Switch

A clean, persistent on/off toggle. Use it when the action is binary and stays in its new state — lights on/off, fan on/off, an automation routine enabled or disabled.

[image] Switch on canvas, OFF state, Filled style

What it does

Switch holds a boolean state. The user flips it from the dashboard; your sketch reacts on the OFF→ON edge, on the ON→OFF edge, or whenever the state changes. Three visual styles: Flat, Outlined, Filled. Three sizes: S, M, L.

When to use it

• Light switch — Wire WHEN_TURNED_ON and WHEN_TURNED_OFF to a relay pin.
• Automation enable — WHEN_SWITCH_SET(isOn) flips a feature flag in your sketch.

Properties

The Inspector opens as a bottom sheet with a Widget ID field at the top, then these sections in order.

Widget ID

1. Essential

2. Header

3. Behavior

4. Appearance

5. Colors · ON state

6. Colors · OFF state

7. Colors · Disabled state

States and behavior

[image] Three states side by side: OFF, ON, Disabled

• OFF — OFF color set.
• ON — ON color set.
• Disabled — Disabled colors. Doesn’t react to taps.

The state is persistent across page navigation. In Server Mode, the state survives a server reboot (the server holds it).

In code

The switch mirrors what the user does on the dashboard. To react to it in your sketch:

ISwitch("kitchen_light") {
  WHEN_SWITCH_SET(isOn) {
    digitalWrite(RELAY_PIN, isOn ? HIGH : LOW);
  }
};

That’s the minimum — one event block, the new state arrives in isOn. You can also use WHEN_TURNED_ON and WHEN_TURNED_OFF separately if you only react to one edge. See InstantIoT Library / Receive Command from App for details.

Working Arduino code example

A complete sketch you can flash. The Widget ID kitchen_light matches the one you set on your Switch in the app.

[gif] Switch on the dashboard turning a relay on the ESP32 on and off

Direct Mode

Your phone connects directly to the ESP32’s SoftAP — no router, no server. Best for prototyping and standalone setups.

#include <InstantIoTWiFiAP.hpp>

const char* AP_SSID = "InstantIoT-Greenhouse";
const char* AP_PASS = "12345678";

#define RELAY_PIN 5

InstantIoTWiFiAP instant(AP_SSID, AP_PASS);

ISwitch("kitchen_light") {
  WHEN_SWITCH_SET(isOn) {
    digitalWrite(RELAY_PIN, isOn ? HIGH : LOW);
  }
};

void setup() {
  pinMode(RELAY_PIN, OUTPUT);
  digitalWrite(RELAY_PIN, LOW);
  instant.begin();
}

void loop() {
  instant.loop();
}

Server Mode

The ESP32 connects to your self-hosted InstantIoT Server over WiFi. Multiple devices, persistent state, history.

#include <InstantIoTWiFiServer.hpp>

const char*    WIFI_SSID     = "YOUR_WIFI_SSID";
const char*    WIFI_PASS     = "YOUR_WIFI_PASSWORD";
const char*    SERVER_IP     = "192.168.1.42";
const uint16_t SERVER_PORT   = 9001;
const char*    DEVICE_TOKEN  = "YOUR_DEVICE_TOKEN";

#define RELAY_PIN 5

InstantIoTWiFiServer instant(SERVER_IP, SERVER_PORT, DEVICE_TOKEN);

ISwitch("kitchen_light") {
  WHEN_SWITCH_SET(isOn) {
    digitalWrite(RELAY_PIN, isOn ? HIGH : LOW);
  }
};

void setup() {
  pinMode(RELAY_PIN, OUTPUT);
  digitalWrite(RELAY_PIN, LOW);
  instant.begin(WIFI_SSID, WIFI_PASS);
}

void loop() {
  instant.loop();
}

The widget code is identical — only the include and constructor change.

Notes

• The Colors · Disabled state section has only Track and Thumb — no Border or Label.

Next

→ Simple Button — When you want a momentary press instead of a held state.

→ Segmented Switch — When the choice is between 3+ options.