I have a dashboard site in the works, and it makes use of SpringMVC, FusionCharts, and Bootstrap (to give an architectural overview). When I freshly start up the Tomcat server, the very first time I'm served the index page, a panel of buttons will not render properly. I get the correct number of white circles with question marks as made in the first of 3 javascript functions. If I refresh the page, the intended red and green results immediately come up, generated by the second script function.
As a preamble, the panel with buttons on it is correctly generated with the right count, correct names, correct HREFs and all else. The colors just do not change until the page is refreshed. Back when this project was first constructed, the data was being gathered via http request server-side. It was comparably slow to what is occurring now: loading the data from a file server-side and sending it through in the same format. The old way always produced the correct colors and icons after a 10-second wait. Now, the buttons just remain blank white until I refresh the page, and then I get the right results.
I believe this is just the result of two Javascript functions stepping on each other, even though I know JavaScript is single-threaded. If not, I'm stumped and lost.
Index.html
<!DOCTYPE html>
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta charset="utf-8" />
<meta name="viewport" content="width=device-width, initial-scale=1.0" />
<title>Free Bootstrap Admin Template : Dream</title>
<!-- Bootstrap Styles-->
<link href="css/bootstrap.min.css" rel="stylesheet" />
<!-- FontAwesome Styles-->
<link href="css/font-awesome.css" rel="stylesheet" />
<!-- Morris Chart Styles-->
<link href="js/morris/morris-0.4.3.min.css" rel="stylesheet" />
<!-- Custom Styles-->
<link href="css/custom-styles.css" rel="stylesheet" />
<!-- Google Fonts-->
<link href='https://fonts.googleapis.com/css?family=Open+Sans' rel='stylesheet' type='text/css' />
<script type="text/javascript" src="js/fusioncharts/core/fusioncharts.js"></script>
<script type="text/javascript" src="js/fusioncharts/themes/fusioncharts.theme.fint.js"></script>
</head>
<body>
...
<!-- this is where the button panel is correctly created on every load
but only correctly modified on the 2nd load and later -->
<div class="row"> <div id="AppStatusTable"></div> </div>
...
<script src="js/jquery-1.10.2.js"></script>
<!-- Bootstrap Js -->
<script src="js/bootstrap.min.js"></script>
<!-- Metis Menu Js -->
<script src="js/jquery.metisMenu.js"></script>
<!-- Morris Chart Js -->
<script src="js/morris/raphael-2.1.0.min.js"></script>
<script src="js/morris/morris.js"></script>
<!-- Custom Js -->
<!--
<script src="js/custom-scripts.js"></script> -->
<script>
$(document).ready(function(){
$.get("/buttoninfo", function(data, status) {
tableMaker(data, "AppStatusTable");
});
$.get("/appstatus", function(data, status) {
appStatus(data);
});
$.get("/stackstatus", function(data, status) {
stackUpdater(data);
});
});
</script>
</body>
These last 3 functions fill out the html of a panel to contain a dynamic number of buttons, modify the inner html of those buttons, and then update other panels. The third currently takes a while and always produces correct results. I don't suspect it is the issue.
dashboard.js
function templateLoader(appTag) {
//$.get('/app/' + appTag);
window.location = "/app/" + appTag;
}
function appStatus(data){
for(var i = 0; i < data.length; ++i) {
if(data[i][1] == "up"){
$("#" + data[i][0] + "-appcheck").removeClass("btn-default");
$("#" + data[i][0] + "-appcheck").addClass("btn-success");
$("#" + data[i][0] + "-appcheck-icon").removeClass("fa-exclamation-circle");
$("#" + data[i][0] + "-appcheck-icon").addClass("fa-check");
} else if(data[i][1] == "down"){
$("#" + data[i][0] + "-appcheck").removeClass("btn-default");
$("#" + data[i][0] + "-appcheck").addClass("btn-danger");
$("#" + data[i][0] + "-appcheck-icon").removeClass("fa-exclamation-circle");
$("#" + data[i][0] + "-appcheck-icon").addClass("fa-close");
}
}
}
function tableMaker(data, tableID) {
/* vars used below as the skeleton of the injected buttons*/
var i = 0, j = 0, colLimit = 12;
for(; i < data.length;){
for (var j = 0; j < colLimit && i < data.length; ++j, ++i) {
mytable += colStart + data[i][2] + titleEnd + '\n' + buttonStart + data[i][2] + buttonMiddle1 +
data[i][2] + buttonMiddle2 + data[i][2] + buttonMiddle3 + '><i id="' + data[i][2] +
buttonEnd + colEnd;
}
}
panel += mytable + panelEnd;
document.getElementById(tableID).innerHTML = panel;
}
function stackUpdater(data){
for(var i = 0; i < data.length; ++i){
var curStack = data[i][0];
for(var j = 1; j < data[i].length; j++) {
if(data[i][j] == null) {
break;
} else {
$("#" + curStack + j).removeClass("progress-bar-info");
if(data[i][j] == "up") {
$("#" + curStack + j).addClass("progress-bar-success");
} else {
$("#" + curStack + j).addClass("progress-bar-danger");
}
}
}
}
}
I understand browsers cache the results of javascript functions, but the third function is run on every refresh, so why wouldn't the first two be? And thus, why would the results of the second function only appear after refreshing?
What needs to be changed to make sure the buttons modify correctly the FIRST time this page is loaded?
UPDATE 1
After inserting alerts between the function calls, the rendering works on the first try, so what's the correct way to ensure synchronization without this?
Bottom of Index.html:
$(document).ready(function(){
$.get("/buttoninfo", function(data, status) {
tableMaker(data, "AppStatusTable");
});
alert("Button table made!");
$.get("/appstatus", function(data, status) {
appStatus(data);
});
alert("Button Data Updated!");
$.get("/stackstatus", function(data, status) {
stackUpdater(data);
});
alert("Stack Data Updated!");
});
</script>
