Multi Select Helper Example¶

/**
 * SPDX-FileCopyrightText: 2026 Maximiliano Ramirez <maximiliano.ramirezbravo@gmail.com>
 *
 * SPDX-License-Identifier: MIT
 */

/**
 * ReactiveESP32 Example Overview:
 * - This example demonstrates the usage of the MultiSelectHelper to select between multiple signals
 *   based on a selector signal.
 * - The library has +30 built-in helpers, and users can define custom helpers for common patterns
 *   (see documentation for more details).
 * - An enum class 'Options' is defined to represent four selectable options.
 * - A Signal<Options> named 'selector' holds the current selected option.
 * - Four Signal<uint8_t> signals represent the values for each option.
 *
 * - The Serial interface is used to interact with the program:
 *   - 'g': Get the current selected option value.
 *   - '1': Set selector to Option1.
 *   - '2': Set selector to Option2.
 *   - '3': Set selector to Option3.
 *   - '4': Set selector to Option4.
 *
 * - Pressing '0' restarts the ESP32.
 */

#include <ReactiveESP32.h>
using namespace RxESP32;

/* ---------------------------------------------------------------------------------------------- */
// Define an enum class to represent a selection of options
enum class Options : uint8_t {
  Option1 = 0,
  Option2,
  Option3,
  Option4,
};

// Define a Signal to hold the current selection using the Options enum
Signal<Options> selector(Options::Option1);

// Define signals to represent whether each option is selected
Signal<uint8_t> is_option1_selected(1);
Signal<uint8_t> is_option2_selected(2);
Signal<uint8_t> is_option3_selected(3);
Signal<uint8_t> is_option4_selected(4);

// Use the multiSelect() helper to link the selector signal to the individual option signals
// The helper creates a computed with the value of the selected option signal
auto selected_option = Helpers::Combinatorial::multiSelect(selector, is_option1_selected,
  is_option2_selected, is_option3_selected, is_option4_selected);

// Effect that prints whenever the selected option changes
Effect<> print_effect([]() {
  uint8_t value = selected_option.get();
  Serial.printf("\tEffect: Selected Option Value: %u\n", value);
  return nullptr; // No cleanup needed
});

// Read Serial input and process commands
void serialRead();
/* ---------------------------------------------------------------------------------------------- */

void setup() {
  Serial.begin(115200);
  delay(1000);

  Serial.println("=========================================");
  Serial.println("ReactiveESP32 - MultiSelectHelper Example");
  Serial.println("=========================================");

  // Start the ReactiveESP32 dispatcher
  if (!Dispatcher::start()) {
    Serial.println("Failed to start ReactiveESP32 Dispatcher!");
    while (true) {
      delay(1000);
    }
  }
}

void loop() { serialRead(); }

void serialRead() {
  if (!Serial.available()) return;

  char c = Serial.read();

  if (c == '\r') return;
  if (c == '\n') c = ' ';
  Serial.printf("> %c\n", c);

  switch (c) {
    case '0':
    {
      // Restart the ESP32
      ESP.restart();
    } break;

    case 'g':
    {
      // Get the current selected option value
      uint8_t value = selected_option.get();
      Serial.printf("Selected Option Value: %u\n", value);
    } break;

    case '1':
    {
      // Set selector to Option1
      selector.set(Options::Option1);
      Serial.println("Selector set to Option1");
    } break;

    case '2':
    {
      // Set selector to Option2
      selector.set(Options::Option2);
      Serial.println("Selector set to Option2");
    } break;

    case '3':
    {
      // Set selector to Option3
      selector.set(Options::Option3);
      Serial.println("Selector set to Option3");
    } break;

    case '4':
    {
      // Set selector to Option4
      selector.set(Options::Option4);
      Serial.println("Selector set to Option4");
    } break;
  }
}