使用项目符号标签为值0的amcharts列系列设置最小宽度

编程问答 2022-06-07

问题描述

在以下示例中，我堆叠了带有项目符号标签的列系列。但正如您在示例中看到的那样，0值也很少。我正在尝试为序列设置一些最小宽度，以便即使值较小或0也可以看到项目符号标签。

您可以看到2017年的系列，它以0开头。但是标签并不完全可见。

/**
 * ---------------------------------------
 * This demo was created using amCharts 4.
 * 
 * For more information visit:
 * https://www.amcharts.com/
 * 
 * Documentation is available at:
 * https://www.amcharts.com/docs/v4/
 * ---------------------------------------
 */

// Themes begin
am4core.useTheme(am4themes_animated);
// Themes end

// Create chart instance
var chart = am4core.create("chartdiv",am4charts.XYChart);

// Add data
chart.data = [{
  "year": "2016","europe": 1.5,"namerica": 1.5,"asia": 1.1,"lamerica": 0.3,"meast": 0.2,"africa": 0
},{
  "year": "2017","europe": 0,"namerica": 1.7,"asia": 1.2,"meast": 0.3,"africa": 0.1
},{
  "year": "2018","europe": 1.8,"namerica": 1.9,"asia": 0,"africa": 0.1
}];

chart.legend = new am4charts.Legend();
chart.legend.position = "right";

// Create axes
var categoryAxis = chart.yAxes.push(new am4charts.CategoryAxis());
categoryAxis.datafields.category = "year";
categoryAxis.renderer.grid.template.opacity = 0;

var valueAxis = chart.xAxes.push(new am4charts.ValueAxis());
valueAxis.min = 0;
valueAxis.renderer.grid.template.opacity = 0;
valueAxis.renderer.ticks.template.strokeOpacity = 0.5;
valueAxis.renderer.ticks.template.stroke = am4core.color("#495C43");
valueAxis.renderer.ticks.template.length = 10;
valueAxis.renderer.line.strokeOpacity = 0.5;
valueAxis.renderer.baseGrid.disabled = true;
valueAxis.renderer.minGriddistance = 40;

// Create series
function createSeries(field,name) {
  var series = chart.series.push(new am4charts.ColumnSeries());
  series.datafields.valueX = field;
  series.datafields.categoryY = "year";
  series.stacked = true;
  series.name = name;
  
  series.minWidth = `100px`;
  
  var labelBullet = series.bullets.push(new am4charts.LabelBullet());
  labelBullet.locationX = 0.5;
  labelBullet.label.text = "{valueX}";
  labelBullet.label.fill = am4core.color("#fff");
}

createSeries("europe","Europe");
createSeries("namerica","north America");
createSeries("asia","Asia");
createSeries("lamerica","Latin America");
createSeries("meast","Middle East");
createSeries("africa","Africa");

chart.legend.position = 'bottom';
body {
  font-family: -apple-system,BlinkMacSystemFont,"Segoe UI",Roboto,Helvetica,Arial,sans-serif,"Apple Color Emoji","Segoe UI Emoji","Segoe UI Symbol";
}

#chartdiv {
  width: 100%;
  height: 500px;
}
<script src="https://cdn.amcharts.com/lib/4/core.js"></script>
<script src="https://cdn.amcharts.com/lib/4/charts.js"></script>
<script src="https://cdn.amcharts.com/lib/4/themes/animated.js"></script>
<div id="chartdiv"></div>

解决方法

由于列大小与其数据直接相关，因此无法指定最小宽度/高度（取决于轴旋转）。设置最小尺寸会错误地代表图表中的列值。

更好的解决方案是通过在标签项目符号上将hideOversized设置为true来隐藏不合适的标签，并使用工具提示代替图表光标。

am4core.useTheme(am4themes_animated);

var chart = am4core.create("chartdiv",am4charts.XYChart);

// Add data
chart.data = [{
  "year": "2016","europe": 1.5,"namerica": 1.5,"asia": 1.1,"lamerica": 0.3,"meast": 0.2,"africa": 0
},{
  "year": "2017","europe": 0,"namerica": 1.7,"asia": 1.2,"meast": 0.3,"africa": 0.1
},{
  "year": "2018","europe": 1.8,"namerica": 1.9,"asia": 0,"africa": 0.1
}];

chart.legend = new am4charts.Legend();
chart.legend.position = "right";

// Create axes
var categoryAxis = chart.yAxes.push(new am4charts.CategoryAxis());
categoryAxis.dataFields.category = "year";
categoryAxis.renderer.grid.template.opacity = 0;

var valueAxis = chart.xAxes.push(new am4charts.ValueAxis());
valueAxis.min = 0;
valueAxis.renderer.grid.template.opacity = 0;
valueAxis.renderer.ticks.template.strokeOpacity = 0.5;
valueAxis.renderer.ticks.template.stroke = am4core.color("#495C43");
valueAxis.renderer.ticks.template.length = 10;
valueAxis.renderer.line.strokeOpacity = 0.5;
valueAxis.renderer.baseGrid.disabled = true;
valueAxis.renderer.minGridDistance = 40;

// Create series
function createSeries(field,name) {
  var series = chart.series.push(new am4charts.ColumnSeries());
  series.dataFields.valueX = field;
  series.dataFields.categoryY = "year";
  series.stacked = true;
  series.name = name;
  series.tooltipText = "{name}: {valueX}";
  
  var labelBullet = series.bullets.push(new am4charts.LabelBullet());
  labelBullet.label.hideOversized = true;
  labelBullet.locationX = 0.5;
  labelBullet.label.text = "{valueX}";
  labelBullet.label.fill = am4core.color("#fff");
}

createSeries("europe","Europe");
createSeries("namerica","North America");
createSeries("asia","Asia");
createSeries("lamerica","Latin America");
createSeries("meast","Middle East");
createSeries("africa","Africa");

chart.legend.position = 'bottom';
chart.cursor = new am4charts.XYCursor();
body {
  font-family: -apple-system,BlinkMacSystemFont,"Segoe UI",Roboto,Helvetica,Arial,sans-serif,"Apple Color Emoji","Segoe UI Emoji","Segoe UI Symbol";
}

#chartdiv {
  width: 100%;
  height: 500px;
}
<script src="https://cdn.amcharts.com/lib/4/core.js"></script>
<script src="https://cdn.amcharts.com/lib/4/charts.js"></script>
<script src="https://cdn.amcharts.com/lib/4/themes/animated.js"></script>
<div id="chartdiv"></div>

,

以上答案提供了不同的方法，或者您可以像这样稍微移动标签。

/**
 * ---------------------------------------
 * This demo was created using amCharts 4.
 * 
 * For more information visit:
 * https://www.amcharts.com/
 * 
 * Documentation is available at:
 * https://www.amcharts.com/docs/v4/
 * ---------------------------------------
 */

// Themes begin
am4core.useTheme(am4themes_animated);
// Themes end

// Create chart instance
var chart = am4core.create("chartdiv",name) {
  var series = chart.series.push(new am4charts.ColumnSeries());
  series.dataFields.valueX = field;
  series.dataFields.categoryY = "year";
  series.stacked = true;
  series.name = name;
  
  series.minWidth = `100px`;
  
  var labelBullet = series.bullets.push(new am4charts.LabelBullet());
  labelBullet.locationX = 0.5;
  labelBullet.label.text = "{valueX}";
  labelBullet.label.fill = am4core.color("#fff");
  labelBullet.label.x= 4;
}

createSeries("europe","Africa");

chart.legend.position = 'bottom';
body {
  font-family: -apple-system,"Segoe UI Symbol";
}

#chartdiv {
  width: 100%;
  height: 500px;
}
<script src="https://cdn.amcharts.com/lib/4/core.js"></script>
<script src="https://cdn.amcharts.com/lib/4/charts.js"></script>
<script src="https://cdn.amcharts.com/lib/4/themes/animated.js"></script>
<div id="chartdiv"></div>

amchartsamcharts4chartsjavascript