Update Totals in ng-repeat - angularjs

Question

Please take a look at this fiddle
What I'm trying to do is to calculate/update totals for each column inside a nested ng-repeat:
<tr ng-repeat="cust in customers">
<td>{{cust.name}}</td>
<td ng-repeat="book in books">
<p ng-init="index=getIndex(book.id, cust.id)"></p>
<input ng-model="qtys[index].qty">
</td>
</tr>
<tr>
<td>Total</td>
<td ng-repeat="book in books">
<input type=text value="{{sumQty(book.id)}}">
</td>
</tr>
I have 2 problems that I'm trying to solve:
The input boxes are now showing the correct values from my array. I'm trying to use ng-init to get the index from the array first based on the custId and bookId I pass in:
<p ng-init="index=getIndex(book.id, cust.id)"</p>
<input ng-model="qtys[index].qty">
I guess I'm not sure how to correctly bind the ng-model
The totals are not working. But I guess I need to solve the #1 problem before I can get this to work.
Please help. Thanks.

Answer 1

You got it almost right. The problem is in your getIndex method - the return that you do there does not return from getIndex, it just exits the function that you passed to forEach. If you modify it like this, it will work
$scope.getIndex = function(bookId, custId) {
var index = null;
angular.forEach($scope.qtys , function(item, idx) {
if (item.bookId == bookId && item.custId == custId) {
index = idx;
};
});
return index;
};
scope.sumQty seems unfinished (it takes a list as parameter, but you are passing an id to it). One way of fixing it would be to make it accept the id instead
$scope.sumQty = function(id) {
var total=0;
angular.forEach($scope.qtys , function(item){
if(item.bookId == id) {
total+= parseInt(item.qty);
}
});
return total;
}