Importing jQuery function to Ember error "i is not defined"

I'm trying to implement the below jQuery calls to be used in my Ember Controller as actions.

jQuery (taken from http://ift.tt/2wFdpTK):

$('#checkAll').click(function(){
    for(i=0; i < chart.series.length; i++) {
        if(chart.series[i].selected == false){
            chart.series[i].select();
            showSeries.call(chart.series[i], {checked: true});
        }
    }
});
$('#uncheckAll').click(function(){
    for(i=0; i < chart.series.length; i++) {
        if(chart.series[i].selected == true){
            chart.series[i].select();
            showSeries.call(chart.series[i], {checked: false});
        }
    }
});

Implementation in Ember:

checkAll() {
  Ember.$('#checkAll').click(function(){
      for(i=0; i < chart.series.length; i++) {
          if(chart.series[i].selected == false){
              chart.series[i].select();
              showSeries.call(chart.series[i], {checked: true});
          }
      }
  });
},

uncheckAll() {
  Ember.$('#uncheckAll').click(function(){
      for(i=0; i < chart.series.length; i++) {
          if(chart.series[i].selected == true){
              chart.series[i].select();
              showSeries.call(chart.series[i], {checked: false});
          }
      }
  });
},

But I'm getting the error: "i is not defined" when I click the buttons:

  checkAll: function checkAll() {
    _ember['default'].$('#checkAll').click(function () {
      for (i = 0; i < chart.series.length; i++) { <== error here
        if (chart.series[i].selected == false) {
          chart.series[i].select();
          showSeries.call(chart.series[i], { checked: true });
        }
      }
    });
  },

What is wrong here?