Question

我想将来自JSON的数据绑定到xamarin.forms中的ListView。我打了电话，我已经解析了JSON的数据。现在我无法理解在xamarin.forms中绑定数据的最佳方法。

JSON：

[{"Product":"XXX","Origins":[{"Origin":"ORI1","Details":[{"Seller":"Name","Seller_Rate":"256","Saller_QTY":"20","Buyer":"Name","Buyer_Rate":"256","Buyer_QTY":"20"},{"Seller":"Name","Seller_Rate":"256","Saller_QTY":"20","Buyer":"Name","Buyer_Rate":"256","Buyer_QTY":"20"}]},{"Origin":"ORI2","Details":[{"Seller":"Name","Seller_Rate":"256","Saller_QTY":"20","Buyer":"Name","Buyer_Rate":"256","Buyer_QTY":"20"},{"Seller":"Name","Seller_Rate":"256","Saller_QTY":"20","Buyer":"Name","Buyer_Rate":"256","Buyer_QTY":"20"}]}]},{"Product":"PQR","Origins":[{"Origin":"ABC","Details":[{"Seller":"Name","Seller_Rate":"256","Saller_QTY":"20","Buyer":"Name","Buyer_Rate":"256","Buyer_QTY":"20"},{"Seller":"Name","Seller_Rate":"256","Saller_QTY":"20","Buyer":"Name","Buyer_Rate":"256","Buyer_QTY":"20"}]},{"Origin":"PPP","Details":[{"Seller":"Name","Seller_Rate":"256","Saller_QTY":"20","Buyer":"Name","Buyer_Rate":"256","Buyer_QTY":"20"},{"Seller":"Name","Seller_Rate":"256","Saller_QTY":"20","Buyer":"Name","Buyer_Rate":"256","Buyer_QTY":"20"}]}]}]

这个JSON有产品，起源，产品等细节有很多起源和来源有不同的卖家，买家等。

我的来源是我的对象类：

public class Details
{
    public string Seller { get; set; }
    public string Seller_Rate { get; set; }
    public string Saller_QTY { get; set; }
    public string Buyer { get; set; }
    public string Buyer_Rate { get; set; }
    public string Buyer_QTY { get; set; }
}
public class Origins
{
    public string Origin { get; set; }
    public List<Details> Details { get; set; }
}
public class Products
{
    public List<Origins> Origins { get; set; }
    public string PRODUCT { get; set; }
}

我在此方法中解析它以测试结果：

public async Task<List<Products>> getProductsJson()
    {
        List<Products> root=null;
        Log.Debug("Login", "in get products");
        string responsejson = await client.GetStringAsync(Constants.url_getproducts);
        Log.Debug("Login", responsejson);
        try
        {
            root = JsonConvert.DeserializeObject<List<Products>>(responsejson);
            Log.Debug("Login",Convert.ToString(root.Count));
            for(int i=0;i<root.Count;i++)
            {
                Log.Debug("Login", "=============================");
                Log.Debug("Login", root[i].PRODUCT);
                for(int j=0;j<root[i].Origins.Count;j++)
                {
                    Log.Debug("Login","   "+root[i].Origins[j].Origin);
                    for(int k=0;k<root[i].Origins[j].Details.Count;k++)
                    {
                        Log.Debug("Login", "       Buy " + root[i].Origins[j].Details[k].Buyer+" BUY_QTY "+ root[i].Origins[j].Details[k].Buyer_QTY);

                    }
                }
                Log.Debug("Login", "=============================");
            }
            //Log.Debug("Login", root[0].PRODUCT);
            //Log.Debug("Login", root[0].Origins[0].Origin);
           // Log.Debug("Login", root[0].Origins[0].Details[0].Seller);
        }
        catch(Exception e)
        {
            Log.Debug("Login", e.Message);
            Log.Debug("Login", e.Source);
        }
        return root;
    }

正如我在这里打印日志一样，这个日志打印得恰到好处，每件事情都正常。我在xamal页面上将此方法称为：

async void GetProduct()
    {
        List<Products> result = await App.RestService.getProductsJson();
        list_data.ItemsSource = result;
    }

这里我将结果设置为 listview 。

在设计页面上：

<ContentPage.Content>
    <StackLayout VerticalOptions="FillAndExpand">
        <RelativeLayout VerticalOptions="FillAndExpand" HorizontalOptions="FillAndExpand">
        <StackLayout x:Name="logoStack">
            <Label x:Name="lbl_noInternet" HorizontalTextAlignment="Center" TextColor="Red" BackgroundColor="Black" />
        </StackLayout>
        <ListView x:Name="list_data"  HasUnevenRows="True">
            <ListView.ItemTemplate>
                <DataTemplate>
                    <!--<TextCell Text="{Binding Topic}" TextColor="Purple" Detail="{Binding Description}" DetailColor="Black"/>-->
                    <!--<ImageCell Text="{Binding Topic}" TextColor="Purple" Detail="{Binding Description}" DetailColor="Black" ImageSource="{Binding ImageSource}" />-->
                    <ViewCell>
                        <ViewCell.View>
                            <StackLayout Spacing="5" Orientation="Horizontal" HorizontalOptions="StartAndExpand" >
                                <Label Text="{Binding PRODUCT}" FontSize="20" FontAttributes="Bold" />
                                    <Label   Text="{Binding Origin}" FontSize="20" HorizontalOptions="End" HorizontalTextAlignment="End" />
                                </StackLayout>
                        </ViewCell.View>
                    </ViewCell>
                </DataTemplate>
            </ListView.ItemTemplate>
        </ListView>
        </RelativeLayout>
    </StackLayout>
</ContentPage.Content>

现在。我的代码工作正常，这意味着没有任何错误，但只显示PRODUCT，原始值没有显示在标签上。

现在我有3个问题。

因为origin是子数组如何将它绑定到listview中的标签？
这是实现这一目标的最佳方式。同样的方法还是以编程方式绑定它？

3.如果我们需要以编程方式绑定它意味着从.cs文件动态地如何做到这一点??

如何在Jamarin.forms

0 个答案: