设想：
我从在线示例中获取的标准 D3 v3 强制布局开始。
我想加强这一点，我的目标是：
- 当脚本加载调用一个函数来初始化和渲染一些数据的图形
- 单击按钮以更新页面上的图形以优雅地添加/删除节点和链接- 即无需完全重新绘制节点“飞入”。
我想要的行为类型的一个示例是这个奇妙的图表，其中拖动阈值滑块“弹出”链接进/出而无需完全重新渲染，因此很容易看到已添加/删除的内容：http://jsfiddle。网络/simonraper/TdHgx/?utm_source=website&utm_medium=embed&utm_campaign=TdHgx
问题：
- 我不确定如何达到上述第 2 点。
- 我无法通过完全重绘来更新我的图表
- 我很确定答案与我如何使用 D3 通用更新模式有关。
这是我到目前为止的一个例子：https ://jsfiddle.net/samollason/uvqosxrr/3/
jsfiddle 的代码：
html:
<body>
<button id="update-button1">Update Data - Remove</button>
<button id="update-button2">Update Data - Add</button>
</body>
js：
var width = 400,
height = 500;
var force = d3.layout.force()
.size([width, height])
.charge(-400)
.linkDistance(40)
.on("tick", tick);
var drag = force.drag()
.on("dragstart", dragstart);
//Set up the force layout
var svg = d3.select("body").append("svg")
.attr("width", width)
.attr("height", height);
var link = svg.selectAll(".link"),
node = svg.selectAll(".node");
//we call this function when we first draw graph
var drawInit = function(graph){
link = link.data(graph.links, function(d) { return d.id; })
.enter().append("line")
.attr("class", "link");
node = node.data(graph.nodes, function(d) { return d.id; })
.enter().append("circle")
.attr("class", "node")
.attr("r", 12)
.on("dblclick", dblclick)
.call(drag);
force
.nodes(graph.nodes)
.links(graph.links)
.start();
};
//call this function whenever we want to update the graph
var update = function(graph){
link = link.data(graph.links, function(d) { return d.id; });
link.exit().remove();
link
.enter().append("line")
.attr("class", "link");
node = node.data(graph.nodes, function(d) { return d.id; });
//Remove nodes not in new data set
node.exit().remove();
//For each datum in dataset that wasn't in old dataset append
circle
node.enter().append("circle")
.attr("class", "node")
.attr("r", 12)
.on("dblclick", dblclick)
.call(drag);
//Update the force layout graph
force
.nodes(graph.nodes)
.links(graph.links)
.start();
};
function tick() {
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 dblclick(d) {
console.log("double clicked on " + d.name);
d3.select(this).classed("fixed", d.fixed = false);
}
function dragstart(d) {
d3.select(this).classed("fixed", d.fixed = true);
}
//data1 is used for our initial drawing
data1 = {
"nodes": [
{
"id":0,
"name": 0,
"group": 1,
"size": 10
},
{
"id":1,
"name": 1,
"group": 1,
"size": 10
},
{
"id":2,
"name": 2,
"group": 1,
"size": 20
},
{
"id":3,
"name": 3,
"group": 1,
"size": 30
},
{
"id":4,
"name": 4,
"group": 1,
"size": 25
}
],
"links": [
{
"source": 1, "target": 0, "value":1, "id":0
},
{
"source": 1, "target": 2, "value":1, "id":1
},
{
"source": 1, "target": 3, "value":1, "id":2
},
{
"source": 1, "target": 4, "value":1, "id":3
}
]
};
drawInit(data1);
//When user clicks on button update force layout graph *gracefully*
d3.select("#update-button1").on("click", function(e) {
var data2 = {
"nodes": [
{
"id": 0,
"name": 0,
"group": 1,
"size": 10
},
{
"id": 1,
"name": 1,
"group": 1,
"size": 10
},
{
"id": 2,
"name": 2,
"group": 1,
"size": 20
},
{
"id": 3,
"name": 3,
"group": 1,
"size": 30
}
],
"links": [
{
"source": 1, "target": 0, "value": 1, "id": 0
},
{
"source": 1, "target": 2, "value": 1, "id": 1
},
{
"source": 1, "target": 3, "value": 1, "id": 2
}
]
};
update(data2);
});
//When user clicks on button update force layout graph *gracefully*
d3.select("#update-button2").on("click", function(e) {
//this simulates removing a node
var data3 = {
"nodes": [
{
"id": 0,
"name": 0,
"group": 1,
"size": 10
},
{
"id": 1,
"name": 1,
"group": 1,
"size": 10
},
{
"id": 2,
"name": 2,
"group": 1,
"size": 20
},
{
"id": 3,
"name": 3,
"group": 1,
"size": 30
},
{
"id": 4,
"name": 4,
"group": 1,
"size": 30
},
{
"id": 5,
"name": 5,
"group": 1,
"size": 30
}
],
"links": [
{
"source": 1, "target": 0, "value": 1, "id": 0
},
{
"source": 1, "target": 2, "value": 1, "id": 1
},
{
"source": 1, "target": 3, "value": 1, "id": 2
},
{
"source": 1, "target": 4, "value": 1, "id": 3
},
{
"source": 1, "target": 5, "value": 1, "id": 4
}
]
};
update(data3);
});