我使用dataLoader
从PHP/MySQL的后端在AmChart检索数据。 但是,生成简单的serial
条形图,但不知道渲染图的问题是什么,图形没有生成。加载数据不呈现图表
然后再次尝试使用ajax调用,我已经完成JSON
响应对象通过循环的重新解析,就像generateChartData()
一样,它是相同的数据。但仍然没有得到渲染。
这些选项,我传递给dataLoader
"dataLoader": {
"url": 'data.php',
"format": "json"
}
在Ajax调用我打电话chart.validateData()
,但是这是行不通的。能做些什么来解决这个问题?
设置async
ajax请求的选项false
发出警告并且不起作用。
这里是的js代码app.js
:
var chartData = [];
loadChartData();
function loadChartData() {
var time = new Date();
var ajax = new XMLHttpRequest();
ajax.onreadystatechange = function() {
if (ajax.readyState == 4 && ajax.status == 200) {
var cur = new Date();
var data = JSON.parse(ajax.responseText);
data.forEach(function(d, i) {
chartData.push({
date: d.date,
visits: parseInt(d.visits, 10)
});
});
// alert('Request Completed in '+ (cur - time)+ ' mili seconds');
console.log(chartData.length);
// chart.validateData();
}
};
ajax.open('GET', 'data.php', true);
ajax.setRequestHeader("Content-type", "application/json");
ajax.send();
}
var chart = AmCharts.makeChart("chartdiv", {
"type": "serial",
"theme": "light",
"marginRight": 80,
// "dataLoader": {
// "url": "data.php",
// "format": "json"
// }, this doesn't work too!
"dataProvider": chartData,
"dataDateFormat": "YYYY-MM-DD",
"valueAxes": [{
"position": "left",
"title": "Energy Generated"
}],
"graphs": [{
"id": "g1",
"fillAlphas": 0.4,
"valueField": "visits",
"balloonText": "<div style='margin:5px; font-size:19px;'><b>[[value]]kWh</b></div>"
}],
"chartScrollbar": {
"graph": "g1",
"scrollbarHeight": 80,
"backgroundAlpha": 0,
"selectedBackgroundAlpha": 0.1,
"selectedBackgroundColor": "#888888",
"graphFillAlpha": 0,
"graphLineAlpha": 0.5,
"selectedGraphFillAlpha": 0,
"selectedGraphLineAlpha": 1,
"autoGridCount": true,
"color": "#AAAAAA"
},
"chartCursor": {
"categoryBalloonDateFormat": "JJ:NN, DD MMMM",
"cursorPosition": "mouse"
},
"categoryField": "date",
"categoryAxis": {
"minPeriod": "mm",
"parseDates": true
},
});
// this method is called when chart is first inited as we listen for "dataUpdated" event
function zoomChart() {
// different zoom methods can be used - zoomToIndexes, zoomToDates, zoomToCategoryValues
chart.zoomToIndexes(chart.dataProvider.length - 250, chart.dataProvider.length - 100);
}
zoomChart();
这里是我的的PHP代码data.php
$link = new mysqli("localhost", "root", "", "test");
if ($link->connect_errno) {
die ("Failed to connect to MySQL: (" . $mysqli->connect_errno . ") " . $mysqli->connect_error);
}
// Fetch the data
$query = "SELECT *
FROM daily_visits
ORDER BY date ASC";
$result = $link->query($query);
// All good?
if (!$result) {
// Nope
$message = 'Invalid query: ' . $link->error . "\n";
$message .= 'Whole query: ' . $query;
die($message);
}
$data = array();
while ($row = $result->fetch_assoc()) {
$data[] = $row;
}
echo json_encode($data);
// Close the connection
mysqli_close($link);
,且返回json
看起来像
[{"date":"2016-09-03","visits":"16"},{"date":"2016-09-03","visits":"49"},...]
请发布您的完整代码和data.php返回的数据。否则,我们可以猜测可能是错的。 – martynasma
@martynasma更新了问题 –
@martynasma终于找到了一个解决方案。我必须将'date'字段的数据类型从'DATE'更改为'DATETIME',并且一切正常,但是我仍然看到生成了一些不指向任何值的垂直线。我想知道它是否可以删除。 –