Django and chartjs using json (doesn't show chart) - javascript

I'm trying to display a chart in Django with data from database using JSON. When I go to /distancechart I see my data printed. But when it comes to chart I get blank screen, nothing shows. I was using some tutorials from internet and I have no idea what is wrong here...
views.py fragment
def distancechart(request):
labels = []
data = []
queryset = Distance.objects.values('day', 'distance')
for entry in queryset:
labels.append(entry['day'])
data.append(entry['distance'])
return JsonResponse(data={
'labels': labels,
'data': data,
})
distance.html
{% extends 'index.html' %}
{% block content %}
<canvas id="distancechart" width="1000" height="400"></canvas>
<script>
$.get('{% url "distancechart" %}', function(data) {
var ctx = $("#distancechart").get(0).getContext("2d");
new Chart(ctx, {
type: 'bar',
data: {
labels: data.labels,
datasets: [{
label: 'Distance',
data: data.data,
backgroundColor: [
'rgba(255, 99, 132, 0.2)',
'rgba(54, 162, 235, 0.2)',
'rgba(255, 206, 86, 0.2)',
'rgba(75, 192, 192, 0.2)',
'rgba(153, 102, 255, 0.2)',
'rgba(255, 159, 64, 0.2)'
],
borderColor: [
'rgba(255, 99, 132, 1)',
'rgba(54, 162, 235, 1)',
'rgba(255, 206, 86, 1)',
'rgba(75, 192, 192, 1)',
'rgba(153, 102, 255, 1)',
'rgba(255, 159, 64, 1)'
],
borderWidth: 1
}]
},
options: {
scales: {
yAxes: [{
ticks: {
beginAtZero: true
}
}]
}
}
});
});
</script>
{% endblock %}

Related

Bar Chart bars not showing up in Chart.js

Currently trying to create a bar chart in HTML/Javascript. Can't seem to get the bars showing for some reason. Below is the code and image..
Chart shows up but not the actual bars. Guessing this is a data issue but I've been stumped for ages. Any help is greatly appreciated!
HTML
<canvas id="myChart"></canvas>
JS
var ctx = document.getElementById('myChart').getContext('2d');
var myChart = new Chart(ctx, {
type: 'bar',
data: {
label: ['Red','Blue','Yellow','Green','Purple','Orange'],
datasets: [{
label: 'number of votes',
data: [1,2,3,4,5,6],
backgroundColor: [
'rgba(255, 99, 132, 0.2)',
'rgba(54, 162, 235, 0.2)',
'rgba(255, 206, 86, 0.2)',
'rgba(75, 192, 192, 0.2)',
'rgba(153, 102, 255, 0.2)',
'rgba(255, 159, 64, 0.2)'
],
borderColor: [
'rgba(255, 99, 132, 0.2)',
'rgba(54, 162, 235, 0.2)',
'rgba(255, 206, 86, 0.2)',
'rgba(75, 192, 192, 0.2)',
'rgba(153, 102, 255, 0.2)',
'rgba(255, 159, 64, 0.2)'
],
borderWidth: 1
}]
},
options: {
scales: {
y: {
beginAtZero: true
}
}
}
});

You have to use labels instead of label for the bar labels. See the official documentation: LINK
So your JS would look like this (see the change on line 5):
var ctx = document.getElementById('myChart').getContext('2d');
var myChart = new Chart(ctx, {
type: 'bar',
data: {
labels: ['Red','Blue','Yellow','Green','Purple','Orange'],
datasets: [{
label: 'number of votes',
data: [1,2,3,4,5,6],
backgroundColor: [
'rgba(255, 99, 132, 0.2)',
'rgba(54, 162, 235, 0.2)',
'rgba(255, 206, 86, 0.2)',
'rgba(75, 192, 192, 0.2)',
'rgba(153, 102, 255, 0.2)',
'rgba(255, 159, 64, 0.2)'
],
borderColor: [
'rgba(255, 99, 132, 0.2)',
'rgba(54, 162, 235, 0.2)',
'rgba(255, 206, 86, 0.2)',
'rgba(75, 192, 192, 0.2)',
'rgba(153, 102, 255, 0.2)',
'rgba(255, 159, 64, 0.2)'
],
borderWidth: 1
}]
},
options: {
scales: {
y: {
beginAtZero: true
}
}
}
});

It is a basic typo error. It should be 'labels' whereas you have written 'label'.
data: {
labels: ['Red','Blue','Yellow','Green','Purple','Orange'],
datasets: [{

Django - Chart.js doesn't return nothing

I'm new on js and i'm trying to build something simple. I've no error in the console but chart doesn't display on my Django website.
If someone can help me, please, would be great.
{% extends 'account/main.html' %}
<script>
{% block jquery %}
var endpoint = '/api/chart/data/'
var defaultData = []
var labels = [];
$.ajax({
method: "GET",
url: endpoint,
success: function(data){
labels = data.labels
defaultData = data.default
setChart()
},
error: function(error_data){
console.log("error")
console.log(error_data)
}
})
function setChart(){
var ctx = document.getElementById("myChart");
var ctx2 = document.getElementById("myChart2");
var myChart = new Chart(ctx2, {
type: 'bar',
data: {
labels: labels,
datasets: [{
label: '# of Votes',
data: defaultData,
backgroundColor: [
'rgba(255, 99, 132, 0.2)',
'rgba(54, 162, 235, 0.2)',
'rgba(255, 206, 86, 0.2)',
'rgba(75, 192, 192, 0.2)',
'rgba(153, 102, 255, 0.2)',
'rgba(255, 159, 64, 0.2)'
],
borderColor: [
'rgba(255,99,132,1)',
'rgba(54, 162, 235, 1)',
'rgba(255, 206, 86, 1)',
'rgba(75, 192, 192, 1)',
'rgba(153, 102, 255, 1)',
'rgba(255, 159, 64, 1)'
],
borderWidth: 1
}]
},
options: {
scales: {
yAxes: [{
ticks: {
beginAtZero:true
}
}]
}
}
});
var myChart = new Chart(ctx, {
type: 'polarArea',
data: {
labels: labels,
datasets: [{
label: '# of Votes',
data: defaultData,
backgroundColor: [
'rgba(255, 99, 132, 0.2)',
'rgba(54, 162, 235, 0.2)',
'rgba(255, 206, 86, 0.2)',
'rgba(75, 192, 192, 0.2)',
'rgba(153, 102, 255, 0.2)',
'rgba(255, 159, 64, 0.2)'
],
borderColor: [
'rgba(255,99,132,1)',
'rgba(54, 162, 235, 1)',
'rgba(255, 206, 86, 1)',
'rgba(75, 192, 192, 1)',
'rgba(153, 102, 255, 1)',
'rgba(255, 159, 64, 1)'
],
borderWidth: 1
}]
},
options: {
scales: {
yAxes: [{
ticks: {
beginAtZero:true
}
}]
}
}
});
}
// var ctx = document.getElementById("myChart");
{% endblock %}
</script>
{% block content %}
<head>
<title>Home</title>
</head>
<body>
<canvas id="myChart" width="400" height="400"></canvas>
<form method="GET" action="" name="myform" value="home" id="subform">
{% csrf_token %}
</form>

Missing colors in my Chart.js, my data looks fine, but no color

I made my first bar with Chart.js library.
My data looks nice, but I can't give my valuest some color.
enter image description here
My function looks like this:
var $barData =
{
type: 'bar',
labels: ['Super mad', 'Middel', 'Ikke ok', 'Gennemsnit'],
datasets:
[
{
label: 'Antal stemmer',
data: [
[$arrStemmer[0]],
[$arrStemmer[1]],
[$arrStemmer[2]],
[$Snit_Vaerdi]
],
backgroundColor: [
'rgba(255, 99, 132, 0.2)',
'rgba(54, 162, 235, 0.2)',
'rgba(255, 206, 86, 0.2)',
'rgba(75, 192, 192, 0.2)'
],
borderColor: [
'rgba(255, 99, 132, 1)',
'rgba(54, 162, 235, 1)',
'rgba(255, 206, 86, 1)',
'rgba(75, 192, 192, 1)'
],
borderWidth: 1
}
]
}
// Hent graf initialiserings setup
var $Stemmer = document.getElementById("can_afstemning_graf").getContext("2d");
// Tegn graf, men data fra barData objektet
new Chart($Stemmer).Bar($barData);
What am I missing?
I am looking here in the documentation and it look fine: https://www.chartjs.org/docs/latest/.
Thanks,
Nenad

You are setting the data incorrectly.
You should use
data: [
$arrStemmer[0],
$arrStemmer[1],
$arrStemmer[2],
$Snit_Vaerdi
],
Instead of
data: [
[$arrStemmer[0]],
[$arrStemmer[1]],
[$arrStemmer[2]],
[$Snit_Vaerdi]
],

This should work. if the $arrStemmer and $snit_Vaerdi are filled.
let $stemmer = document.getElementById('can_afstemning_graf').getContext('2d');
let myChart = new Chart($stemmer, {
type: 'bar',
data: {
labels: ['Super mad', 'Middel', 'Ikke ok', 'Gennemsnit'],
datasets: [{
label: 'Antal stemmer',
data: [
$arrStemmer[0],
$arrStemmer[1],
$arrStemmer[2],
$Snit_Vaerdi
],
backgroundColor: [
'rgba(255, 99, 132, 0.2)',
'rgba(54, 162, 235, 0.2)',
'rgba(255, 206, 86, 0.2)',
'rgba(75, 192, 192, 0.2)'
],
borderColor: [
'rgba(255, 99, 132, 1)',
'rgba(54, 162, 235, 1)',
'rgba(255, 206, 86, 1)',
'rgba(75, 192, 192, 1)'
],
borderWidth: 1
}]
},
options: {
scales: {
yAxes: [{
ticks: {
beginAtZero: true
}
}]
}
}
});

Integrate chart.js with single javascript file

I am implementing an application with codeigniter framework, I want to produce charts with Chart.JS, I have a controller an array with the data and I intend to send them to the javascript file with the graph implementation, and show everything in the view, but I can not pass the data.
Controller
function index() {
$data['DT'] = $this->Dashboard_main_model->get_dt_in();
$data['CL'] = $this->Dashboard_main_model->get_cl_in();
$data['MT'] = $this->Dashboard_main_model->get_mt_in();
$data['SN_AU'] = $this->Dashboard_main_model->get_sn_au_in();
$data['SN_AT'] = $this->Dashboard_main_model->get_sn_at_in();
$data['SN_MR'] = $this->Dashboard_main_model->get_sn_mr_in();
$data['DT_TMPs'] = $this->Dashboard_main_model->get_dt_tmp_in();
$data['CL_TMPs'] = $this->Dashboard_main_model->get_cl_tmp_in();
$data['_view'] = 'dashboard';
$this->load->view('layouts/main', $data);
}
JS FILE teste.js
var ctx = document.getElementById('myChart').getContext('2d');
var myChart = new Chart(ctx, {
type: 'bar',
data: {
labels: ['Red', 'Blue', 'Yellow', 'Green', 'Purple', 'Orange'],
datasets: [{
label: '# of Votes',
data: [12, 19, 3, 5, 2, 3],
backgroundColor: [
'rgba(255, 99, 132, 0.2)',
'rgba(54, 162, 235, 0.2)',
'rgba(255, 206, 86, 0.2)',
'rgba(75, 192, 192, 0.2)',
'rgba(153, 102, 255, 0.2)',
'rgba(255, 159, 64, 0.2)'
],
borderColor: [
'rgba(255, 99, 132, 1)',
'rgba(54, 162, 235, 1)',
'rgba(255, 206, 86, 1)',
'rgba(75, 192, 192, 1)',
'rgba(153, 102, 255, 1)',
'rgba(255, 159, 64, 1)'
],
borderWidth: 1
}]
},
options: {
scales: {
yAxes: [{
ticks: {
beginAtZero: true
}
}]
}
}
});
view
<div class="col-md-6">
<div class="box">
<div class="box-header">
<h3 class="box-title">Chamadas Atendidas</h3>
</div>
<div class="box-body no-padding">
<canvas id="myChart" style="auto;"></canvas>
</div>
</div>
</div>
</div>

Well I had a go at this and it seems the best bet is to install the Chart.min.js locally on your server - I grabbed it from Github - the link is on the chartjs.org site ( which you have obviously been to already)
Download it and save it where appropriate for your setup.
Controller - Chart.php
<?php
defined('BASEPATH') OR exit('No direct script access allowed');
class Chart extends CI_Controller {
public function __construct() {
parent::__construct();
}
public function index() {
$this->load->helper('url');
$this->load->view('chart_view');
}
}
View - chart_view.php
<canvas id="myChart"></canvas>
// Load the Chart.min.js locally on the server
// Note: make sure you have application/config/config.php config['base_url'] correctly set.
<script src="<?=base_url('assets/chart/2.8.0/Chart.min.js');?>"></script>
<script type="application/javascript">
let ctx = document.getElementById('myChart').getContext('2d');
let myChart = new Chart(ctx, {
type: 'bar',
data: {
labels: ['Red', 'Blue', 'Yellow', 'Green', 'Purple', 'Orange'],
datasets: [{
label: '# of Votes',
data: [12, 19, 3, 5, 2, 3],
backgroundColor: [
'rgba(255, 99, 132, 0.2)',
'rgba(54, 162, 235, 0.2)',
'rgba(255, 206, 86, 0.2)',
'rgba(75, 192, 192, 0.2)',
'rgba(153, 102, 255, 0.2)',
'rgba(255, 159, 64, 0.2)'
],
borderColor: [
'rgba(255, 99, 132, 1)',
'rgba(54, 162, 235, 1)',
'rgba(255, 206, 86, 1)',
'rgba(75, 192, 192, 1)',
'rgba(153, 102, 255, 1)',
'rgba(255, 159, 64, 1)'
],
borderWidth: 1
}]
},
options: {
scales: {
yAxes: [{
ticks: {
beginAtZero: true
}
}]
}
}
});
</script>
And I got a nice little chart showing up.
See if that works for you.

Displaying data from simple html form to display in chartjs

I am trying to create a simple form to collect input from the user then display the user data in a bar chart using chartjs. Below is my current javascript code. I want the testValue1, testValue2, testValue3 and testValue4 to display as my data. Any help on what I am missing would be greatly appreciated.
function displayGraph () {
let testOutput = document.getElementById("welcome");
let testValue1 = document.getElementById("test1");
let testValue2 = document.getElementById("test2");
let testValue3 = document.getElementById("test3");
let testValue4 = document.getElementById("test4");
}
let barChart = new Chart(rateOfReturn, {
type: 'bar',
data: {
labels: ["Rate of Return", "Fee #1", "Fee #2", "Fee #3"],
datasets: [{
label: 'Balance by Year',
data: [],
backgroundColor: [
'rgba(255, 99, 132, 0.2)',
'rgba(54, 162, 235, 0.2)',
'rgba(255, 206, 86, 0.2)',
'rgba(75, 192, 192, 0.2)',
'rgba(153, 102, 255, 0.2)',
'rgba(255, 159, 64, 0.2)'
],
borderColor: [
'rgba(255,99,132,1)',
'rgba(54, 162, 235, 1)',
'rgba(255, 206, 86, 1)',
'rgba(75, 192, 192, 1)',
'rgba(153, 102, 255, 1)',
'rgba(255, 159, 64, 1)'
],
borderWidth: 1
}]
},
});

I am not sure your implementation. If you trying to get a value from an input into a chart. Won't something like this work?
<canvas id="myChart" width="400" height="400"></canvas>
<script>
var ctx = document.getElementById("myChart").getContext('2d');
var testOutput = document.getElementById("welcome").value;
var testValue1 = document.getElementById("test1").value;
var testValue2 = document.getElementById("test2").value;
var testValue3 = document.getElementById("test3").value;
var testValue4 = document.getElementById("test4").value;
var myChart = new Chart(ctx, {
type: 'bar',
data: {
labels: ["Red", "Blue", "Yellow", "Green", "Purple", "Orange"],
datasets: [{
label: '# of Votes',
data: [testValue1, testValue2, testValue3, testValue4],
backgroundColor: [
'rgba(255, 99, 132, 0.2)',
'rgba(54, 162, 235, 0.2)',
'rgba(255, 206, 86, 0.2)',
'rgba(75, 192, 192, 0.2)',
'rgba(153, 102, 255, 0.2)',
'rgba(255, 159, 64, 0.2)'
],
borderColor: [
'rgba(255,99,132,1)',
'rgba(54, 162, 235, 1)',
'rgba(255, 206, 86, 1)',
'rgba(75, 192, 192, 1)',
'rgba(153, 102, 255, 1)',
'rgba(255, 159, 64, 1)'
],
borderWidth: 1
}]
},
options: {
scales: {
yAxes: [{
ticks: {
beginAtZero:true
}
}]
}
}
});
</script>
Reference: http://www.chartjs.org/docs/latest/

Maybe you can pass data instead of the empty array
datasets: [{
label: 'Balance by Year',
data: [], // Empty Array
backgroundColor: [
'rgba(255, 99, 132, 0.2)',
'rgba(54, 162, 235, 0.2)',
'rgba(255, 206, 86, 0.2)',
'rgba(75, 192, 192, 0.2)',
'rgba(153, 102, 255, 0.2)',
'rgba(255, 159, 64, 0.2)'
],
borderColor: [
'rgba(255,99,132,1)',
'rgba(54, 162, 235, 1)',
'rgba(255, 206, 86, 1)',
'rgba(75, 192, 192, 1)',
'rgba(153, 102, 255, 1)',
'rgba(255, 159, 64, 1)'
],
borderWidth: 1
}]
You can first follow the latest Bar chart example and then reproduce it for yourself. http://www.chartjs.org/docs/latest/charts/bar.html

Here you go. This works.
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<meta http-equiv="X-UA-Compatible" content="ie=edge">
<title>SimpleAdd</title>
<script src="https://cdnjs.cloudflare.com/ajax/libs/Chart.js/2.7.3/Chart.min.js" charset="utf-8"></script>
</head>
<body>
<form>
Test:<br>
<input id="test1" type="text">
<input type="button" value="Add data" onclick="adddata()">
</form>
<canvas id="myChart"></canvas>
<script type="text/javascript">
var ctx = document.getElementById("myChart").getContext('2d');
function adddata() {
let test1 = document.getElementById("test1").value;
// myChart.data.labels[1] = testName1;
myChart.data.datasets[0].data[0] = test1;
myChart.update();
}
var myChart = new Chart(ctx, {
type: 'bar',
data: {
labels: ["Red"],
datasets: [{
label: '# of Votes',
data: [test1],
backgroundColor: [
'rgba(255, 99, 132, 0.2)'
],
borderColor: [
'rgba(255,99,132,1)'
],
borderWidth: 1
}]
},
options: {
scales: {
yAxes: [{
ticks: {
beginAtZero: true
}
}]
}
}
});
</script>
</body>
</html>

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