Rishabh Rishabh - 5 months ago 15
AngularJS Question

AngularJS: Directive with D3 chart in link function working only once

I've created an AngularJS directive which contains a D3 chart, like below:

angular.module('main', [''])

.directive('barChart', function() {

return {

restrict: 'E',
replace: true,
scope: {
},
template: '<svg class="chart" width="250" height="100"></svg>',
link: function (scope, element, attrs, fn) {

var d3 = window.d3;

var data = {
labels: [
'LY', 'TY'
],
series: [{
label: 'LY',
values: [2.8]
}, {
label: 'TY',
values: [3.2]
}]
};


var chartWidth = 150,
barHeight = 30,
groupHeight = barHeight,
gapBetweenGroups = -10,
spaceForLabels = 50,
spaceForLegend = 50;

// Zip the series data together (first values, second values, etc.)
var zippedData = [];
for (var i = 0; i < data.labels.length; i++) {
for (var j = 0; j < data.series.length; j++) {
zippedData.push(data.series[i].values[j]);
}
}

// Color scale
var color = d3.scale.category20();
var chartHeight = barHeight * zippedData.length + gapBetweenGroups * data.labels.length;

var x, y, yAxis, chart, bar;

function setChartParameters() {
x = d3.scale.linear()
.domain([0, d3.max(zippedData)])
.range([0, chartWidth]);

y = d3.scale.linear()
.range([chartHeight + gapBetweenGroups, 0]);

yAxis = d3.svg.axis()
.scale(y)
.tickFormat('')
.tickSize(0)
.orient("left");

// Specify the chart area and dimensions
chart = d3.select(".chart")
.attr("width", spaceForLabels + chartWidth + spaceForLegend)
.attr("height", chartHeight);

// Create bars
bar = chart.selectAll("g")
.data(zippedData)
.enter().append("g")
.attr("transform", function (d, i) {
return "translate(" + spaceForLabels + "," + (i * barHeight + gapBetweenGroups * (0.5 + Math.floor(i / data.series.length))) + ")";
});
}

function drawBarChart() {

setChartParameters();

// Create rectangles of the correct width
bar.append("rect")
.attr("fill", function (d, i) {
return color(i);
})
.attr("class", "bar")
.attr("width", x)
.attr("height", barHeight - 1);

// Add text label in bar
bar.append("text")
.attr("x", function (d) {
return x(d) - (-30);
})
.attr("y", barHeight / 2)
.attr("fill", "red")
.attr("dy", ".35em")
.text(function (d) {
return d;
});

// Draw labels
bar.append("text")
.attr("class", "label")
.attr("x", function (d) {
return -10;
})
.attr("y", groupHeight / 2)
.attr("dy", ".35em")
.text(function (d, i) {
if (i % data.series.length === 0) {
return data.labels[Math.floor(i / data.series.length)];
} else {
return "";
}
});

chart.append("g")
.attr("class", "y axis")
.attr("transform", "translate(" + spaceForLabels + ", " + -gapBetweenGroups / 2 + ")")
.call(yAxis);
}

drawBarChart();

}
};

});


The problem is, when I am referencing this directive twice in the HTML, like this:

<bar-chart chart-data="chartData"></bar-chart>
<bar-chart chart-data="chartData"></bar-chart>


The chart is being created only 'once' (the second chart element is created but no chart is generated.enter image description here

Also, even if I try to create another directive with different name but same code and same template, the first directive works and second directive doesn't.

<bar-chart chart-data="chartData"></bar-chart>
<bar-chart2 chart-data="chartData"></bar-chart2>

Answer

As you can see in link, you must get svg element from element parameter of directive. Check this plunker https://plnkr.co/edit/TlTJWDfTPAWa1sDPQM7w?p=preview (sorry for problem of width and x). In the plunker I get svg element as :

chart = d3.select(rawSvg[0])...

and not

chart = d3.select(".chart")...

With this you can put multiple charts

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