Angular JS - How can i animate on model change?

问题

i'm trying to do a nice fadeout+fadein transition when the currentVertical changes. in knockout it was so simple but i can't figure it out here. please help.

the following code displays a UL list which is "bound" to a pricings array in the $scope.currentVertical when an LI element is clicked, the $scope.currentVertical is changed and the UL list updates accordingly. This works fine, but i would like the entire #container div to fade out and fadein when $scope.currentVertical is changed. Please help...

My html:

<body>
    <h1>Pricing Poll</h1>
    <div ng-controller="VerticalsController">
        <div id="container">
            <h2>{{currentVertical.title}}</h2>

            <ul>
                <li ng-repeat="pricing in currentVertical.pricings">
                    <a ng-click="currentVertical.selectPricing(pricing)">{{pricing.name}}</a>
                </li>
            </ul>
        </div>
    </div>
</body>

my javascript:

function VerticalsController($scope) {

  $scope.verticals = [
    {
        title:'internet',
        pricings: [
            {
                name: 'netvision',
                monthly: 23
            },
            {
                name: 'hot',
                monthly: 33
            },
            {
                name: '012',
                monthly: 28
            }
        ]
    },
    {
        title:'cellular', 
        pricings: [
            {
                name: 'cellcom',
                monthly: 20
            },
            {
                name: 'pelephone',
                monthly: 30
            },
            {
                name: 'orange',
                monthly: 25
            }
        ]
    },
    {
        title:'banks', 
        pricings: [
            {
                name: 'leumi',
                monthly: 20
            },
            {
                name: 'poalim',
                monthly: 30
            },
            {
                name: 'benleumi',
                monthly: 25
            }
        ]
    }];

    $scope.selected = [
    ];

    $scope.currentIndex = 0;
    $scope.currentVertical = $scope.verticals[0];

  $scope.selectPricing = function(pricing) {
    $scope.selected.push(pricing);
    $scope.currentIndex++;
    $scope.currentVertical = $scope.verticals[$scope.currentIndex];
  };

  /*$scope.remaining = function() {
    var count = 0;
    angular.forEach($scope.todos, function(todo) {
      count += todo.done ? 0 : 1;
    });
    return count;
  };*/
}

回答1:

You have to use custom or create directives to start advanced DOM manipulation like animations.

Here's a fiddle with the animation you requested, I use the visible variable on scope to trigger fading and the $timeout service to only change the selectedItem when fadeOut, it could be improved to pass a timeout and a callback as a directive option...

Fiddle: http://jsfiddle.net/g/Bs66R/1/

JS:

function VerticalsController($scope, $timeout) {

  $scope.verticals = [{
    title:'internet',
    pricings: [{
      name: 'netvision',
      monthly: 23
    },
    {
      name: 'hot',
      monthly: 33
    },
    {
      name: '012',
      monthly: 28
    }]
  },
  {
    title:'cellular',
    pricings: [{
      name: 'cellcom',
      monthly: 20
    },
    {
      name: 'pelephone',
      monthly: 30
    },
    {
      name: 'orange',
      monthly: 25
    }]
  },
  {
    title:'banks',
    pricings: [{
      name: 'leumi',
      monthly: 20
    },
    {
      name: 'poalim',
      monthly: 30
    },
    {
      name: 'benleumi',
      monthly: 25
    }]
  }];

  $scope.selected = [
  ];

  $scope.currentIndex = 0;
  $scope.currentVertical = $scope.verticals[0];

  $scope.selectPricing = function(pricing) {
    $scope.selected.push(pricing);
    $scope.currentIndex++;
    $scope.visible = false;

    $timeout(function(){
      $scope.currentVertical = $scope.verticals[$scope.currentIndex];
      $scope.visible = true;
    }, 1000);
  };

  $scope.visible = true;
}

var fadeToggleDirective = function() {
  return {
    link: function(scope, element, attrs) {
      scope.$watch(attrs.uiFadeToggle, function(val, oldVal) {
        if(val === oldVal) return; // Skip inital call
        // console.log('change');
        element[val ? 'fadeIn' : 'fadeOut'](1000);
      });
    }
  }
}

angular.module('app', []).controller('VerticalsController', VerticalsController).directive('uiFadeToggle', fadeToggleDirective);

angular.bootstrap(document.body, ['app']);    angular.bootstrap(document.body, ['app']);

HTML:

<h1>Pricing Poll</h1>
<div ng-controller="VerticalsController">
  <div id="container" ui-fade-toggle="visible">
    <h2>{{currentVertical.title}}</h2>

    <ul>
      <li ng-repeat="pricing in currentVertical.pricings">
        <a ng-click="selectPricing(pricing)">{{pricing.name}}</a>
      </li>
    </ul>
  </div>
</div>

回答2:

I recommend you use the new ngAnimate directive provided in the AngularJS Core.