AngularJs Divs won't toggle using <select> - angularjs

Question

I have this in my view:
<div>
<select ng-model="chartType" ng-change="AnalyticsChartTypeChanged(chartType)"
ng-init="chartType='Data grid'">
<option value="Data grid">Data grid</option>
<option value="Histogram">Histogram</option>
</select>
{{chartType}}
<br>showAnalyticsDataGrid == {{showAnalyticsDataGrid}}
<br>showAnalyticsHistogram == {{showAnalyticsHistogram}}
<div ng-show="{{showAnalyticsDataGrid}}">
<p>Data grid goes here</p>
</div>
<div ng-show="{{showAnalyticsHistogram}}">
<p>Histogram goes here</p>
</div>
and the ng-chnage funtion is
$scope.AnalyticsChartTypeChanged = function(chartType)
{
switch (chartType)
{
case 'Data grid': $scope.showAnalyticsDataGrid = true;
$scope.showAnalyticsHistogram = false;
console.log('Show analytics data grid');
break;
case 'Histogram': $scope.showAnalyticsDataGrid = false;
$scope.showAnalyticsHistogram = true;
console.log('Show analytics histogram');
break;
}
}
When I alernately select each of the options, the debug text updates correcrly:
Data grid
showAnalyticsDataGrid == true
showAnalyticsHistogram == false
and
Histogram
showAnalyticsDataGrid == false
showAnalyticsHistogram == true
BUT, it constantly shows the Data grid DIV and never the Historgram DIV.
Obviouly I am making an extermely simple mistake, but I just can't see it :-(

Answer 1

With ng-show, you give it an expression and it evaluates it for you. What you're trying to do here is evaluating the expression by using the double curly braces{{}}, which doesn't make sense. If you simply remove those double curly braces and use the ng-show like this:
ng-show="showAnalyticsDataGrid"
it will work just fine.
Also, remember that those 2 variables aren't being initialized so when the view loads there will be no div shown by default, but you can fix that with an ng-init.
Here's a fiddle. http://jsfiddle.net/5DMjt/5248/

Answer 2

You don't use {{}} interpolation in ng-show. Like many other directives it directly evaluates expressions
Change
<div ng-show="{{showAnalyticsHistogram}}">
To
<div ng-show="showAnalyticsHistogram">