windows-phone-7 – 全景wp7 mvvm中的静态和动态全景项目

概念上,Panorama控件是一个ItemPresenter(它继承自ItemsPresenter),即您可以将ItemsSource绑定到包含重复您的PanoramaItems的项目的列表.

要渲染PanoramaItem,您必须提供Panorama.HeaderTemplate和Panorama.ItemTemplate的模板.模板内的DataContext是代表PanoramaItem的ViewModel.如果此ViewModel包含项目列表,您现在可以使用它来生成您正在寻找的ListBoxes.

以下是样本……

ViewModelLocator.cs

using GalaSoft.MvvmLight;

namespace WP7Test.ViewModel
{
    public class ViewModelLocator
    {
        private static MainViewModel _main;

        public ViewModelLocator()
        {
    if (ViewModelBase.IsInDesignModeStatic) {
        // Create design time services and viewmodels
    } else {
        // Create run time services and view models
    }
            _main = new MainViewModel();
        }

        [System.Diagnostics.CodeAnalysis.SuppressMessage("Microsoft.Performance","CA1822:MarkMembersAsStatic",Justification = "This non-static member is needed for data binding purposes.")]
        public MainViewModel Main
        {
            get
            {
                return _main;
            }
        }
    }
}

MainViewModel.cs

public class MainViewModel : ViewModelBase
{
    public MainViewModel()
    {
        this.Items = new ObservableCollection<ItemViewModel>();

        if (IsInDesignMode) {
            // Code runs in Blend --> create design time data.
        } else {
            // Code runs "for real"
        }
        this.LoadData();
    }

    #region [Items]

    public const string ItemsPropertyName = "Items";

    private ObservableCollection<ItemViewModel> _items = default(ObservableCollection<ItemViewModel>);

    public ObservableCollection<ItemViewModel> Items {
        get {
            return _items;
        }
        private set {
            if (_items == value) {
                return;
            }

            var oldValue = _items;
            _items = value;

            RaisePropertyChanged(ItemsPropertyName);
        }
    }

    #endregion

    private void LoadData() {
        this.Items.Add(new ItemViewModel() { LineOne = "runtime one",LineTwo = "Maecenas praesent accumsan bibendum",LineThree = "Facilisi faucibus habitant inceptos interdum lobortis nascetur pharetra placerat pulvinar sagittis senectus sociosqu" });
        this.Items.Add(new ItemViewModel() { LineOne = "runtime two",LineTwo = "Dictumst eleifend facilisi faucibus",LineThree = "Suscipit torquent ultrices vehicula volutpat maecenas praesent accumsan bibendum dictumst eleifend facilisi faucibus" });
        this.Items.Add(new ItemViewModel() { LineOne = "runtime three",LineTwo = "Habitant inceptos interdum lobortis",LineThree = "Habitant inceptos interdum lobortis nascetur pharetra placerat pulvinar sagittis senectus sociosqu suscipit torquent" });

        foreach (var item in Items) {
            for (int i = 0; i < 5; ++i)
                item.Items.Add(new ItemViewModel() { LineOne = "Item " + i,LineTwo = "Maecenas praesent accumsan bibendum" });
        }
    }
}

ItemViewModel.cs

public class ItemViewModel : ViewModelBase
{
    public ItemViewModel() {
        this.Items = new ObservableCollection<ItemViewModel>();

        if (IsInDesignMode) {
            // Code runs in Blend --> create design time data.
        } else {
            // Code runs "for real": Connect to service,etc...
        }
    }

    public override void Cleanup() {
        // Clean own resources if needed

        base.Cleanup();
    }

    #region [LineOne]

    public const string LineOnePropertyName = "LineOne";

    private string _lineOne = default(string);

    public string LineOne {
        get {
            return _lineOne;
        }

        set {
            if (_lineOne == value) {
                return;
            }

            var oldValue = _lineOne;
            _lineOne = value;
            RaisePropertyChanged(LineOnePropertyName);
        }
    }

    #endregion

    #region [LineTwo]

    public const string LineTwoPropertyName = "LineTwo";

    private string _lineTwo = default(string);

    public string LineTwo {
        get {
            return _lineTwo;
        }

        set {
            if (_lineTwo == value) {
                return;
            }

            var oldValue = _lineTwo;
            _lineTwo = value;

            RaisePropertyChanged(LineTwoPropertyName);
        }
    }

    #endregion

    #region [LineThree]

    public const string LineThreePropertyName = "LineThree";

    private string _lineThree = default(string);

    public string LineThree {
        get {
            return _lineThree;
        }

        set {
            if (_lineThree == value) {
                return;
            }

            var oldValue = _lineThree;
            _lineThree = value;
            RaisePropertyChanged(LineThreePropertyName);
        }
    }

    #endregion

    #region [Items]

    public const string ItemsPropertyName = "Items";

    private ObservableCollection<ItemViewModel> _items = default(ObservableCollection<ItemViewModel>);

    public ObservableCollection<ItemViewModel> Items {
        get {
            return _items;
        }
        private set {
            if (_items == value) {
                return;
            }

            var oldValue = _items;
            _items = value;
            RaisePropertyChanged(ItemsPropertyName);
        }
    }

    #endregion
}

MainPage.xaml中

<phone:PhoneApplicationPage 
    x:Class="WP7Test.MainPage"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    xmlns:phone="clr-namespace:Microsoft.Phone.Controls;assembly=Microsoft.Phone"
    xmlns:shell="clr-namespace:Microsoft.Phone.Shell;assembly=Microsoft.Phone"
    xmlns:controls="clr-namespace:Microsoft.Phone.Controls;assembly=Microsoft.Phone.Controls"
    xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
    xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006" 
    mc:Ignorable="d" d:DesignWidth="480" d:DesignHeight="800" 
    FontFamily="{StaticResource PhoneFontFamilyNormal}"
    FontSize="{StaticResource PhoneFontSizeNormal}"
    Foreground="{StaticResource PhoneForegroundBrush}"
    SupportedOrientations="Portrait"  Orientation="Portrait"
    shell:SystemTray.IsVisible="False">

    <!--LayoutRoot is the root grid where all page content is placed-->
    <Grid x:Name="LayoutRoot" Background="Transparent" DataContext="{Binding Main,Source={StaticResource Locator}}">
        <controls:Panorama Title="my application" ItemsSource="{Binding Items}">
            <controls:Panorama.Background>
                <ImageBrush ImageSource="PanoramaBackground.png"/>
            </controls:Panorama.Background>
            <controls:Panorama.HeaderTemplate>
                <DataTemplate>
                    <TextBlock Text="{Binding LineOne}"/>
                </DataTemplate>
            </controls:Panorama.HeaderTemplate>
            <controls:Panorama.ItemTemplate>
                <DataTemplate>
                    <StackPanel>
                        <Border BorderThickness="0,1" BorderBrush="White">
                            <TextBlock Text="{Binding LineTwo}" FontSize="28" TextWrapping="Wrap"/>
                        </Border>
                        <Border BorderThickness="0,1" Margin="0,20" BorderBrush="White">
                            <TextBlock Text="{Binding LineThree}" TextWrapping="Wrap"/>
                        </Border>
                        <ListBox ItemsSource="{Binding Items}">
                            <ListBox.ItemTemplate>
                                <DataTemplate>
                                    <StackPanel>
                                        <TextBlock Text="{Binding LineOne}" FontSize="24"/>
                                        <TextBlock Text="{Binding LineTwo}" FontSize="18" Margin="24,5"/>
                                    </StackPanel>
                                </DataTemplate>
                            </ListBox.ItemTemplate>
                        </ListBox>
                    </StackPanel>
                </DataTemplate>
            </controls:Panorama.ItemTemplate>
        </controls:Panorama>
    </Grid>
    <!--Panorama-based applications should not show an ApplicationBar-->
</phone:PhoneApplicationPage>

编辑 – 添加其他第一个面板

最后,我明白了你想要实现的目标！但是,您仍然无需执行任何代码！你只需要一个模板……对于这个Blend确实可以帮到你,因为它可以让你为一个现有的控件提取模板……好的,这里是变化.

首先,我向MainViewModel添加了一个新属性来显示一些数据：

#region [MainPageProperty]

public const string MainPagePropertyPropertyName = "MainPageProperty";
private string _mainPageProperty = "Facilisi faucibus habitant inceptos interdum lobortis nascetur pharetra placerat pulvinar sagittis senectus sociosqu";

public string MainPageProperty {
    get {
        return _mainPageProperty;
    }
    set {
        if (_mainPageProperty == value) {
            return;
        }

        _mainPageProperty = value;
        RaisePropertyChanged(MainPagePropertyPropertyName);
    }
}

#endregion

然后我使用Blend获取Panorama控件的模板并将其插入控件：Panorama元素.

<controls:Panorama.Template>
    <ControlTemplate TargetType="controls:Panorama">
        <Grid>
            <Grid.RowDefinitions>
                <RowDefinition Height="auto"/>
                <RowDefinition Height="*"/>
            </Grid.RowDefinitions>
            <controlsPrimitives:PanningBackgroundLayer x:Name="BackgroundLayer" HorizontalAlignment="Left" Grid.RowSpan="2">
                <Border x:Name="background" Background="{TemplateBinding Background}" CacheMode="BitmapCache"/>
            </controlsPrimitives:PanningBackgroundLayer>
            <controlsPrimitives:PanningTitleLayer x:Name="TitleLayer" CacheMode="BitmapCache" ContentTemplate="{TemplateBinding TitleTemplate}" Content="{TemplateBinding Title}" FontSize="187" FontFamily="{StaticResource PhoneFontFamilyLight}" HorizontalAlignment="Left" Margin="10,-76,9" Grid.Row="0"/>
            <controlsPrimitives:PanningLayer x:Name="ItemsLayer" HorizontalAlignment="Left" Grid.Row="1">
                <StackPanel Orientation="Horizontal">
                    <controls:PanoramaItem Header="Main panel" Width="432">
                        <TextBlock Text="{Binding ElementName=LayoutRoot,Path=DataContext.MainPageProperty}" TextWrapping="Wrap"/>
                    </controls:PanoramaItem>
                    <ItemsPresenter x:Name="items"/>
                </StackPanel>
            </controlsPrimitives:PanningLayer>
        </Grid>
    </ControlTemplate>
</controls:Panorama.Template>

这里有两个技巧,首先我插入一个StacPanel,允许在controlPrimitives下面有多个元素：PanningLayer,名称为ItemsPanel.在这个StackPanel中,我移动了ItemsPresenter并添加了另一个PanoramaItem.但有一件重要的事情是设置PanoramaItem的Width属性,否则面板将扩展到所需的房间.

另一个技巧是,为了访问DataContext,我必须在Binding中使用ElementName.

希望这能展示MVVM和模板的力量！