Drag behavior returning NaN in D3

d3.js, javascript, svg

Solution

This is because `d3.event` relay to data, if you check in your code that:

.attr("x", function(d,i){console.log(d);return points[i]})

you will find that d is text, which can't have x,y properties.

the solution is to make each letter as object (you also splitted them by "," but i gues it should be "" ) so here the code:

var stage = d3.select("body").append("svg");
var points = [0, 50, 100, 150];
var letters = "drag".split("").map(function(d, i) {
    return {
        text: d,
        x: points[i],
        y: 100
    }
});
var log = d3.select("#log");

//drag behaviour, will bind later
var drag = d3.behavior
    .drag()
    .origin(Object)
    .on("drag", dragmove);


//append texts
var texts = stage
    .selectAll("text")
    .data(letters)
    .enter()
       .append("text")
       .attr("font-family", "Arial")
       .attr("class", "word")
       .attr("x", function(d, i) {
            return d.x;
       })
       .attr("y", 100)
       .text(function(d) {
            return d.text;
           })
       .call(drag);

function dragmove(d) {
    log.text(
        "x: " + d3.event.x + ", " + 
        "y: " + d3.event.y + ", " + 
        "dx: " + d3.event.dx + ", " + 
        "dy: " + d3.event.dy);
    //set new position to the object
    d.x=d3.event.x;
    d3.select(this).attr("x", d3.event.x);
}​

and fiddle

Problem

Original source