Binding to a specific object in array with AngularJS - angularjs

Question

I have a collection of rooms in my $scope, with the structure:
$scope.model.rooms = [
{ RoomNumber: 1, Type: 'Single'},
{ RoomNumber: 3, Type: 'Single'},
{ RoomNumber: 5, Type: 'Double'},
{ RoomNumber: 6, Type: 'Single'},
{ RoomNumber: 12, Type: 'Double'}
];
I then create a 5x5 grid on my view as follows, and want to have the correct room type selected on the drop down, but I don't know how to do this binding properly.
<div data-ng-repeat="y in [1, 2, 3, 4, 5]" class="hotelRooms">
<div data-ng-repeat="x in [1, 2, 3, 4, 5]">
<h6>
Room #{{(y-1)*5+x}}
<select id="binType{{(y-1)*5+x}}" data-ng-model="model.rooms[/*WHAT DO I PUT HERE?*/].Type" data-ng-change="setRoomType((y-1)*5+x)">
<option value="Single">Single</option>
<option value="Double">Double</option>
</select>
</h6>
<div id="bin{{(y-1)*5+x}}" data-droppable="{{(y-1)*5+x}}" data-drop="addToRoom">
<div id="{{p.Id}}" data-draggable="" data-ng-repeat="p in model.participants | filter:{RoomNumber:(y-1)*5+x}">{{p.Name}}</div>
</div>
</div>
</div>
The array index isn't the same as the RoomNumber property.

Answer 1

I find it much more intuitive if you put all of your behavior into your controller. Your view just binds to those behaviors (a la MVVM). You get more control over your code this way and aren't at the mercy of {{binding syntax}} and its limitations.
I removed the drag and drop stuff, but here's how I got it to work. Notice you don't need the ngChange directive in the select because this way it's bound right to the room model Type property. So they stay in sync when you change it.
Here's a fiddle with the working code, or just see below: http://jsfiddle.net/854wk/7/
Controller:
function MyController($scope) {
$scope.calcBin = calcBin;
$scope.getRoomByBin = getRoomByBin;
function calcBin(row, col) {
return ((row - 1) * 5) + col;
};
function getRoomByBin(row, col) {
var bin = calcBin(row, col);
var foundRoom;
$scope.model.rooms.some(function(room) {
if (room.RoomNumber === bin)
{
foundRoom = room;
return true; // break
}
});
return foundRoom;
}
}
View:
<div ng-app>
<div ng-controller="MyController">
<div data-ng-repeat="y in [1, 2, 3, 4, 5]"
class="hotelRooms">
<div data-ng-repeat="x in [1, 2, 3, 4, 5]">
<h6>
Room #{{calcBin(y,x)}}
<select id="binType{{calcBin(y,x)}}"
data-ng-model="getRoomByBin(y,x).Type" >
<option value="Single">Single</option>
<option value="Double">Double</option>
</select>
Room Type is: {{getRoomByBin(y,x).Type}}
</h6>
</div>
</div>
</div>