Angular states not showing amcharts after switching back to that state - angularjs

Question

I have two charts divs in html which I am able to display first time. but when my state changes and I come back to the state where I displayed charts. Then charts are not shown. I think I have to re-attach the dataProvider and render it again but i don't know how.
this is my controller
.controller('HomeCtrl', function ($location,$window) {
AmCharts.makeChart("chartdiv-pie", {
"type": "pie",
"theme": "light",
"dataProvider": [{
"title": "20%",
"value": 3852,
"color": "#18aa9f"
}, {
"title": "40%",
"value": 3899,
"color": "#e65548"
},
{
"title": "40%",
"value": 4899,
"color": "#e1e3e4"
}
],
"title": "AmCharts",
"color": "black",
"titleField": "title",
"valueField": "value",
"radius": "25%",
"outlineAlpha":0,
"innerRadius": "40%",
"balloonText": "[[value]]",
"labelText": "[[title]]",
"labelsEnabled": true,
"colorField": "color",
"labelText": "[[title]]",
"export": {
"enabled": true
},
});
var chart = AmCharts.makeChart( "chartdiv-male", {
"type": "serial",
"addClassNames": true,
"theme": "light",
"autoMargins": false,
"marginLeft": 30,
"marginRight": 8,
"marginTop": 10,
"marginBottom": 26,
"balloon": {
"adjustBorderColor": false,
"horizontalPadding": 10,
"verticalPadding": 8,
"color": "#ffffff"
},
"dataProvider": [ {
"year": "Pos",
"income": 30.1,
"color": "#FF0F00",
"expenses": 34.9,
}, {
"year": "Neg",
"income": 29.5,
"expenses": 31.1
}, {
"year": "Neu",
"income": 30.6,
"expenses": 28.2,
"dashLengthLine": 5,
"columnColor": 'green'
} ],
"valueAxes": [ {
"axisAlpha": 0,
"position": "left"
} ],
"startDuration": 1,
"graphs": [ {
"alphaField": "alpha",
"balloonText": "<span style='font-size:12px;'>[[title]] in [[category]]:<br><span style='font-size:20px;'>[[value]]</span> [[additional]]</span>",
"fillAlphas": 1,
"title": "Income",
"type": "column",
"valueField": "income",
"dashLengthField": "dashLengthColumn"
}, ],
"categoryField": "year",
"categoryAxis": {
"gridPosition": "start",
"axisAlpha": 0,
"tickLength": 0
},
"export": {
"enabled": true
}
} );
}
these are my states
.state('home.stats', {
url:'/stats',
templateUrl: 'views/stats.html',
controller: 'StatsCtrl',
controllerAs: 'stats'
})
.state('home.posts', {
url:'/posts',
templateUrl: 'views/posts.html',
controller: 'PostsCtrl',
controllerAs: 'posts'
});