Question

我是Caliburn Micro的新手，所以我确定我有一些简单易行的事情。在这里失踪。

我有一个顶级的Shell视图：

<Window x:Class="LotRunPlotGrid.ShellView"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:local="clr-namespace:LotRunPlotGrid.Views"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" 
        >
    <Grid>
        <local:LotRunPlotGridView />
    </Grid>
</Window>

及其相关的视图模型：

namespace LotRunPlotGrid
{
    public class ShellViewModel : IShell {}
}

然后我将用户控件定义为：

<UserControl x:Class="LotRunPlotGrid.Views.LotRunPlotGridView"
             xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
             xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
             xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006" 
             xmlns:converter="clr-namespace:LotRunPlotGrid.Converters"
             xmlns:d="http://schemas.microsoft.com/expression/blend/2008" 
             xmlns:vm="clr-namespace:LotRunPlotGrid.ViewModels"
             mc:Ignorable="d" 
             d:DesignHeight="300" d:DesignWidth="900"
             d:DataContext="{d:DesignInstance Type=vm:LotRunPlotGridViewModel, IsDesignTimeCreatable=True}">
    <UserControl.Resources>
        <converter:LotRunItemValueToColorConverter x:Key="ColorConverter"/>
        <Style x:Key="LotRunButtonStyle" TargetType="Button">
            <Setter Property="Width" Value="Auto"/>
            <Setter Property="Height" Value="{Binding ActualWidth, RelativeSource={RelativeSource Self}}"/>
            <Setter Property="BorderBrush" Value="Black"/>
            <Setter Property="BorderThickness" Value="2"/>
            <Setter Property="FontFamily" Value="Segoe UI"/>
            <Setter Property="FontSize" Value="20"/>
            <Setter Property="FontWeight" Value="Bold"/>
            <Setter Property="Foreground" Value="Black"/>
            <Setter Property="Content" Value="{Binding LotID}"/>
        </Style>
    </UserControl.Resources>
    <Grid>
        <Grid.RowDefinitions>
            <RowDefinition Height="Auto"/>
            <RowDefinition Height="Auto"/>
        </Grid.RowDefinitions>
        <TextBlock Grid.Row ="0" Text="Lot Run Plot Grid View" FontSize="20" FontFamily="Segoe UI"/>
        <ItemsControl Grid.Row="1" ItemsSource="{Binding LotRunItemsCollection}" Margin="0,0,-200,0" HorizontalAlignment="Left" Width="893">
            <ItemsControl.ItemsPanel>
                <ItemsPanelTemplate>
                    <UniformGrid Columns="10"/>
                </ItemsPanelTemplate>
            </ItemsControl.ItemsPanel>
            <ItemsControl.ItemTemplate>
                <DataTemplate>
                    <Button x:Name="LotRunItemButton" Style="{StaticResource LotRunButtonStyle}">
                        <Button.Background>
                            <MultiBinding Converter="{StaticResource ColorConverter}">
                                <Binding Path="LotRunDataDisplayMode" />
                                <Binding Path="LotRunItemValue"/>
                            </MultiBinding>
                        </Button.Background>
                    </Button>
                </DataTemplate>
            </ItemsControl.ItemTemplate>
        </ItemsControl>
    </Grid>
</UserControl>

及其相关的视图模型......

using Caliburn.Micro;
using System.Collections.ObjectModel;

namespace LotRunPlotGrid.ViewModels
{
    public class LotRunPlotGridViewModel : PropertyChangedBase
    {
        private ObservableCollection<LotRunItem> _lotRunItemsCollection = new ObservableCollection<LotRunItem>();
        public ObservableCollection<LotRunItem> LotRunItemsCollection
        {
            get { return _lotRunItemsCollection; }
            set { _lotRunItemsCollection = value; }
        }

        private int _numDisplayedColumns;
        public int NumDisplayedColumns
        {
            get { return _numDisplayedColumns; }
            set { _numDisplayedColumns = value; }
        }

        private int _numDisplayedRows;
        public int NumDisplayedRows
        {
            get { return _numDisplayedRows; }
            set { _numDisplayedRows = value; }
        }

        private int _lotRunDataDisplayMode;
        public int LotRunDataDisplayMode
        {
            get { return _lotRunDataDisplayMode; }
            set { _lotRunDataDisplayMode = value; }
        }


        public LotRunPlotGridViewModel()
        {
            LotRunItemsCollection.Add(new LotRunItem() { LotId = "Lot1", LotRunItemValue = "55", LotRunItemColor = "#FF05579" });
            LotRunItemsCollection.Add(new LotRunItem() { LotId = "Lot2", LotRunItemValue = "45", LotRunItemColor = "#FF05579" });
            LotRunItemsCollection.Add(new LotRunItem() { LotId = "Lot3", LotRunItemValue = "35", LotRunItemColor = "#FF05579" });
            LotRunItemsCollection.Add(new LotRunItem() { LotId = "Lot4", LotRunItemValue = "25", LotRunItemColor = "#FF05579" });
            LotRunItemsCollection.Add(new LotRunItem() { LotId = "Lot5", LotRunItemValue = "15", LotRunItemColor = "#FF05579" });
        }
    }
}

我遇到的问题是Items Control没有显示，因为我收到一条绑定错误，指出在ShellViewModel中找不到LotRunItemsCollection，如上所示，LotRunItemsCollection是LotRunPlotGridViewModel的成员。

那么我在这里错过了将LotRunPlotGridViewModel绑定到LotRunPlotGridView以便在正确的视图模型中找到LotRunItemsCollection的原因？

感谢您的帮助！

Answer 1

您收到该消息，因为该控件没有具有该属性名称的后备数据上下文。

在shell视图模型中创建一个属性，如下所示

namespace LotRunPlotGrid
{
    public class ShellViewModel : PropertyChangedBase, IShell {
        private LotRunPlotGridViewModel myGrid = new LotRunPlotGridViewModel();

        public LotRunPlotGridViewModel MyGrid {
            get { return myGrid; }
            set {
                myGrid = value;
                NotifyOfPropertyChanged();
            }
        }
    }
}

然后在视图中，您可以将用户控件命名为与属性名称

匹配

<Window x:Class="LotRunPlotGrid.ShellView"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:local="clr-namespace:LotRunPlotGrid.Views"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" 
        >
    <Grid>
        <local:LotRunPlotGridView x:Name="MyGrid" />
    </Grid>
</Window>

框架将按惯例将MyGrid属性绑定到local:LotRunPlotGridView作为其数据上下文。

如果您不想将用户控件直接绑定到shell，则框架足够智能，可以根据绑定的视图模型查找视图。

例如，如果shell具有以下

<Window x:Class="LotRunPlotGrid.ShellView"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" 
        >
    <Grid>
        <ContentControl x:Name="MyGrid" />
    </Grid>
</Window>

请注意已删除本地命名空间。绑定控件时的框架将注意到内容为空并使用命名约定搜索绑定属性的匹配视图。

Caliburn Micro用户控制数据上下文

1 个答案: