d3 real time chart legend design - d3.js

This is the final updated code. In a update function that takes a dataset object this code will render a real time legend. Other chart elements can be initialized when the script is loaded and the enter, update and exit selections for those belong in the update function as well. Maybe it is useful. Was for me. I think I can add this to any chart. Working fiddle
var legendG = svg.selectAll(".legend")
.data(donut(dataset), function (d) {
return d.data.label;
})
var legendEnter = legendG.enter();
legendEnter = legendEnter.append("g")
.attr("class", "legend");
//Now merge Enter and Update and adjust the location
legendEnter.merge(legendG)
.attr("transform", function (d, i) { return "translate(" + (width
- 350) + "," + (i * 15 + 20) + ")"; })
.attr("class", "legend");
legendG.exit().remove();
// Apend only to the enter selection
legendEnter.append("text")
.text(function (d) {
return d.data.label;
})
.style("font-size", 12)
.attr("y", 10)
.attr("x", 11);
//Now merge Enter and Update the legend color
legendEnter.merge(legendG)
.append("rect")
.attr("width", 10)
.attr("height", 10)
.attr("fill", function (d, i) {
console.log('index: ' + i + ' ' + d.data.label)
var c = color(i);
return c;
});

You should update the transform attribute of the update and enter selection together after merging the selection:
var legendG = svg.selectAll(".legend")
.data(donut(dataset), function (d) {
return d.data.label;
})
var legendEnter= legendG.enter().append("g")
.attr("class", "legend");
//Now merge Enter and Updatge and adjust the location
legendEnter.merge(legendG)
.attr("transform", function (d, i) { return "translate(" + (width - 500) + "," + (i * 15 + 20) + ")"; })
.attr("class", "legend");
legendG.exit().remove();
// Apend only to the enter selection
legendEnter.append("rect")
.attr("width", 10)
.attr("height", 10)
.attr("fill", function (d, i) {
return color(i);
});
...
Updated fiddle from previous post:fiddle

Related

Problems about update, enter, exit data and select in d3.js

I'm doing a visual project to show natural disaster in 1900-2018 using d3. I want add an interactive action that one can choose the first year and last year to show.
Originally I create the picture as the following:
d3.csv("output.csv", rowConventer, function (data) {
dataset = data;
var xScale = d3.scaleBand()
.domain(d3.range(dataset.length))
.range([padding, width - padding])
.paddingInner(0.05);
var yScale = d3.scaleLinear()
.domain([0,
d3.max(dataset, function (d) {
return d.AllNaturalDisasters;
})])
.range([height - padding, padding])
.nice();
stack = d3.stack().keys(["Drought", "Earthquake", "ExtremeTemperature", "ExtremeWeather", "Flood", "Impact", "Landslide", "MassMovementDry", "VolcanicActivity", "Wildfire"]);
series = stack(dataset);
gr = svg.append("g");
groups = gr.selectAll("g")
.data(series)
.enter()
.append("g")
.style("fill", function(d, i) {
return colors(i);
})
.attr("class", "groups");
rects = groups.selectAll("rect")
.data(function(d) { return d; })
.enter()
.append("rect")
.attr("x", function(d, i) {
return xScale(i);
})
.attr("y", function(d) {
return yScale(d[1]);
})
.attr("height", function(d) {
return yScale(d[0]) - yScale(d[1]);
})
.attr("width", xScale.bandwidth())
.append("title")
.text(function (d) {
var rect = this.parentNode;// the rectangle, parent of the title
var g = rect.parentNode;// the g, parent of the rect.
return d.data.Year + ", " + d3.select(g).datum().key + "," + (d[1]-d[0]);
});
d3.select("button")
.on("click", choosePeriod);
I have simplified some code to make my question simple. At the last row, I add an event listener to achieve what I described above. And the update function is choosePeriod. Now it is as following:
function choosePeriod() {
firstYear = parseInt(document.getElementById("FirstYear").value);
lastYear = parseInt(document.getElementById("LastYear").value);
d3.csv("output.csv", rowConventer, function (newdata) {
dataset = newdata;
series=stack(dataset);
groups.data(series);
groups.selectAll("rect")
.data(function (d) {
return d;
})
.enter()
.append("rect")
.attr("x", function(d, i) {
return xScales(i);
})
.attr("y", function(d) {
return yScales(d[1]);
})
.attr("height", function(d) {
return yScales(d[0]) - yScales(d[1]);
})
.attr("width", xScales.bandwidth())
.append("title")
.text(function (d) {
var rect = this.parentNode;// the rectangle, parent of the title
var g = rect.parentNode;// the g, parent of the rect.
return d.data.Year + ", " + d3.select(g).datum().key + "," + (d[1]-d[0]);
});
groups.selectAll("rect")
.data(function (d) {
return d;
})
.exit()
.remove();
})
}
The change of dataset is achieved by rowConventer, which is not important in this question. Now the functionchoosePeriod is not running as envisioned! Theenter and the exit and update are all not work well! The whole picture is a mess! What I want is, for instance, if I input the firstYear=1900 and the lastYear=2000, then the picture should be updated with the period 1900-2000 to show. How can I achieve it?
I am unfamiliar the arrangement of the entire structure, I mean, at some place using d3.select() by class or id instead of label is better, right?
It looks like you've dealt with the enter and the exit selections. The only bit you're missing is the update selection, which will deal with the rectangles that already exist and don't need adding or removing. To do this copy your update pattern but just remove the enter().append() bit, e.g.:
groups.selectAll("rect")
.data(function (d) {
return d;
})
.attr("x", function(d, i) {
return xScales(i);
})
.attr("y", function(d) {
return yScales(d[1]);
})
.attr("height", function(d) {
return yScales(d[0]) - yScales(d[1]);
})
.attr("width", xScales.bandwidth())
.append("title")
.text(function (d) {
var rect = this.parentNode;// the rectangle, parent of the title
var g = rect.parentNode;// the g, parent of the rect.
return d.data.Year + ", " + d3.select(g).datum().key + "," + (d[1]-d[0]);
})

How to update data elements within a transition without deleting a re-creating everything?

I'm using d3js v3 have a heat map that upon changing a ratio button selection I would switch the data from one dataset to another. The initialization requires a lot of steps e.g.
var svg = d3.select("#myId").append("svg");
...
var heatNode = svg.append("g");
heatNode.selectAll(".cellrect")
.data(data, function(d) { return d.row + ":" + d.col; })
.enter()
.append("rect")
.attr("x", function(d) { return (d.col - 1) * (cellWidth + cellMargin); })
.attr("y", function(d) { return (d.row - 1) * (cellHeight + + cellMargin); })
.attr("class", function(d) { return "cell cell-border cr" + (d.row-1) + " cc" + (d.col-1); })
.attr("width", cellWidth)
.attr("height", cellHeight)
.style("fill", function(d) { return colorScale(d.value); })
.on("mouseover", function(d) {
// highlight text
d3.select(this).classed("cell-hover", true);
d3.selectAll(id + " .rowLabel").classed("text-highlight", function(r, ri) { return ri == (d.row - 1); });
d3.selectAll(id + " .colLabel").classed("text-highlight", function(c, ci) { return ci == (d.col - 1); });
})
.on("mouseout", function(d) {
d3.select(this).classed("cell-hover", false);
d3.selectAll(id + " .rowLabel").classed("text-highlight", false);
d3.selectAll(id + " .colLabel").classed("text-highlight", false);
});
and now I get new data and would like to update only the fill color and nothing else. So I have tried without succcess:
heatNode.selectAll(".cellrect").transition().duration(2000)
.data(newData, function(d) { return d.row + ":" + d.col; })
.style("fill", function(d) { return colorScale(d.value); });
The only way that has worked for me so far is doing an ugly:
heatNode.selectAll("*").transition().duration(2000).remove();
and recreating everything again, however, not even then the transition works for me.
The code seems right but you need to add cellrect class to the first selection if you want to use this class to select the elements again
heatNode.selectAll(".cellrect")
.data(data, function(d) { return d.row + ":" + d.col; })
.enter()
.append("rect")
.attr("x", function(d) { return (d.col - 1) * (cellWidth + cellMargin);})
.attr("y", function(d) { return (d.row - 1) * (cellHeight + + cellMargin); })
.attr("class", function(d) { return "cellrect cell cell-border cr" + (d.row-1) + " cc" + (d.col-1); })
...

Unable to change x position of legend text inside a group element using D3

I am trying to create a horizontal graph legend in D3.js. I am using a group element (g) as a container for all the legends and the individual legends (text) are also each wrapped inside a "g" element. The result is that the individual legends are stacked on top of each other rather than spaced out.
I have tried changing the x attribute on the legends and also transform/translate. Whilst the DOM shows that the x values are applied the legends don't move. So if the DOM shows the legend / g element is positioned at x = 200 it is still positioned at 0.
I have spent two days trying to solve this and probably looked at over 50 examples including anything I could find on StackExchange.
Below code is my latest attempt. It doesn't through any error and the x values are reflected in the DOM but the elements just won't move.
I have included the code covering the relevant bits (but not all code).
The legend container is added here:
/*<note>Add container to hold legends. */
var LegendCanvas = d3.select("svg")
.append("g")
.attr("class", "legend canvas")
.attr("x", 0)
.attr("y", 0)
.attr("width", Width)
.style("fill", "#ffcccc")
.attr("transform", "translate(0,15)");
There is then a loop through a json array of objects:
var PrevElemLength = 0;
/*<note>Loop through each data series, call the Valueline variable and plot the line. */
Data.forEach(function(Key, i) {
/*<note>Add the metric line(s). */
Svg.append("path")
.attr("class", "line")
.attr("data-legend",function() { return Key.OriginId })
/*<note>Iterates through the data series objects and applies a different color to each line. */
.style("stroke", function () {
return Key.color = Color(Key.UniqueName); })
.attr("d", Valueline(Key.DataValues));
/*<note>Add a g element to the legend container. */
var Legend = LegendCanvas.append("g")
.attr("class", "legend container")
.attr("transform", function (d, i) {
if (i === 0) {
return "translate(0,0)"
} else {
PrevElemLength += this.previousElementSibling.getBBox().width;
return "translate(" + (PrevElemLength) + ",0)"
}
});
/*<note>Adds a rectangle to pre-fix each legend. */
Legend.append("rect")
.attr("width", 5)
.attr("height", 5)
.style("fill", function () {
return Key.color = Color(Key.UniqueName); });
/*<note>Adds the legend text. */
Legend.append("text")
.attr("x", function() {
return this.parentNode.getBBox().width + 5;
})
/*.attr("y", NetHeight + (Margin.bottom/2)+ 10) */
.attr("class", "legend text")
.style("fill", function () {
return Key.color = Color(Key.UniqueName); })
.text(Key.UniqueName);
Here is a screen shot of what the output looks like:
enter image description here
Any help on how to create a horizontal legend (without over lapping legends) would be much appreciated. Chris
The problem is you are using local variables d and i as function parameters while setting the transform attribute. Parameter i in local scope overrides the actual variable. The value of local variable i would be always zero as there is no data bind to that element.
var Legend = LegendCanvas.append("g")
.attr("class", "legend container")
.attr("transform", function (d, i) { //Remove i
if (i === 0) {
return "translate(0,0)"
} else {
PrevElemLength += this.previousElementSibling.getBBox().width;
return "translate(" + (PrevElemLength) + ",0)"
}
});
I have also made slight updates to the code for improvements.
var LegendCanvas = d3.select("svg")
.append("g")
.attr("class", "legend canvas")
.attr("x", 0)
.attr("y", 0)
.attr("width", 500)
.style("fill", "#ffcccc")
.attr("transform", "translate(0,15)");
var PrevElemLength = 0;
var Data = [{
OriginId: 1,
UniqueName: "Some Long Text 1"
}, {
OriginId: 2,
UniqueName: "Some Long Text 2"
}];
/*<note>Loop through each data series, call the Valueline variable and plot the line. */
var Color = d3.scale.category10();
Data.forEach(function(Key, i) {
/*<note>Add a g element to the legend container. */
var Legend = LegendCanvas.append("g")
.attr("class", "legend container")
.attr("transform", function() {
if (i === 0) {
return "translate(0,0)"
} else {
var marginLeft = 5;
PrevElemLength += this.previousElementSibling.getBBox().width;
return "translate(" + (PrevElemLength + marginLeft) + ",0)"
}
});
/*<note>Adds a rectangle to pre-fix each legend. */
Legend.append("rect")
.attr("width", 5)
.attr("height", 5)
.style("fill", function() {
return Key.color = Color(Key.UniqueName);
});
/*<note>Adds the legend text. */
Legend.append("text")
.attr("x", function() {
return this.parentNode.getBBox().width + 5;
})
.attr("dy", "0.4em")
.attr("class", "legend text")
.style("fill", function() {
return Key.color = Color(Key.UniqueName);
})
.text(Key.UniqueName);
});
<script src="https://cdnjs.cloudflare.com/ajax/libs/d3/3.4.11/d3.min.js"></script>
<svg height=500 width=500></svg>
The d3 way of implementation(Using data binding) would be as follows
var LegendCanvas = d3.select("svg")
.append("g")
.attr("class", "legend canvas")
.attr("x", 0)
.attr("y", 0)
.attr("width", 500)
.style("fill", "#ffcccc")
.attr("transform", "translate(0,15)");
var Data = [{
OriginId: 1,
UniqueName: "Some Long Text 1"
}, {
OriginId: 2,
UniqueName: "Some Long Text 2"
}];
var Color = d3.scale.category10();
var Legend = LegendCanvas.selectAll(".legend")
.data(Data)
.enter()
.append("g")
.attr("class", "legend container");
Legend.append("rect")
.attr("width", 5)
.attr("height", 5)
.style("fill", function(Key) {
return Key.color = Color(Key.UniqueName);
});
Legend.append("text")
.attr("x", function() {
return this.parentNode.getBBox().width + 5;
})
.attr("dy", "0.4em")
.attr("class", "legend text")
.style("fill", function(Key) {
return Key.color = Color(Key.UniqueName);
})
.text(function(Key){ return Key.UniqueName });
var PrevElemLength = 0;
Legend.attr("transform", function(d, i) {
if (i === 0) {
return "translate(0,0)"
} else {
var marginLeft = 5;
PrevElemLength += this.previousElementSibling.getBBox().width;
return "translate(" + (PrevElemLength + marginLeft) + ",0)"
}
});
<script src="https://cdnjs.cloudflare.com/ajax/libs/d3/3.4.11/d3.min.js"></script>
<svg width=500 height=500></svg>
Try this :
//Legend
var legend = vis.selectAll(".legend")
.data(color.domain())
.enter().append("g")
.attr("class", "legend")
.attr("transform", function(d, i) { return "translate(0," + i * 20 + ")"; });
legend.append("image")
.attr("x", 890)
.attr("y", 70)
.attr("width", 20)
.attr("height", 18)
.attr("xlink:href",function (d) {
return "../assets/images/dev/"+d+".png";
})
legend.append("text")
.attr("x", 910)
.attr("y", 78)
.attr("dy", ".35em")
.style("text-anchor", "start")
.text(function(d) {
return d;
});

D3 drag error 'Cannot read property x of undefined'

I'm trying to get drag functionality to work on D3, and have copied the code directly from the developer's example.
However it seems the origin (what is being clicked) is not being passed correctly into the variable d, which leads to the error: 'Cannot read property 'x' of undefined'
The relevant code:
var drag = d3.behavior.drag()
.on("drag", function(d,i) {
d.x += d3.event.dx
d.y += d3.event.dy
d3.select(this).attr("transform", function(d,i){
return "translate(" + [ d.x,d.y ] + ")"
})
});
var svg = d3.select("body").append("svg")
.attr("width", 1000)
.attr("height", 300);
var group = svg.append("svg:g")
.attr("transform", "translate(10, 10)")
.attr("id", "group");
var rect1 = group.append("svg:rect")
.attr("rx", 6)
.attr("ry", 6)
.attr("x", 5/2)
.attr("y", 5/2)
.attr("id", "rect")
.attr("width", 250)
.attr("height", 125)
.style("fill", 'white')
.style("stroke", d3.scale.category20c())
.style('stroke-width', 5)
.call(drag);
Usually, in D3 you create elements out of some sort of datasets. In your case you have just one (perhaps, one day you'll want more than that). Here's how you can do it:
var data = [{x: 2.5, y: 2.5}], // here's a dataset that has one item in it
rects = group.selectAll('rect').data(data) // do a data join on 'rect' nodes
.enter().append('rect') // for all new items append new nodes with the following attributes:
.attr('x', function (d) { return d.x; })
.attr('y', function (d) { return d.y; })
... // other attributes here to modify
.call(drag);
As for the 'drag' event handler:
var drag = d3.behavior.drag()
.on('drag', function (d) {
d.x += d3.event.dx;
d.y += d3.event.dy;
d3.select(this)
.attr('transform', 'translate(' + d.x + ',' + d.y + ')');
});
Oleg's got it, I just wanted to mention one other thing you might do in your case.
Since you only have a single rect, you can bind data directly to it with .datum() and not bother with computing a join or having an enter selection:
var rect1 = svg.append('rect')
.datum([{x: 2.5, y: 2.5}])
.attr('x', function (d) { return d.x; })
.attr('y', function (d) { return d.y; })
//... other attributes here
.call(drag);

D3js PieChart will not perform UPDATE section

This is probably the simplest graph possible to create using d3js. And yet I am struggling.
The graph runs everything given to it in enter() and exit(). But everything in ENTER + UPDATE is completely ignored. WHY?
// Setup dimensions
var width = 200,
height = 200,
radius = Math.min(width, height) / 2,
// Setup a color function with 20 colors to use in the graph
color = d3.scale.category20(),
// Configure pie container
arc = d3.svg.arc().outerRadius(radius - 10).innerRadius(0), // Define the arc element
svg = d3.select(".pie").append("svg:svg")
.attr("width", width)
.attr("height", height)
.append("g")
.attr("transform", "translate(" + width / 2 + "," + height / 2 + ")"),
// This is the layout manager for the pieGraph
pie = d3.layout.pie()
.sort(null)
.value(function (d) {
return d.answers;
}),
// Allow two groups in the container. One overlapping the other, just to make sure that
// text labels never get hidden below pie arcs.
graphGroup = svg.append("svg:g").attr("class", "graphGroup"),
textGroup = svg.append("svg:g").attr("class", "labelGroup");
// Data is loaded upon user interaction. On angular $scope update, refresh graph...
$scope.$watch('answers', function (data) {
// === DATA ENTER ===================
var g = graphGroup.selectAll("path.arc").data(pie(data)),
gEnter = g.enter()
.append("path")
.attr("d", arc)
.attr("class", "arc"),
t = textGroup.selectAll("text.label").data(data),
tEnter = t.enter()
.append("text")
.attr("class", "label")
.attr("dy", ".35em")
.style("text-anchor", "middle");
// === ENTER + UPDATE ================
g.select("path.arc")
.attr("id", function (d) {
return d.data.id + "_" + d.data.selection;
})
.attr("fill", function (d, i) {
return color(i);
})
.transition().duration(750).attrTween("d", function (d) {
var i = d3.interpolate(this._current, d);
this._current = i(0);
return function (t) {
return arc(i(t));
};
});
t.select("text.label")
.attr("transform", function (d) {
return "translate(" + arc.centroid(d) + ")";
})
.text(function (d) {
return d.data.opt;
});
// === EXIT ==========================
g.exit().remove();
t.exit().remove();
});
This one example of the json structure given to the update function as "data":
[{"selection":"0","opt":"1-2 timer","answers":"7"},
{"selection":"1","opt":"3-4 timer","answers":"13"},
{"selection":"2","opt":"5-6 timer","answers":"5"},
{"selection":"3","opt":"7-8 timer","answers":"8"},
{"selection":"4","opt":"9-10 timer","answers":"7"},
{"selection":"5","opt":"11 timer eller mer","answers":"11"},
{"selection":"255","opt":"Blank","answers":"8"}]
You don't need the additional .select() to access the update selection. This will in fact return empty selections in your case, which means that nothing happens. To make it work, simply get rid of the additional .select() and do
g.attr("id", function (d) {
return d.data.id + "_" + d.data.selection;
})
// etc
t.attr("transform", function (d) {
return "translate(" + arc.centroid(d) + ")";
})
// etc

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