I am facing issues with the zoom function in D3 while using v4. It throws up an error saying that zoom.translate is not defined. I am mostly using the following code from this answer d3 focus on node on click, which worked perfectly for v3. However, as I was having issues with v3 as it has restrictions with data where the source and nodes are in the form of strings(instead of indices) D3 JSON file with source and index as strings rather than indices, I switched to v4.
<!DOCTYPE html>
<meta charset="utf-8">
<style>
.links line {
stroke: #999;
stroke-opacity: 0.6;
}
.nodes circle {
stroke: #fff;
stroke-width: 1.5px;
}
</style>
<svg width="960" height="600"></svg>
<script src="https://d3js.org/d3.v4.min.js"></script>
<script>
var svg = d3.select("svg"),
width = +svg.attr("width"),
height = +svg.attr("height")
active = d3.select(null);
var zoom = d3.zoom()
.scaleExtent([1, 8])
.on("zoom", zoomed);
var color = d3.scaleOrdinal(d3.schemeCategory20);
var simulation = d3.forceSimulation()
.force("link", d3.forceLink().id(function(d) { return d.id; }))
.force("charge", d3.forceManyBody())
.force("center", d3.forceCenter(width / 2, height / 2));
d3.json("graph.json", function(error, graph) {
if (error) throw error;
var link = svg.append("g")
.attr("class", "links")
.selectAll("line")
.data(graph.links)
.enter().append("line")
.attr("stroke-width", function(d) { return Math.sqrt(d.value); });
var node = svg.append("g")
.attr("class", "nodes")
.selectAll("circle")
.data(graph.nodes)
.enter().append("circle")
.attr("r", 5)
.attr("fill", function(d) { return color(d.group); })
.call(d3.drag()
.on("start", dragstarted)
.on("drag", dragged)
.on("end", dragended))
.on("click", clicked);
node.append("title")
.text(function(d) { return d.id; });
simulation
.nodes(graph.nodes)
.on("tick", ticked);
simulation.force("link")
.links(graph.links);
function ticked() {
link
.attr("x1", function(d) { return d.source.x; })
.attr("y1", function(d) { return d.source.y; })
.attr("x2", function(d) { return d.target.x; })
.attr("y2", function(d) { return d.target.y; });
node
.attr("cx", function(d) { return d.x; })
.attr("cy", function(d) { return d.y; });
}
});
function dragstarted(d) {
if (!d3.event.active) simulation.alphaTarget(0.3).restart();
d.fx = d.x;
d.fy = d.y;
}
function dragged(d) {
d.fx = d3.event.x;
d.fy = d3.event.y;
}
function dragended(d) {
if (!d3.event.active) simulation.alphaTarget(0);
d.fx = null;
d.fy = null;
}
function clicked(d){
if (active.node() === this) return reset();
active.classed("active", false);
active = d3.select(this).classed("active", true);
var bbox = active.node().getBBox(),
bounds = [[bbox.x, bbox.y],[bbox.x + bbox.width, bbox.y + bbox.height]];
var dx = bounds[1][0] - bounds[0][0],
dy = bounds[1][1] - bounds[0][1],
x = (bounds[0][0] + bounds[1][0]) / 2,
y = (bounds[0][1] + bounds[1][1]) / 2,
scale = Math.max(1, Math.min(8, 0.9 / Math.max(dx / width, dy / height))),
translate = [width / 2 - scale * x, height / 2 - scale * y];
svg.transition()
.duration(750)
.call(zoom.translate(translate).scale(scale).event);
}
function reset() {
active.classed("active", false);
active = d3.select(null);
svg.transition()
.duration(750)
.call(zoom.translate([0, 0]).scale(1).event);
}
function zoomed() {
console.log(d3.event)
g.style("stroke-width", 1.5 / d3.event.scale + "px");
g.attr("transform", "translate(" + d3.event.translate + ")scale(" + d3.event.scale + ")");
}
</script>
I changed d3.behaviour.zoom() to d3.zoom() and even changed
.call(zoom.translate(translate).scale(scale).event);
to
.call(d3.zoom().on("zoom", function () {
svg.attr("transform", d3.event.transform)
}));
which throws up a strange error, error: unknown type: wheel
What would be the best way to go about overcoming this situation?
