win 8 metro app c# multiple itemTemplate

问题:

I working on a metro app and I have situation. In one of my pages I used listview with a custom item template which displays an image and its name. now I have to use 2 item template if image is vertical I have to use another template with longer height. can there be 2 different templates in o listview ? I must change the template in .cs something like if the image is horizontal listview.ItemTemplate = 1 else if the image is vertical listvew.ItemTemplate =2 how Can I use this?

回答1:

First create a custom DataTemplateSelector class:

public class OrientationTemplateSelector : DataTemplateSelector
{
    protected override DataTemplate SelectTemplateCore(object item, DependencyObject container)
    {
        // cast item to your custom item class
        var customItem = item as CustomItem;
        if (customItem == null)
            return null;

        string templateName = String.Empty;
        if (customItem.Width > customItem.Height
        {
            // image is horizontal
            templateName = "HorizontalItemTemplate";
        }
        else
        {
            templateName = "VerticalItemTemplate";
        }

        object template = null;
        // find template in App.xaml
        Application.Current.Resources.TryGetValue(templateName, out template);
        return template as DataTemplate;
    }
}

Define your item templates as resources (in my case in App.xaml - make sure you search for them in the right place inside template selector):

<Application.Resources>
    <DataTemplate x:Key="HorizontalItemTemplate">
        <!-- item template for horizontal image -->
    </DataTemplate>
    <DataTemplate x:Key="VerticalItemTemplate">
        <!-- item template for vertical image -->
    </DataTemplate>
</Application.Resources>

Add the template selector as resource as well (at the ListView level as below or anywhere higher, i.e. page or application level):

<ListView.Resources>
    <local:OrientationTemplateSelector x:Key="OrientationTemplateSelector" />
</ListView.Resources>

Now you can set it as ItemTemplateSelector to your ListView:

<ListView ItemTemplateSelector="{StaticResource OrientationTemplateSelector}" ItemsSource="{Binding CustomItemsList}" />