bolt is fully visible
+  constexpr int minFillForBolt = 8;
+  if (charging && filledWidth < minFillForBolt) {
+    filledWidth = minFillForBolt;
   }
 
   renderer.fillRect(x + 2, y + 2, filledWidth, rectHeight - 4);
+
+  // Draw lightning bolt when charging (white/inverted on black fill for visibility)
+  if (charging) {
+    const int boltX = x + 4;
+    const int boltY = y + 2;
+    renderer.drawLine(boltX + 4, boltY + 0, boltX + 5, boltY + 0, false);
+    renderer.drawLine(boltX + 3, boltY + 1, boltX + 4, boltY + 1, false);
+    renderer.drawLine(boltX + 2, boltY + 2, boltX + 5, boltY + 2, false);
+    renderer.drawLine(boltX + 3, boltY + 3, boltX + 4, boltY + 3, false);
+    renderer.drawLine(boltX + 2, boltY + 4, boltX + 3, boltY + 4, false);
+    renderer.drawLine(boltX + 1, boltY + 5, boltX + 4, boltY + 5, false);
+    renderer.drawLine(boltX + 2, boltY + 6, boltX + 3, boltY + 6, false);
+    renderer.drawLine(boltX + 1, boltY + 7, boltX + 2, boltY + 7, false);
+  }
 }
 }  // namespace