Unknown User Unknown User - 7 months ago 213
Javascript Question

Stacked Bar Chart Labels - D3

I'm trying to add data labels to stacked bar chart in d3.

I wanted the data labels to be in the middle of the bar. So far i just figured out how to add data labels on top of each bar. But actually i wanted those labels to be in the middle of each bar.

Here's my code :


var width = 750,
height = 500;

var x = d3.scale.ordinal()
.rangeRoundBands([0, width], .1);

var y = d3.scale.linear()
.rangeRound([height, 0]);

var color = d3.scale.ordinal()
.range(["#D70B16", "#154CEF", "#1A8A55"]);

var xAxis = d3.svg.axis()
.scale(x)
.orient("bottom");

var yAxis = d3.svg.axis()
.scale(y)
.orienta("left")
.tickFormat(d3.format(".2s"));

var tip = d3.tip()
.attr('class', 'd3-tip')
.offset([-10, 0])
.html(function(d) {
return "Value: " + (d.y1 - d.y0) + "";
})

var svgContainer = d3.select("body")
.append("svg")
.attr("width", width)
.attr("height", height)
.append("g")
.attr("transform", "translate(" + 30 + "," + 30 + ")");


d3.csv("data.csv", function(error, data) {
color.domain(d3.keys(data[0]).filter(function(key) {
return key !== "circle";
}));

data.forEach(function(d) {
var y0 = 0;
d.hours = color.domain().map(function(name) {
return {name: name, y0: y0, y1: y0 += +d[name]};
});

d3.select('body').append('pre')
.text(JSON.stringify(d.hours, null, ' '));

d.total = d.hours[d.hours.length - 1].y1;
});

x.domain(data.map(function(d) {return d.circle;}));
y.domain([0, d3.max(data, function(d) {return d.total;})])

svgContainer.append("g")
.attr("class", "x axis")
.attr("transform", "translate(0," + height + ")")
.call(xAxis);

svgContainer.append("g")
.attr("class", "y axis")
.call(yAxis)
.append("text")
.attr("transform", "rotate(-90)")
.attr("y", 6)
.attr("dy", ".71em")
.style("text-anchor", "end")
.text("Login Hours");

var circle = svgContainer.selectAll(".circle")
.data(data)
.enter().append("g")
.attr("class", "g")
.attr("transform", function(d) {
return "translate(" + x(d.circle) + ",0)";
});

circle.selectAll("rect")
.data(function(d) { return d.hours; })
.enter()
.append("rect")
.attr("width", x.rangeBand())
.attr("y", function(d) { return y(d.y1); })
.attr("height", function(d) { return y(d.y0) - y(d.y1); })
.on("mouseover", tip.show)
.on("mouseout", tip.hide)
.style("fill", function(d) { return color(d.name); });


circle.selectAll("text")
.data(function(d) { return d.hours; })
.enter()
.append("text")
.attr("x", 75)
.attr("y", function(d, i) { return y(d.y1) ; })
.style("text-anchor", "middle")
.text("test")

})


Data :

state,value1, value2, value3
state1, 80, 10, 20
state2, 90, 5, 10
state3, 70, 15, 35
state4, 90, 3, 27
state5, 50, 25, 55
state6, 85, 8, 27


I actually couldn't figure out how to get the mid point of X & Y co-ordinates of each bar.

Help me in arranging the labels in the middle of each bar.

Answer

You just need to adjust the y coordinate of the text elements:

circle.selectAll("text")
      .data(function(d) { return d.hours; })
      .enter()
      .append("text")
      .attr("x", 75)
      .attr("y", function(d, i) { return y(d.y1) + (y(d.y0) - y(d.y1))/2; })
      .style("text-anchor", "middle")
      .text("test")