Programmatically select an md-select option
<p>I have an angular-material <code>md-select</code> element with multiple selection which I define like this:</p>

<pre><code>&lt;md-select ng-model="selectedTypes"
           ng-change="typesChanged()"
           multiple
           ng-disabled="availableTypes.length == 0"&gt;
           &lt;md-option ng-repeat="type in availableTypes" ng-value="{{type}}"&gt;
              {{type.displayName}}
           &lt;/md-option&gt;
&lt;/md-select&gt;
</code></pre>

<p>During the load of the controller I load an array of available types from the server and then set the <code>selectedTypes</code> to <code>availableTypes[0]</code> (after the <code>availableTypes</code> is loaded) as follows:</p>

<pre><code>$scope.promise = Types.query(query, function (types) { // Types is a $resource
        $scope.availableTypes = types;
        $scope.selectedTypes = [$scope.availableTypes[0]];
});
</code></pre>

<p>Because <code>selectedTypes</code> is the model of the <code>md-select</code> directive, I expected that it will make the first selection option become selected. But it didn't work. I couldn't find in the documentation any way to programmatically select an element in the <code>md-select</code>.</p>