d3.js Bar Chart facing issue with tooltip - d3.js

Question

I have the following d3.js script to create bar chart which works fine.
I added functionality to show tool tip (not sure whether i added it at right place or not) which works fine but it has created an issue with existing mouseout event.
Issue:
The issue is that the following code is not working anymore. When i mouse over it does not turn into grey.
.on('mouseout', function (d) {
d3.select(this)
.attr('fill', 'blue');
However, if i comment the following lines than above mouseout event works perfect.
.on('mouseover', tip.show)
.on('mouseout', tip.hide)
Complete Script
var jsonData = #Html.Raw(Json.Encode(Model));
data = jsonData;
InitChart();
function InitChart() {
var barData = data;
var vis = d3.select('#SummaryChart'),
WIDTH = 500,
HEIGHT = 375,
MARGINS = {
top: 20,
right: 20,
bottom: 20,
left: 150
},
xRange = d3.scale.ordinal().rangeRoundBands([MARGINS.left, WIDTH - MARGINS.right], 0.1).domain(barData.map(function (d) {
return d.Date;
})),
yRange = d3.scale.linear().range([HEIGHT - MARGINS.top, MARGINS.bottom]).domain([0,
d3.max(barData, function (d) {
return d.Duration;
})
]),
xAxis = d3.svg.axis()
.scale(xRange)
.tickSize(0)
.tickSubdivide(true),
yAxis = d3.svg.axis()
.scale(yRange)
.tickSize(0)
.orient("left")
.tickSubdivide(true);
var tip = d3.tip()
.attr('class', 'd3-tip')
.offset([-10, 0])
.html(function(d) {
return "<strong>Duration:</strong> <span style='color:red'>" + d.Duration + "</span>";
})
vis.call(tip);
vis.append('svg:g')
.attr('class', 'x axis')
.attr('transform', 'translate(0,' + (HEIGHT - MARGINS.bottom) + ')')
.call(xAxis);
vis.append('svg:g')
.attr('class', 'y axis')
.attr('transform', 'translate(' + (MARGINS.left) + ',0)')
.call(yAxis);
vis.append("text")
.attr("class", "x label")
.attr("text-anchor", "end")
.attr("font-size", "20px")
.attr("x", WIDTH)
.attr("y", HEIGHT + 20)
.text("Time");
vis.append("text")
.attr("class", "y label")
.attr("text-anchor", "end")
.attr("font-size", "20px")
.attr("y", 100)
.attr("x",-100)
.attr("dy", ".75em")
.attr("transform", "rotate(-90)")
.text("Hours:");
vis.selectAll('rect')
.data(barData)
.enter()
.append('rect')
.attr('x', function (d) {
return xRange(d.Date);
})
.attr('y', function (d) {
return yRange(d.Duration);
})
.attr('width', xRange.rangeBand())
.attr('height', function (d) {
return ((HEIGHT - MARGINS.bottom) - yRange(d.Duration));
})
.attr('fill', 'blue')
.on('mouseover', function (d) {
d3.select(this)
.attr('fill', 'grey');
})
.on('mouseout', function (d) {
d3.select(this)
.attr('fill', 'blue');
})
.on('mouseover', tip.show)
.on('mouseout', tip.hide)
}
</script>
Can someone point out what is wrong and how i cam make it working with both tooltip and on mouse turning into grey working both together?

Answer 1

Unlike jQuery, D3 allows only a single callback per action. Therefore if you attach two .on('mouseout') callbacks, only the last one will execute. See:
d3.select('div')
.on('mouseout', function() {console.log('A')})
.on('mouseout', function() {console.log('B')})
<script src="https://cdnjs.cloudflare.com/ajax/libs/d3/3.4.11/d3.min.js"></script>
<div style='width:250px;height:250px;background:red'></div>
You have two ways around this. One, as suggested in comments, would be to call both attr and tooltip in the callback, as this:
.on('mouseout', function (d) {
d3.select(this).attr('fill', 'blue');
tip.hide();
}
Second would be to use the dot . notation, as described in the API, second paragraph
If an event listener was already registered for the same type on the selected element, the existing listener is removed before the new listener is added. To register multiple listeners for the same event type, the type may be followed by an optional namespace, such as "click.foo" and "click.bar".
So in your case
.on('mouseout.attr', function (d) {
d3.select(this)
.attr('fill', 'blue');
})
.on('mouseout.tip', tip.hide)
Working example:
d3.select('div')
.on('mouseout.logA', function() {console.log('A')})
.on('mouseout.logB', function() {console.log('B')})
<script src="https://cdnjs.cloudflare.com/ajax/libs/d3/3.4.11/d3.min.js"></script>
<div style='width:250px;height:250px;background:red'></div>