角范围变量可在html页面上使用，但不能在控制器上使用？

Question

I wonder if anyone could help me I have created a new directive so I can filter a dropdown list while loading data from a webServer. It all works fine, and I can write the values to the HTML page using {{ myValue }} , and I can even use ng-model on an input, and it returns the value.

But for some reason, if I try to access the variable via the controller $scope.myValue is undefined ?

I have created a plunker (doesn't load data from webServer but just loads basic list values instead), but this seems to work, and my project doesn't, which I don't get as I have copied it from my project!.

If anyone has any ideas, I would really appreciate hearing them.

Plunker

On my page I have

<div search-dropdown text="myText" value="myValue"></div>

The directive is

<div class="btn-group searchDropdown">
    <button type="button" class="btn btn-default">
        <input search-dropdown-input type="text" placeholder="Enter name to search..." ng-model="filterText" ng-change="filter();" />
    </button>
    <button search-dropdown-toggle type="button" class="btn btn-default dropdown-toggle">
        <span class="caret"></span>
        <span class="sr-only">Split button!</span>
    </button>
    <ul class="dropdown-menu" role="menu">
        <li ng-repeat="item in items"><a href="javascript:void(0);" ng-click="selectItem($index);">{{ item.name }}</a></li>
    </ul>
</div>

Answer 1

You said you are loading it from webServer, could it be that you are trying to use that variable before the data from the back-end was assigned to it?

I would suggest to use something like:

$scope.$watch("myValue", function (newVal) {console.log(newVal);})

or:

$timeout(function () {console.log($scope.myValue);}, 5000)

The idea is to print the variable value after the back-end AJAX request finished. It it will print the correct value than you have to use the $watch function and to what you need to do with the variable after it has the expected value.

Answer 2

It appears that all is fine. The only difference was my angular version.

To fix my version I used an object to pass into my directive instead of two separate variables.

So now my directive properties are populated like so

Text="myObj.text" value="myObj.value"

I guess the "reference" to the variables was somehow lost?

Had a similar problem before and this was recommended. I only remembered after I posted on here. Hope this helps someone else