test.php

<meta name="viewport" content="width=device-width, initial-scale=1">
<style>
* {box-sizing: border-box}
body {font-family: Verdana, sans-serif; margin:0}
.mySlides {display: none}
img {vertical-align: middle;}

/* Slideshow container */
.slideshow-container {
  max-width: 1000px;
  position: relative;
  margin: auto;
}

/* Next & previous buttons */
.prev, .next {
  cursor: pointer;
  position: absolute;
  top: 50%;
  width: auto;
  padding: 16px;
  margin-top: -22px;
  color: white;
  font-weight: bold;
  font-size: 18px;
  transition: 0.6s ease;
  border-radius: 0 3px 3px 0;
  user-select: none;
}

/* Position the "next button" to the right */
.next {
  right: 0;
  border-radius: 3px 0 0 3px;
}

/* On hover, add a black background color with a little bit see-through */
.prev:hover, .next:hover {
  background-color: rgba(0,0,0,0.8);
}

/* Caption text */
.text {
  color: #f2f2f2;
  font-size: 15px;
  padding: 8px 12px;
  position: absolute;
  bottom: 8px;
  width: 100%;
  text-align: center;
}

/* Number text (1/3 etc) */
.numbertext {
  color: #f2f2f2;
  font-size: 12px;
  padding: 8px 12px;
  position: absolute;
  top: 0;
}

/* The dots/bullets/indicators */
.dot {
  cursor: pointer;
  height: 15px;
  width: 15px;
  margin: 0 2px;
  background-color: #bbb;
  border-radius: 50%;
  display: inline-block;
  transition: background-color 0.6s ease;
}

.active, .dot:hover {
  background-color: #717171;
}

/* Fading animation */
.fade {
  -webkit-animation-name: fade;
  -webkit-animation-duration: 1.5s;
  animation-name: fade;
  animation-duration: 1.5s;
}

@-webkit-keyframes fade {
  from {opacity: .4} 
  to {opacity: 1}
}

@keyframes fade {
  from {opacity: .4} 
  to {opacity: 1}
}

/* On smaller screens, decrease text size */
@media only screen and (max-width: 300px) {
  .prev, .next,.text {font-size: 11px}
}
</style>
<div class="slideshow-container">

<div class="mySlides fade">
  <div class="numbertext">1 / 3</div>
  <img src="img_nature_wide.jpg" style="width:100%">
  <div class="text">Caption Text</div>
</div>

<div class="mySlides fade">
  <div class="numbertext">2 / 3</div>
  <img src="img_snow_wide.jpg" style="width:100%">
  <div class="text">Caption Two</div>
</div>

<div class="mySlides fade">
  <div class="numbertext">3 / 3</div>
  <img src="img_mountains_wide.jpg" style="width:100%">
  <div class="text">Caption Three</div>
</div>

<a class="prev" onclick="plusSlides(-1)">&#10094;</a>
<a class="next" onclick="plusSlides(1)">&#10095;</a>

</div>
<br>

<div style="text-align:center">
  <span class="dot" onclick="currentSlide(1)"></span> 
  <span class="dot" onclick="currentSlide(2)"></span> 
  <span class="dot" onclick="currentSlide(3)"></span> 
</div>



<div id="chartContainer2" style="height: 400px; width: 100%;"></div>
<br/><br/><br/><br/>
<div id="chartContainer3" style="height: 400px; width: 100%;"></div>
 <script src="https://canvasjs.com/assets/script/canvasjs.min.js"></script>
 <script>
function chart(chartId = "chartContainer1", _data, nameChart) {
	console.log(_data)
points = [];
	_data.forEach(function(entry) {
		new_arr = [];
	entry['chart'].forEach(function(i) {
		new_arr.push({
	label : i['x'],
	y : parseInt(i['y'])
	});
});
points.push({
	type: "spline",
		name: entry['index'],
		showInLegend: true,
	dataPoints : new_arr
});
});
console.log(points)
var chart = new CanvasJS.Chart(chartId, {
	theme:"light2",
	animationEnabled: true,
	title:{
		text: nameChart
	},
	axisY :{
		includeZero: false,
		title: "Moisture Values",
	},
	legend:{
		cursor:"pointer",
		itemclick : toggleDataSeries
	},
	toolTip: {
		shared: true
	},
	data:points
});
chart.render();
}

function toggleDataSeries(e) {
	if (typeof(e.dataSeries.visible) === "undefined" || e.dataSeries.visible ){
		e.dataSeries.visible = false;
	} else {
		e.dataSeries.visible = true;
	}
	chart.render();
}

var slideIndex = 1;
showSlides(slideIndex);

function plusSlides(n) {
  showSlides(slideIndex += n);
}

function currentSlide(n) {
  showSlides(slideIndex = n);
}

function showSlides(n) {
  var i;
  var slides = document.getElementsByClassName("mySlides");
  var dots = document.getElementsByClassName("dot");
  if (n > slides.length) {slideIndex = 1}    
  if (n < 1) {slideIndex = slides.length}
  for (i = 0; i < slides.length; i++) {
      slides[i].style.display = "none";  
  }
  for (i = 0; i < dots.length; i++) {
      dots[i].className = dots[i].className.replace(" active", "");
  }
  slides[slideIndex-1].style.display = "block";  
  dots[slideIndex-1].className += " active";
}
</script>
<?php
//select individual_sensor.Sensor_Index from individual_sensor where individual_sensor.Sensor_ID = 'SEN0169'
$sensor_arr = ['SEN0169', 'SEN0114', 'SEN0193'];
$response = array();
// include db_connect
$filepath = realpath(dirname(__FILE__));
require_once $filepath . "/db_connect.php";

// establish connection to db
$db = new DB_CONNECT();

foreach ($sensor_arr as $item) {
    // SQL query to insert Data to table
    if ($db->connect()) {
        $query_str = "select Individual_Sensor.Sensor_Index from Individual_Sensor where Individual_Sensor.Sensor_ID = '" . $item . "'";
        $result = $db->query($query_str);
		$chart = [];
        while ($row = $result->fetch_assoc() ) {
            $query_str = "select distinct Data.Time as x, Data.Sensor_Reading as y from Individual_Sensor, Data
				where Individual_Sensor.Sensor_ID = '" . $item . "' and Data.Sensor_Index = " . $row["Sensor_Index"] . " and Individual_Sensor.Sensor_Index = Data.Sensor_Index
				order by Individual_Sensor.Sensor_Index asc";
            $result2 = $db->query($query_str);
            $new_array = [];
            while ($row2 = $result2->fetch_assoc()) {
                $n = $row2['y'];
                $new_array[] = $row2;
            }
            $chart[] = ['index' => $row["Sensor_Index"], 'chart' => $new_array];
        }
        #if ($item == 'SEN0169') {
        #    echo '<script type="text/javascript">
        #                    chart("chartContainer1", ' . json_encode($chart) . ', "SEN0169");
        #				</script>';
        #}
        if ($item == 'SEN0114') {
            echo '<script type="text/javascript">
								chart("chartContainer2", ' . json_encode($chart) . ',"SEN0114");
						</script>';
        } else if ($item == 'SEN0193') {
            echo '<script type="text/javascript">
									chart("chartContainer3", ' . json_encode($chart) . ', "SEN0193");
							1</script>';
        }
    }
}
$db->close();

?>