我有很多传说。但我想一次只显示5个传说。我想要一个按钮，显示接下来的5个传说。任何人都可以帮我实现这个。
我实施了分页但最后我有两个重复的传说。 我的工作代码在 js fiddle
var data=[
{
"age":"<5",
"population":2704659
},
{
"age":"5-10",
"population":4499890
},
{
"age":"10-13",
"population":6736433
},
{
"age":"14-16",
"population":2159981
},
{
"age":"16-18",
"population":3853788
},
{
"age":"18-22",
"population":8848383
},
{
"age":"22-30",
"population":8384390
},
{
"age":"30-44",
"population":14106543
},
{
"age":"45-64",
"population":8819342
},
{
"age":"≥65",
"population":800000
}
]
var width = 1060,
height = 600,
radius = 175,
color = d3.scale.category10(),
legendNo=4, // number of legends to display at a time
legendCount=0; //To store number of legends
//creating svg element and appending to body
var svg = d3.select("body").append("svg")
.attr("width", width)
.attr("height", height)
.append("g")
.attr("transform", "translate(" + width / 2 + "," + height / 2 + ")"); //transform it to center of body
//creating start and end angle for each arc
var pie = d3.layout.pie()
.sort(null)
.value(function(d) { return d.population; });
//creating the arcs based on pie layout
var arc = d3.svg.arc() //inner arc with color
.outerRadius(radius)
.innerRadius(radius-70);
//calculate the total to display in hole
var total=0;
data.forEach(function(d) {
d.population;
total +=parseInt(d.population);
legendCount++;
});
//creating svg element for center text
var center_group = svg.append("svg:g")
.attr("class", "center_group")
.attr("transform", "translate(" + (width/2) + "," + (height/2) + ")");
//selecting all inner arcs and appending data
var g = svg.selectAll("arc")
.data(pie(data))
.enter().append("g")
.attr("class", "arc")
//giving colour to each inner arc and execute onClick function
g.append("path")
.attr("d", arc)
.style("fill", function(d) { return color(d.data.age); })
//display text in the inner arcs
g.append("text")
.attr("transform", function(d) { return "translate(" + arc.centroid(d) + ")"; })
.attr("dy", ".35em")
.style("text-anchor", "middle")
.style("font-size", "14px")
.text(function(d) { return d.data.age; });
count = 0;
var p=0;
var viewdata = data.slice(p,p+legendNo);
var hidedata;
var temp;
//selecting all legend elements
var legend = svg.selectAll(".legend")
.data(viewdata).enter()
.append("g").attr("class", "legend")
//.attr("width", )
.attr("id", function() {
return count++;
})
.attr("transform", function(d, i) {
return "translate("+(-(width/2-30)+ i * 50)+"," + (height/2-50)+ ")";
})
//appending coloured rectangles to legend
svg.selectAll("rect")
.data(viewdata)
.enter().append("rect")
.attr("x", width/2-150)
.attr("y",5)
.attr("dy", "3.00em")
.attr("dx", "1.75em")
.attr("width", 23).attr("height", 23)
.attr("transform", function(d, i) {
return "translate("+(-(width/2-30)+ i * 50)+"," + (height/2-50)+ ")";
})
.style("fill", function(d) {
return color(d.age);
});
var prev=svg.append("svg:text")
.attr("id","prev")
.attr("x", width-1260)
.attr("y",height-385)
.attr("dy", "2.90em")
.attr("dx", "1.75em")
//.attr("stroke", "black")
//.style("fill","white")
// .style("text-anchor", "middle")
.style("font-size", "20px")
//.attr("width", 45).attr("height", 25)
.text("<|")
.on("click",onPrevClick)
var next=svg.append("svg:text")
.attr("id","next")
.attr("x", width-950)
.attr("y",height-385)
.attr("dy", "2.90em")
.attr("dx", "1.75em")
.style("font-size", "20px")
//.attr("stroke", "black")
//.style("fill","white")
//.attr("width", 45).attr("height", 25)
.text("|>")
.on("click",onNextClick)
function onNextClick()
{p+=legendNo;
if(p>=legendCount){
p-=legendNo;
viewdata = data.slice(p,legendCount);
//temp=legendNo-(legendCount-p);
//hidedata =data.slice(p-temp-2,p-2);
}
else{
viewdata = data.slice(p,p+legendNo);
//hidedata =data.slice(0,0);
}
svg.selectAll("rect")
.data(viewdata)
.attr("x", width/2-150)
.attr("y",5)
.attr("dy", "3.00em")
.attr("dx", "1.75em")
.attr("width", 23).attr("height", 23)
.attr("transform", function(d, i) {
return "translate("+(-(width/2-30)+ i * 50)+"," + (height/2-50)+ ")";
})
.style("fill", function(d) {
return color(d.age);
});
legend.select("text").attr("x", width/2-150)
.data(viewdata)
.attr("y", 15)
.attr("dy", "3.00em")
.attr("dx", "1.75em")
//.attr("transform", function(d, i) {return "rotate("+45*i+","+d.age+",200)";})
.attr("text-anchor", "middle").text(function(d) {
return d.age;
});
}
function onPrevClick(){
p-=legendNo;
if(p<=0){
p=0;
}
viewdata = data.slice(p,p+legendNo);
svg.selectAll("rect")
.data(viewdata)
.attr("x", width/2-150)
.attr("y",5)
.attr("dy", "3.00em")
.attr("dx", "1.75em")
.attr("width", 23).attr("height", 23)
.attr("transform", function(d, i) {
return "translate("+(-(width/2-30)+ i * 50)+"," + (height/2-50)+ ")";
})
.style("fill", function(d) {
return color(d.age);
});
legend.select("text").attr("x", width/2-150)
.data(viewdata)
.attr("y", 15)
.attr("dy", "3.00em")
.attr("dx", "1.75em")
//.attr("transform", function(d, i) {return "rotate("+45*i+","+d.age+",200)";})
.attr("text-anchor", "middle").text(function(d) {
return d.age;
});
}
// giving text to legends
legend.append("text").attr("x", width/2-150)
.data(viewdata)
.attr("y", 15)
.attr("dy", "3.00em")
.attr("dx", "1.75em")
//.attr("transform", function(d, i) {return "rotate("+45*i+","+d.age+",200)";})
.attr("text-anchor", "middle").text(function(d) {
return d.age;
});
//displaying legend title
var legendTitle = svg.append("svg:text")
.attr("x", -(width/2-200))
.attr("y", height/2-25)
.style("font-size", "14px")
.style("text-decoration", "underline")
.text("Age Group");