Segmented Switch

Presents two or more independently selectable options as labeled buttons or labeled buttons with icons and then updates the datastream with a numeric value corresponding to the index of the option selected by the user (index start is 0).

Datastream

Select or create a datastream of data type integer or enumerable.

Widget Controls

The widget has no controls other than buttons that allow the user to select the configured options.

How to process widget with the hardware

When button is pressed, value is sent and stored into the Blynk.Cloud. After that it's sent to your device.

Reading the widget value(s)

Example code:

BLYNK_WRITE {
  switch (param.asInt()) {
    case 0: { // Item 1
      Serial.println("Item 1 selected");
      break;
    }
    case 1: { // Item 2
      Serial.println("Item 2 selected");
      break;
    }    
  }
}

Changing the widget state

You can set the state of the widget by updating the assigned datastream value using the hardware or HTTP API.

Hardware:

For a datastream V5 assigned data type of integer or enumerable, the following will change the option selection to the second (index = 1):

Blynk.virtualWrite(V5, 1);

HTTP API:

https://{server_address}/external/api/update/?token={your 32 char token}&V5=1

Sketch: Basic Sketch

Sketch: Set Property

Sketch: VirtualPinWrite

Sketch: VirtualPinRead

Change Widget Properties

You can change certain properties of the Widget from your hardware. For that, use this command:

Blynk.setProperty(vPin, "widgetProperty", "propertyValue"); 

Where:

  • vPin is: virtual pin number the widget is assigned to

  • widgetProperty: property you want to change

  • propertyValue: value of the property you want to change

Don't put Blynk.setProperty()into the void loop() as it can cause a flood of messages and your hardware will be disconnected. Send such updates only when necessary, or use timers.

Properties you can change

You can change the properties labels, label, color, isDisabled, isHidden, and page of the widget from your hardware, or via an HTTP API. The URL must be encoded, so spaces in labels must be replaced with %20, and color hexadecimal values in the HTTP API URL must include the hash # character urlencoded as %23.

Change Option Labels

The labels property for the two or more widget options can be changed from the hardware with this command:

Blynk.setProperty(V1, "labels", "Unlocked", "Locked", "Reset");

The labels property can also be changed from HTTP API:

https://{server_address}/external/api/update/property?token={your 32 char token}&pin=V5&&labels=Unlocked&labels=Locked&labels=Reset

Change Widget Label

Blynk.setProperty(V1, "label", "Select");

Set Color

//#D3435C - Blynk RED 
Blynk.setProperty(V1, "color", "#D3435C");

Disable/Enable

Widget will be greyed out on UI and users won't be able to tap on it.

Blynk.setProperty(V1, "isDisabled", true);

Show/Hide

Widget will be hidden from dashboard. Design your UI so that it doesn't look weird when there is no widget.

Blynk.setProperty(V1, "isHidden", true);

Change widget properties via HTTPs API

Updates the Datastream Property and all assigned Widgets

GET https://{server_address}/external/api/update/property?token={your 32 char token}&pin={your vPin}&{property}={value}

The endpoint allows you to update the Datastream Property value via GET request. All widgets (both web and mobile) that are assigned to this datastream will inherit this property. The Datastream Property is persistent and will be stored forever until you change it with another value. In order to clear the property you need to clear the device data in device actions menu.

Example: https://blynk.cloud/external/api/update/property?token=GVki9IC70vb3IqvsV0YD3el4y0OpneL1&pin=V2&label=My%20Label

https://blynk.cloud/external/api/update/property?token=GVki9IC70vb3IqvsV0YD3el4y0OpneL1&pin=V1&color=%23D3435C

https://blynk.cloud/external/api/update/property?token=GVki9IC70vb3IqvsV0YD3el4y0OpneL1&pin=V1&isDisabled=true

Path Parameters

NameTypeDescription

{server address}*

string

Get from the bottom right of your Blynk console. More information.

Query Parameters

NameTypeDescription

token*

string

Device auth token from Device info

pin*

string

The datastream virtual pin (should start with "v")

{property}

string

The property of the widget you want to update: onLabel, offLabel, label, color, isDisabled, isHidden, and page

label

string

the text used as widget label

color

string

button color hexadecimal, must include the hash # character urlencoded as %23

isDisabled

string

true or false

isHidden

string

true or false

Sync to the latest known state

You can update your hardware to the latest datastream value from Blynk.Cloud after your hardware went offline, and then came online again. Use Blynk.syncVirtual() to update a single virtual pin, or Blynk.syncAll() to update all virtual pins. See State Syncing for more details.

BLYNK_CONNECTED() { 
  // Called when hardware is connected to Blynk.Cloud  

  // get the latest value for V1
  Blynk.syncVirtual(V1); 

  // Request Blynk server to re-send latest values for all pins
  Blynk.syncAll()
}

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