chartjs在鼠标悬停时非常快速地调整(闪烁)

Question

我在基于引导程序的页面中有一个图表,我试图在页面调整大小时调整它的大小,以跟踪响应式设计的变化.所以我有这段代码:

function redrawChart() {
    var w = $("#chart_container").width();
    var c = document.getElementById("chart_canvas");
    c.width = w;
    c.height = w/2;
    $("#chart_canvas").css("width", w);
    $("#chart_canvas").css("height", w/2);

    var chart_canvas = document.getElementById("chart_canvas").getContext("2d");
    var line_chart= new Chart(chart_canvas).Line(data, options);
};

redrawChart();

var resizeTimer; 

$(window).resize(function() {
    clearTimeout(resizeTimer);
    resizeTimer = setTimeout(redrawChart, 250);
});

因此,在加载页面时调用一次redrawChart,然后调整每个页面的大小.

症状:当页面加载时,只要没有调整大小,一切都会完美运行.调整大小后,图表会闪烁,当鼠标悬停在图表上时会非常快速地调整大小.

这可能有什么不对？

Answer 1

在同一画布上重新创建图表之前,需要销毁图表.所以你可以像这样编辑你的重绘:

 //declare outside so it can be resued and checked
 var line_chart;

function redrawChart() {
    //if we already have a chart destroy it then carry on as normal
    if(line_chart)
    {
            line_chart.destroy();
    }
    var w = $("#chart_container").width();
    var c = document.getElementById("canvas");
    c.width = w;
    c.height = w/2;
    $("#chart_canvas").css("width", w);
    $("#chart_canvas").css("height", w/2);

    var chart_canvas = document.getElementById("canvas").getContext("2d");
    line_chart= new Chart(chart_canvas).Bar(barChartData);
};

这是一个小提琴,所以你可以实际重新调整运行窗口的大小,看看它是否有效http://fiddle.jshell.net/leighking2/4apqqjL0/

这是你喜欢的片段

var randomScalingFactor = function () {
    return Math.round(Math.random() * 100)
};

var barChartData = {
    labels: ["January", "February", "March", "April", "May", "June", "July"],
    datasets: [{
        fillColor: "rgba(220,220,220,0.5)",
        strokeColor: "rgba(220,220,220,0.8)",
        highlightFill: "rgba(220,220,220,0.75)",
        highlightStroke: "rgba(220,220,220,1)",
        data: [randomScalingFactor(), randomScalingFactor(), randomScalingFactor(), randomScalingFactor(), randomScalingFactor(), randomScalingFactor(), randomScalingFactor()]
    }, {
        fillColor: "rgba(151,187,205,0.5)",
        strokeColor: "rgba(151,187,205,0.8)",
        highlightFill: "rgba(151,187,205,0.75)",
        highlightStroke: "rgba(151,187,205,1)",
        data: [randomScalingFactor(), randomScalingFactor(), randomScalingFactor(), randomScalingFactor(), randomScalingFactor(), randomScalingFactor(), randomScalingFactor()]
    }, {
        fillColor: "rgba(15,18,20,0.5)",
        strokeColor: "rgba(15,18,20,0.8)",
        highlightFill: "rgba(15,18,20,0.75)",
        highlightStroke: "rgba(15,18,20,1)",
        data: [randomScalingFactor(), randomScalingFactor(), randomScalingFactor(), randomScalingFactor(), randomScalingFactor(), randomScalingFactor(), randomScalingFactor()]
    }]

}


 var line_chart;

function redrawChart() {
    if(line_chart)
    {
            line_chart.destroy();
    }
    var w = $("#chart_container").width();
    var c = document.getElementById("canvas");
    c.width = w;
    c.height = w/2;
    $("#chart_canvas").css("width", w);
    $("#chart_canvas").css("height", w/2);

    var chart_canvas = document.getElementById("canvas").getContext("2d");
    line_chart= new Chart(chart_canvas).Bar(barChartData);
};

redrawChart();

var resizeTimer; 

$(window).resize(function() {
    clearTimeout(resizeTimer);
    resizeTimer = setTimeout(redrawChart, 250);
});

<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/Chart.js/1.0.1/Chart.js"></script>
<div id="chart_container"style="width: 50%">
    <canvas id="canvas" height="450" width="600"></canvas>
</div>