火种卡的离子“跟踪”错误

Question

我两周前开始学习 Ionic，现在我正在创建一个小项目来练习。你可以从我的 Github 下载我的项目：https://github.com/KaanYildirim/ionicTest

我正在尝试使用由 ionic 团队本身创建的类似火种的卡片。 (https://github.com/driftyco/ionic-ion-tinder-cards)

我已经用“track by”表达式尝试了所有可能的解决方案，但我仍然收到这个错误：

错误：[ngRepeat:dupes] 不允许在转发器中重复。使用“track by”表达式指定唯一键。中继器：card.id 跟踪卡中的卡，重复键：未定义，重复值：未定义

我尝试使用“track by $index”和“track by card.id”修复此错误（每张卡在 .Json 文件中都有一个“id”属性），但没有成功。我猜我犯了一个小错误，找不到它。

有人可以帮我吗？谢谢

index.html:

 	  <td-cards>
      <td-card ng-repeat="card in cards track by card.id" on-destroy="cardDestroyed($index)" on-swipe="cardSwiped($index)">
        <div class="list card myCard">

          <!-- Card Header-->
          <div class="item topicDescription cardHeader">
             <p>{{card.topicDescription}}</p>
          </div>

          <!-- Card Body-->
          <div class="item item-body noBorder">
            <img class="full-image" src="{{card.image}}">
            <h3 class="cardTitle">{{card.title}}</h3>
            <p>{{card.summary}}</p>  
          </div>

          <!-- Card Footer-->
          <div class="item tabs tabs-secondary tabs-icon-left cardFooter">
             <a class="tab-item" ng-click="readMore($index)" href="#">
                 <i class="{{card.actionButtonIcon}}"></i>
                 {{card.actionButtonText}} {{card.type}} ( {{card.additionalInfo}} )
             </a>

             <a class="tab-item" ng-click="share($index)" href="#">
                <i class="icon ion-share"></i>
                Share
              </a>
          </div>
        </div>
      </td-card>
    </td-cards>

Json 文件：

{
  "articles": [
    {
      "id":1,
      "topicDescription": "Find a Idea",
      "image": "img/uber.jpg",
      "title": "Uber Lowers Fares In Over 100 Cities",
      "summary": "Uber is lowering prices in over 100 U.S. and Canadian cities, effective tomorrow. January is a slower month for the car service and the company says it is reducing fares in order to increase demand.",
      "link": "http://techcrunch.com/2016/01/08/uber-lowers-fares-in-over-100-cities/",
      "actionButtonIcon": "icon ion-ios-glasses-outline",
      "actionButtonText": "Read",
      "type":"Article",
      "additionalInfo": "3 min"
    },
    {
      "id":2,
      "topicDescription": "Test a Idea",
      "image": "img/lean.jpg",
      "title": "The Lean Startup",
      "summary": "Great book about startups and how to validate your idea without spending to much money and time.",
      "link": "http://www.amazon.de/Lean-Startup-Innovation-Successful-Businesses/dp/0670921602/ref=sr_1_2?ie=UTF8&qid=1452779528&sr=8-2&keywords=the+lean+startup",
      "actionButtonIcon": "icon ion-ios-bookmarks-outline",
      "actionButtonText": "Buy",
      "type":"Book",
      "additionalInfo": "Amazon"
    },
    {
      "id":3,
      "topicDescription": "Build",
      "image": "img/evernote.jpg",
      "title": "Note Taking App",
      "summary": "From short lists to lengthy research, no matter what form your writing takes, Evernote keeps you focused on moving those ideas from inspiration to completion.",
      "link": "https://evernote.com/?var=3",
      "actionButtonIcon": "icon ion-hammer",
      "actionButtonText": "Download",
      "type":"App",
      "additionalInfo": "App Store"
    },
    {
      "id":4,
      "topicDescription": "Measure",
      "image": "img/steve.jpg",
      "title": "Steve Blank: How to Build a Great Company",
      "summary": "Join Silicon Valley serial entrepreneur-turned-educator Blank in a lively discussion with Dan'l Lewin of Microsoft. This program will introduce best practices, lessons and tips that have swept the startup world, offering a wealth of proven advice and information for entrepreneurs of all stripes.",
      "link": "https://www.youtube.com/watch?v=1RTcXwJuCaU",
      "actionButtonIcon": "icon ion-ios-videocam-outline",
      "actionButtonText": "Watch",
      "type":"Video",
      "additionalInfo": "Youtube"
    },
    {
      "id":5,
      "topicDescription": "Find a Idea",
      "image": "img/uber.jpg",
      "title": "Uber Lowers Fares In Over 100 Cities",
      "summary": "Uber is lowering prices in over 100 U.S. and Canadian cities, effective tomorrow. January is a slower month for the car service and the company says it is reducing fares in order to increase demand.",
      "link": "http://techcrunch.com/2016/01/08/uber-lowers-fares-in-over-100-cities/",
      "actionButtonIcon": "icon ion-ios-glasses-outline",
      "actionButtonText": "Read",
      "type":"Article",
      "additionalInfo": "3 min"
    },
    {
      "id":6,
      "topicDescription": "Test a Idea",
      "image": "img/lean.jpg",
      "title": "The Lean Startup",
      "summary": "Great book about startups and how to validate your idea without spending to much money and time.",
      "link": "http://www.amazon.de/Lean-Startup-Innovation-Successful-Businesses/dp/0670921602/ref=sr_1_2?ie=UTF8&qid=1452779528&sr=8-2&keywords=the+lean+startup",
      "actionButtonIcon": "icon ion-ios-bookmarks-outline",
      "actionButtonText": "Buy",
      "type":"Book",
      "additionalInfo": "Amazon"
    },
    {
      "id":7,
      "topicDescription": "Build",
      "image": "img/evernote.jpg",
      "title": "Note Taking App",
      "summary": "From short lists to lengthy research, no matter what form your writing takes, Evernote keeps you focused on moving those ideas from inspiration to completion.",
      "link": "https://evernote.com/?var=3",
      "actionButtonIcon": "icon ion-hammer",
      "actionButtonText": "Download",
      "type":"App",
      "additionalInfo": "App Store"
    },
    {
      "id":8,
      "topicDescription": "Measure",
      "image": "img/steve.jpg",
      "title": "Steve Blank: How to Build a Great Company",
      "summary": "Join Silicon Valley serial entrepreneur-turned-educator Blank in a lively discussion with Dan'l Lewin of Microsoft. This program will introduce best practices, lessons and tips that have swept the startup world, offering a wealth of proven advice and information for entrepreneurs of all stripes.",
      "link": "https://www.youtube.com/watch?v=1RTcXwJuCaU",
      "actionButtonIcon": "icon ion-ios-videocam-outline",
      "actionButtonText": "Watch",
      "type":"Video",
      "additionalInfo": "Youtube"
    }
  ]
}

Answer 1

我检查了您的code。在您的 controllers.js 文件中，您通过手动将未定义的卡片添加到列表中来处理 cardSwiped 事件

$scope.cardSwiped = function(index) {
        var newCard = // new card data
         $scope.cards.push(newCard);
    };

这会导致你的卡片有多个未定义的元素，ng-repeat 将被强制处理为重复项。删除/修复该处理程序，事情应该可以工作。

顺便说一句，这段代码可以正常工作，因为 javascript 会将它们作为单行处理 var newCard = $scope.cards.push(newCard); 这意味着在函数结束时，您的 newCard 变量将具有卡片数组的新长度。