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Chart JS annotation issues

I am trying to load annotation the dynamic chart that I create after receiving data from the database and I have tried all possible options but somehow the chart loads but no the annotations.
chart.js version = v2.9.4
chart-plugin-annotation.min.js version = 0.5.7
Function in JS that runs when data is receiving from db:
function DrawChart(timeLabelList, unitsProducedList, goalList){
if(draw_the_chart != null) draw_the_chart.destroy();
Chart.defaults.global.defaultFontColor = 'white';
var ctx = document.getElementById('draw_the_chart').getContext("2d");
draw_the_chart = new Chart(ctx, {
type: 'line',
//plugins: [ChartAnnotation],
data: {
labels: timeLabelList,
datasets: [
{
label: 'Goal',
yAxisID: 'A',
data: goalList,
//backgroundColor: chartColumnColorBlueSolid,
borderColor: chartColumnColorGreenSolid,
borderWidth: 2,
pointStyle: 'star'
}]
},
options: {
annotation: {
annotations: [
{
id: "a-line-1",
type: "line",
mode: "vertical",
scaleID: "y-axis-0",
value: "1",
borderColor: "red",
borderWidth: 2
}
]
},
legend: {
position: 'bottom',
display: true,
},
elements: {
line: {
tension: 0
}
},
scales: {
xAxes: [{
stacked: true,
type: 'time',
time: {
unit: 'hour'
},
}],
yAxes: [{
stacked: false,
id: 'A',
type: 'linear',
position: 'right',
}]
},
}
});
}
I tried all possible ways to register and also different ways to used the plugin but had no luck plotting it. I even used latest CDN versions but had no luck.
Can anyone help with it.
Thanks!

ChartJS align bars to left instead of center

I have a relatively simple bar chart in my application.
Code:
new Chart(document.getElementById("foo"), {
type: "bar",
options: {
scales: {
yAxes: [{
display: false,
}],
xAxes: [{
display: false,
}]
},
elements: {
bar: {
borderWidth: 2,
borderColor: "#D2DDEC"
},
point: {
hoverRadius: 0
},
},
legend: {
display: false,
},
},
data: {
labels: Object.keys(values),
datasets: [{
data: Object.values(values),
}]
}
})
However, these bars will center in the middle of the container, while I would like these to start left.
Is there a way to do this? I don't see any align property in the API.

I've just added labels until I reached 31. fixed.

How do I create a legend for a bar chart?

How do I create legends like the following:
So far I have the following:
I can't figure out how to specify labels for the legend. They don't provide examples either.
https://www.chartjs.org/docs/latest/configuration/legend.html
So far I have the following code:
var topClickSourcesChart = new Chart('dashboard-click-source-chart', {
type: 'bar',
data: {
labels: ["Facebook","Google","NONE",],
datasets: [{
data: [10,5,3,],
backgroundColor: ['#4D90C3', '#866DB2', '#EA6F98', '#61BDF6', '#768BB7'],
}],
},
options: {
scales: {
xAxes: [{
display: false,
}]
},
legend: {
position: 'right',
labels: {
boxWidth: 10,
}
}
}
});

To show a legend you need to set the label property of a dataset, so the type of output you are expecting can be built by creating a chart from the code as shown below. Fiddle -> https://jsfiddle.net/6nkcx8sq/
var topClickSourcesChart = new Chart('dashboard-click-source-chart', {
type: 'bar',
data: {
labels: ["Number of users"],
datasets: [{
label: 'Facebook',
data: [10],
backgroundColor: '#4D90C3',
},
{
label: 'Instagram',
data: [15],
backgroundColor: '#866DB2',
},
{
label: 'Twitter',
data: [7],
backgroundColor: '#EA6F98',
}],
},
options: {
scales: {
xAxes: [{
display: false,
}],
yAxes: [{
ticks: {
beginAtZero: true
}
}]
},
legend: {
position: 'right',
labels: {
boxWidth: 10,
}
}
}
});

I was able to get it with the following, but it was a pain in the ass for loops due to the backgroundColor having to be inside the dataset.
var topClickSourceChart = new Chart('dashboard-click-source-chart', {
type: 'bar',
data: {
labels: ["Facebook","Google","NONE",],
datasets: [
{label: "Facebook", data: [10]},{label: "Google", data: [5]},{label: "NONE", data: [3]},
]
},
options: {
scales: {
xAxes: [{
display: false,
}],
yAxes: [{
ticks: {
beginAtZero: true,
}
}]
},
legend: {
position: 'right',
labels: {
boxWidth: 10,
}
}
}
});
if (topClickSourceChart.data.datasets.length > 0) topClickSourceChart.data.datasets[0].backgroundColor = '#4D90C3';
if (topClickSourceChart.data.datasets.length > 1) topClickSourceChart.data.datasets[1].backgroundColor = '#866DB2';
if (topClickSourceChart.data.datasets.length > 2) topClickSourceChart.data.datasets[2].backgroundColor = '#EA6F98';
if (topClickSourceChart.data.datasets.length > 3) topClickSourceChart.data.datasets[3].backgroundColor = '#61BDF6';
if (topClickSourceChart.data.datasets.length > 4) topClickSourceChart.data.datasets[4].backgroundColor = '#768BB7';
Here is the JSP/JSTL loop:
data: {
labels: [<c:forEach items="${clickSources}" var="cs">"${cs.key}",</c:forEach>],
datasets: [
<c:forEach items="${clickSources}" var="cs">{label: "${cs.key}", data: [${cs.value}]},</c:forEach>
]
},
I still could not find a way to make the top of the bars rounded.

Chart.js 2.7: How to remove bar with value is 0 on the grouped bars?

I'm trying to remove the bar with value is 0 on grouped bar chart bars, but even though I see this solution many places it doesn't work for me.
What I want to do
I created this codepen. It contains a ChartJS grouped bar chart:
Vue.component('bar-chart', {
extends: VueChartJs.Bar,
mounted () {
this.renderChart({
labels: [1500,1600,1700,1750,1800,1850,1900],
datasets: [{
data: [168,17,0,190,0,276,108],
label: "Europe",
backgroundColor: "#3cba9f",
fill: false
}, {
data: [0,202,0,161,0,38,0],
label: "Asian",
backgroundColor: "#n8c9b2",
fill: false
},{
data: [0,202,0,161,224,38,0],
label: "Latin America",
backgroundColor: "#e8c3b9",
fill: false
}, {
data: [260,43,80,82,0,26,82],
label: "North America",
backgroundColor: "#c45850",
fill: false
}]
},
{
responsive: true,
maintainAspectRatio: false,
scales: {
xAxes: [{
categoryPercentage: 0.8,
barPercentage: 0.9
}],
yAxes: [{
scaleLabel: {
display: true
},
ticks: {
beginAtZero: true // minimum value will be 0.
}
}]
}
})
}
})
var vm = new Vue({
el: '.app'
})
Any idea on how to achieve the wanted behaviour?

Start bar-chart at 0 using ChartJS

I have a bar chart which use ChartJS that shows data. Based on the bar chart, I have the data: 15, 2, 0, 11.
I can see all of these data in the bar, except 0. Is there a possibility to start the bar chart on 0, so I can also see the data for the fourth column in the bar chart?
options: {
legend: { display: false },
scales: {
yAxes: [{
display: false,
}],
xAxes: [{
display: true,
}],
},
title: {
display: false,
}
}

After hours of working, finally i found a soulution. There is no chartjs configuration to do it and you have to draw it your self. Let do it in onComplete function
var ctx = document.getElementById("myChart").getContext('2d');
var datasets = [15, 2, 0, 11];
var myChart = new Chart(ctx, {
type: 'bar',
data: {
labels: ["1", "2", "3", "4"],
datasets: [{
label: 'value',
backgroundColor: '#F00',
data: datasets
}]
},
options: {
scales: {
yAxes: [{
ticks: {
beginAtZero: true
}
}]
},
animation: {
onComplete: function() {
var dataSet = myChart.getDatasetMeta(0);
dataSet.data.forEach(elm => {
if (datasets[elm._index] == 0) {
ctx.fillStyle = '#F00';
ctx.fillRect(elm._model.x - elm._view.width / 2, elm._model.y - 1, elm._view.width, 2);
}
})
}
}
}
});
<script src="https://cdnjs.cloudflare.com/ajax/libs/Chart.js/2.6.0/Chart.min.js"></script>
<canvas class="canvasChart" id="myChart"></canvas>

You can try beginAtZero:true config option.
options: {
legend: { display: false },
scales: {
yAxes: [{
display: false,
ticks: {
beginAtZero:true
}
}],
xAxes: [{
display: true,
}],
},
title: {
display: false,
}
}

Because your Y-axis values starts from 0 to something. So, if your value is 0 in X-Axis than it would be null and won't show you bar of 0. So, if you want 0 to appear in chart your starting point should be less than the 0.

I believe you said you were using chartsjs. This question already has an answer here.

Try this, chart will start with zero.
options: {
responsive: true,
scales: {
yAxes: [{
ticks: {
beginAtZero: true
}
}]
}
}
});