Joystick
This widget allows you to control something in four directions, such as a pair of servos or electric motors.
For both modes, the joystick will update the datastream(s) with the minimum X to the left, the maximum X to the right, the minimum Y to the bottom, and the maximum Y to the top.
Simple - Assign one datastream each to the X and Y directions of data type integer or double. The output from the joystick movement will vary between the datastream min and max values.
Advanced - Assign one datastream of data type string. In the hardware, you access the X and Y direction values from the datastream. The X and Y values will vary between 0 and 255.
The widget has one control, the joystick. Press and then slide the joystick radially from the center position to change the X and Y direction outputs.
The same settings apply to both modes of Simple and Advanced.
- Autoreturn - when enabled, the joystick will return to the center position after it is released by the user.
- Rotate on tilt - when enabled, the output from the joystick will keep the X and Y directions aligned relative to the smartphone screen orientation (portrait / landscape).
When the joystick is pressed and moved, the value is sent and stored into the Blynk.Cloud. After that it's sent to your hardware.
Simple Mode
BLYNK_WRITE(V4) {
// Called when virtual pin V4 is updated by
// Blynk.App joystick widget.
int x = param.asInt(); // For datastream of data type integer
//double x = param.asDouble(); // For datastream of data type double
Serial.print("V4: x =");
Serial.println(x);
} // BLYNK_WRITE(V4)
BLYNK_WRITE(V5) {
// Called when virtual pin V5 is updated by
// Blynk.App joystick widget.
int y = param.asInt(); // For datastream of data type integer
//double y = param.asDouble(); // For datastream of data type double
Serial.print("V5: y =");
Serial.println(y);
} // BLYNK_WRITE(V5)
Advanced Mode
BLYNK_WRITE(V2) {
// Called when virtual pin V2 is updated from the Blynk.App
// V2 is a datastream of data type String assigned to a
// Blynk.App joystick widget.
int x = param[0].asInt();
int y = param[1].asInt();
Serial.print("V2: x = ");
Serial.print(x);
Serial.print("\t y=");
Serial.println(y);
} // BLYNK_WRITE(V2)
You can also change the datastream value with the hardware, resulting in a change to the widgets assigned to that datastream.
Simple Mode
If V1 and V2 are datastreams of data type integer with the minimum value set to 0 and the maximum set to 255, and V1 is assigned to the joystick X direction, and V2 is assigned to the joystick Y direction, then the following code will move the joystick to the left and upward:
Blynk.virtualWrite(V1, 0);
Blynk.virtualWrite(V2, 255);
Advanced Mode
If V3 is a datastream of data type string, then the following code will move the joystick to the left and upward position:
Blynk.virtualWrite(V3, 0, 255);
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 towidgetProperty
: property you want to changepropertyValue
: 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.You can change the properties “label”, “color”, “isDisabled” and “isHidden” 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.
Blynk.setProperty(V1, "label", "Toggle");
//#D3435C - Blynk RED
Blynk.setProperty(V1, "color", "#D3435C");
Widget will be greyed out on UI and users won't be able to tap on it.
Blynk.setProperty(V1, "isDisabled", true);
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);
get
https://{server_address}
/external/api/update/property?token={your 32 char token}&pin={your vPin}&{property}={value}
Updates the Datastream Property and all assigned Widgets
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()
}
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.Last modified 3mo ago