π:0
As u can see, uβre executing new instance of Chart within window.onload function. This is the first reason.
Take a closer look β at the execution:
var ctx = document.getElementById("day-graph").getContext("2d");
You took the context over one canvas object, but in tabs you have three views. Sciprt cannot figure out that it should exec other charts.
U need to repeat the approach 3 times β the number of charts inside the tabs, for example:
//some previous code
var ctx = document.getElementById("week-graph").getContext("2d");
window.myLine = new Chart(ctx).Line(lineChartData, {
responsive: true
});
But for the optimalization purposes u should execucute the instance IF the tab in currently avaiable. And this thing u should do by yourself.
http://foundation.zurb.com/docs/components/tabs.html#callbacks