Question

Click here to see the screenshot of the code.

我正在制作一个列表应用程序，我正在为我再次打开应用程序时要加载的“列表”保存数组。 奇怪的是我在模拟器上工作但不在设备上工作。（参见截图了解）

In [1]: list1 =  ["A", "B" , "C"]

In [2]: list2 = ["E", "F", "G"]

In [3]: [a + ',' + b for a, b in zip(list1, list2)]
Out[3]: ['A,E', 'B,F', 'C,G']

就是它不断崩溃的那条线。

我试图更改它，因此它是一个可选值。但我找不到任何似乎有帮助的东西..

Answer 1

首先检查您的设备iOS版本是否为iOS 8或更高版本。如果小于该值，则在将值设置为NSUserDefaults后也使用synchronize（）。

你强行展开（使用！）你从Down Casting获得的可选值（使用as？）。

您还可以通过添加从NSUserDefaults获取的值的检查而不是nil来解决此崩溃，然后将其分配给您的feedCells var。

<!DOCTYPE html>
<html>
<head lang="en">
    <meta charset="UTF-8">
    <title>NG-Academy ::: AngularFire Products</title>
    <link rel="stylesheet" href="css/bootstrap.css">
    <script src="js/angular.js"></script>
    
    <!-- Firebase -->
    <script src="https://cdn.firebase.com/js/client/2.2.4/firebase.js"></script>
    <!-- AngularFire -->
    <script src="https://cdn.firebase.com/libs/angularfire/1.2.0/angularfire.min.js"></script>

    <script src="js/app.js"></script>

</head>
<body ng-app="myApp">
<div class="panel panel-primary" ng-controller="ProductsCtrl">
    <div class="panel-heading" style="font-size:large">
        Product Listttt
    </div>
    <form ng-submit="addFormSubmit()" ng-show="addFormShow">
        <input type="text" ng-model="productName" placeholder="Name" />
        <input type="text" ng-model="productCode" placeholder="Code" />
        <input type="text" ng-model="description" placeholder="Description" />
        <input type="text" ng-model="price" placeholder="Price" />
        <input type="submit" value="Add Product" class="btn btn-default btn-success" />
    </form>

    <form ng-submit="editFormSubmit()" ng-show="editFormShow">
        <input type="text" ng-model="productName" placeholder="Name" />
        <input type="text" ng-model="productCode" placeholder="Code" />
        <input type="text" ng-model="description" placeholder="Description" />
        <input type="text" ng-model="price" placeholder="Price" />
        <input type="submit" value="Edit Product" class="btn btn-default btn-warning" />
    </form>
    <div class="panel panel-body">
        <table class="table">
            <thead>
            <tr>
                <td>Product</td>
                <td>Code</td>
                <td>Description</td>
                <td>Price</td>
                <td>Actions</td>
            </tr>
            </thead>
            <tbody>
            <tr ng-repeat="product in products">
                <td>{{ product.productName}}</td>
                <td>{{ product.productCode }}</td>
                <td>{{ product.description }}</td>
                <td>{{ product.price | currency }}</td>
                <td>
                    <button class="btn btn-primary" ng-click="showProduct(product)" >Edit</button>&nbsp;
                    <button class="btn btn-danger" ng-click="deleteProduct(product)" >Delete</button>
                </td>
            </tr>
            </tbody>
        </table>
        <button class="btn btn-success" ng-click="showForm()" ng-hide="addFormShow">+</button>
        <button class="btn btn-warning" ng-click="hideForm()" ng-show="addFormShow">-</button>
    </div>
    {{products}}
</div>


<!-- <script src="https://www.gstatic.com/firebasejs/live/3.0/firebase.js"></script> -->
<script>
  // Initialize Firebase
  //REMOVED for security purposes
  //I have this on my version
</script>

</body>
</html>

或

将feedCells var设为可选项并删除“！”从收到错误的行的末尾开始。

let cells = NSUserDefaults.standardUserDefaults().objectForKey("feedCellsData") as? [String]
if cells != nil {
    feedCells = cells
}

（lldb）在设备上运行但在模拟器上运行时出错

1 个答案: