【echarts】【前端】點擊圖例，只有被點擊圖例對應的折線顯示，其他隱藏

最近在做一個功能：用echarts做一張折線圖，圖中有多條線。在初始狀態，所有折線都顯示，然後點擊其中一個圖例，其他折線會隱藏。

借用了https://www.cnblogs.com/shj-com/p/11327072.html 的思路。在他的基礎上重寫了。

效果是這樣的（option設置使用了echarts的官方案例）：

剛初始化好：

點擊“郵件營銷”：

再點擊“聯盟廣告”：

 

$(document).ready(function(){
 var chart = echarts.init(document.getElementById('chart'));
 
     // for blog example - from https://www.echartsjs.com/examples/zh/editor.html?c=line-stack
    options = {
        title: {
        text: '折線圖堆疊'
    },
    tooltip: {
        trigger: 'axis'
    },
    legend: {
        data: ['郵件營銷', '聯盟廣告', '視頻廣告', '直接訪問', '搜索引擎']
    },
    grid: {
        left: '3%',
        right: '4%',
        bottom: '3%',
        containLabel: true
    },
    toolbox: {
        feature: {
            saveAsImage: {}
        }
    },
    xAxis: {
        type: 'category',
        boundaryGap: false,
        data: ['週一', '週二', '週三', '週四', '週五', '週六', '週日']
    },
    yAxis: {
        type: 'value'
    },
    series: [
        {
            name: '郵件營銷',
            type: 'line',
            stack: '總量',
            data: [120, 132, 101, 134, 90, 230, 210]
        },
        {
            name: '聯盟廣告',
            type: 'line',
            stack: '總量',
            data: [220, 182, 191, 234, 290, 330, 310]
        },
        {
            name: '視頻廣告',
            type: 'line',
            stack: '總量',
            data: [150, 232, 201, 154, 190, 330, 410]
        },
        {
            name: '直接訪問',
            type: 'line',
            stack: '總量',
            data: [320, 332, 301, 334, 390, 330, 320]
        },
        {
            name: '搜索引擎',
            type: 'line',
            stack: '總量',
            data: [820, 932, 901, 934, 1290, 1330, 1320]
        }
    ]
    };


    chart.on('legendselectchanged', function(obj) {
        var selected = obj.selected;
        var name = obj.name; // current clicked one
        // if all legends are selected, only enable clicked legend, others are toggled to false.
        // other situation, do what is default.

        if (selected != undefined) {

            if (isOnlyClickedOneIsUnSelected(name, selected)) {
            // all legend are selected except current clicked one
                onlyEnableCurrentSelectedLegend(name, selected, chart);
            }
        }

chart.setOption(options, true);


});

 function isOnlyClickedOneIsUnSelected(name, selected){
        var unSelectedCount = 0;
        for ( item in selected) {
            if (!selected.hasOwnProperty(item)) {
                continue;
            }

            if (selected[item] == false) {
                ++unSelectedCount;
            }
        }
        return unSelectedCount==1 && selected[name] == false;
}

function onlyEnableCurrentSelectedLegend(name, selected, echartInstance){
        var legend = [];
        for ( item in selected) {
            if (!selected.hasOwnProperty(item)) {
                continue;
            }
        legend.push({'name': item});


        echartInstance.dispatchAction({
            type: 'legendToggleSelect',
            batch: legend
        });
}