​

function setup() {

  createCanvas(400, 400);

    x = 50

    y = height / 2

}

​

function draw() {

  //the line the slider glides on

  background(220); 

  strokeWeight(7);

 line(50,200, 350,200);

  //the slider thingy

  rectMode(CENTER);

  rect(x, y, 28, 50);

    print(mouseX, mouseY);

  //slider functionality

   if (mouseIsPressed) {

    x = mouseX;

     //make it stay on the slider

​

    if (mouseX < 50) {

      x = 50

    }

    if (mouseX > 350) {

      x = 350

    }

  }

}