Handle button presses

client/client.ino

@@ -61,8 +61,12 @@ Adafruit_ST7735 display(TFT_CS, TFT_DC, TFT_RESET);
 
 class State {
 public:
-  virtual void enter() = 0;
-  virtual void tick() = 0;
+  // When the state is entered
+  virtual void enter();
+  // Called in the business loop
+  virtual void tick();
+  // Called when the button is pushed
+  virtual void button();
   virtual ~State() = default;
 };
 
@@ -75,7 +79,6 @@ public:
 class StateFetching : public State {
 public:
   void enter() override;
-  void tick() override;
 };
 
 class StateShowingDepartures : public State {
@@ -87,8 +90,15 @@ public:
   StateShowingDepartures(String&);
   void enter() override;
   void tick() override;
+  void button() override;
 };
 
+// Empty default implementations
+
+void State::enter() {}
+void State::tick() {}
+void State::button() {}
+
 // App state implementation
 
 uint64_t currentTick = 0;
@@ -143,9 +153,6 @@ void StateFetching::enter() {
   setState<StateShowingDepartures>(departuresRaw);
 };
 
-void StateFetching::tick() {
-}
-
 StateShowingDepartures::StateShowingDepartures(String &departuresRaw) {
   deserializeJson(departures, departuresRaw);
 }
@@ -154,9 +161,11 @@ void StateShowingDepartures::enter() {
   Serial.println("Entering StateShowingDepartures");
   entered = millis();
 
+  // clear status and main areas
   display.fillRect(STATUS_X, STATUS_Y, STATUS_WIDTH, STATUS_HEIGHT, COLOR_BG);
   display.fillRect(MAIN_X, MAIN_Y, MAIN_WIDTH, MAIN_HEIGHT, COLOR_BG);
 
+  // draw timetable
   int line = 0;
   for (JsonVariant departure : departures["departures"].as<JsonArray>()) {
     display.setCursor(MAIN_X, MAIN_Y + (CY + 3) * line);
@@ -183,6 +192,10 @@ void StateShowingDepartures::tick() {
   }
 }
 
+void StateShowingDepartures::button() {
+  setState<StateFetching>();
+}
+
 int buttonPushed = false;
 
 void ICACHE_RAM_ATTR onButtonFalling() {
@@ -218,6 +231,9 @@ void loop() {
     stateChanged = false;
     // Note: enter() may call setState(). In that case we want to end up right back here.
     state->enter();
+  } else if (buttonPushed) {
+    buttonPushed = false;
+    state->button();
   } else {
     state->tick();
     currentTick++;