这可能是使用 d3js 创建的最简单的图表。然而我还在挣扎。
该图运行在 enter() 和 exit() 中给它的所有内容。但是 ENTER + UPDATE 中的所有内容都被完全忽略了。为什么?
// 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();
});
这是作为“数据”提供给更新函数的 json 结构的一个示例:
[{"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"}]