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デザインビューにDog、Cat、およびHorseが表示されず、リストビューに3つの0とCommonNameが表示されている理由を理解できますか？このリストビューには、デザインビューでは機能していませんが、アプリだけで正しいデータが入力されています。コレクションアイテムがデザインビューに表示されない
ここ 
のViewModelコードのように見えるものです：
public class MainPageViewModel : ViewModelBase
{
public ObservableCollection<Animal> Animals { get; } = new ObservableCollection<Animal>();
public MainPageViewModel()
{
SQLiteConnection db = new SQLiteConnection("Animals.sqlite");
db.CreateTable<Animal>();
if (db.Table<Animal>().Count() == 0)
{
initCollection();
}
}
private void initCollection()
{
Animals.Clear();
Animals.Add(new Animal() { ID = 0, CommonName = "Dog" });
Animals.Add(new Animal() { ID = 1, CommonName = "Cat" });
Animals.Add(new Animal() { ID = 2, CommonName = "Horse" });
}
}
Animalクラス：XAMLで
public class Animal
{
[PrimaryKey]
public int ID { get; set; }
public string CommonName { get; set; }
}
がViewModelに
xmlns:vm="using:Module3_SQLite.ViewModels"
私は、その後のDataContext
<Page.DataContext>
<vm:MainPageViewModel />
</Page.DataContext>
を設定し、ここではリストビュー
<ListView x:Name="lvCollectionItems"
ItemsSource="{Binding Animals}"
HorizontalAlignment="Left"
Width="500" Height="200" Margin="0,10,0,10">
<ListView.ItemTemplate>
<DataTemplate>
<StackPanel Orientation="Horizontal">
<TextBlock Text="{Binding ID}" Margin="0,0,40,0" />
<TextBlock Text="{Binding CommonName}" />
</StackPanel>
</DataTemplate>
</ListView.ItemTemplate>
</ListView>
はここであなたがそれを必要とする場合は、完全なページXAMLだだ：
<Page x:Class="Module3_SQLite.Views.MainPage"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:Core="using:Microsoft.Xaml.Interactions.Core"
xmlns:Interactivity="using:Microsoft.Xaml.Interactivity"
xmlns:controls="using:Template10.Controls"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
xmlns:vm="using:Module3_SQLite.ViewModels"
xmlns:local="using:Module3_SQLite.Views"
mc:Ignorable="d" RequestedTheme="Dark">
<Page.DataContext>
<vm:MainPageViewModel />
</Page.DataContext>
<RelativePanel Background="{ThemeResource ApplicationPageBackgroundThemeBrush}">
<controls:PageHeader x:Name="pageHeader" Content="Main Page"
RelativePanel.AlignLeftWithPanel="True"
RelativePanel.AlignRightWithPanel="True"
RelativePanel.AlignTopWithPanel="True" />
<Grid
RelativePanel.Below="pageHeader"
RelativePanel.AlignLeftWithPanel="True"
RelativePanel.AlignRightWithPanel="True"
Padding="10">
<Grid.ColumnDefinitions>
<ColumnDefinition Width="2*" />
<ColumnDefinition />
</Grid.ColumnDefinitions>
<Grid.RowDefinitions>
<RowDefinition />
<RowDefinition />
</Grid.RowDefinitions>
<StackPanel Grid.Row="0">
<TextBlock Text="Collection Items" FontSize="{ThemeResource TextStyleExtraLargeFontSize}" />
<ListView x:Name="lvCollectionItems"
ItemsSource="{Binding Animals}"
HorizontalAlignment="Left"
Width="500" Height="200" Margin="0,10,0,10">
<ListView.ItemTemplate>
<DataTemplate>
<StackPanel Orientation="Horizontal">
<TextBlock Text="{Binding ID}" Margin="0,0,40,0" />
<TextBlock Text="{Binding CommonName}" />
</StackPanel>
</DataTemplate>
</ListView.ItemTemplate>
</ListView>
<StackPanel Orientation="Horizontal">
<Button x:Name="btnDeleteSelected" Content="Delete Selected" Margin="0,0,10,0" />
<Button x:Name="btnClearList" Content="Clear List" Margin="0,0,10,0" />
<Button x:Name="btnLoadFromDB" Content="Load From DB" Margin="0,0,10,0" />
<Button x:Name="btnResetCollection" Content="Reset Collection" />
</StackPanel>
</StackPanel>
<StackPanel Grid.Row="1">
<TextBlock Text="Database Items" FontSize="{ThemeResource TextStyleExtraLargeFontSize}" />
<ListView x:Name="lvDatabaseItems" Width="500" Height="200" Margin="0,10,0,10">
</ListView>
<StackPanel Orientation="Horizontal">
<Button x:Name="btnSaveToDB" Content="Save Collection to DB" Margin="0,0,10,0" />
<Button x:Name="btnDeleteSelectedFromDB" Content="Delete Selected From DB" Margin="0,0,10,0" />
<Button x:Name="btnDeleteAllFromDB" Content="Delete All From DB" Margin="0,0,10,0" />
</StackPanel>
</StackPanel>
<StackPanel Grid.Column="1" Grid.RowSpan="2" Orientation="Vertical">
<TextBlock Text="Edit Selected Item" FontSize="{ThemeResource TextStyleExtraLargeFontSize}" />
<StackPanel Orientation="Horizontal" Margin="0,10,0,10">
<TextBlock Text="Name:" FontSize="{ThemeResource TextStyleLargeFontSize}" Width="70"/>
<TextBox x:Name="txtbName" Width="200" />
</StackPanel>
<StackPanel Orientation="Horizontal" Margin="0,0,0,50">
<TextBlock Text="ID:" FontSize="{ThemeResource TextStyleLargeFontSize}" Width="70" />
<TextBox x:Name="txtbId" Width="200" />
</StackPanel>
<Button x:Name="btnSaveToCollection" Content="Save To Collection" Margin="0,0,0,10" />
<Button x:Name="btnInsertToDB" Content="Insert into DB" Margin="0,0,0,10" />
<Button x:Name="btnUpdateDB" Content="Update in DB" Margin="0,0,0,50" />
<TextBlock Text="Modify Collection" FontSize="{ThemeResource TextStyleExtraLargeFontSize}" />
<StackPanel Orientation="Horizontal" Margin="0,10,0,10" >
<TextBlock Text="Name:" Width="70" />
<TextBox x:Name="txtbItemNameCollection" Width="200"/>
</StackPanel>
<StackPanel Orientation="Horizontal" Margin="0,0,0,10">
<TextBlock Text="ID:" Width="70" />
<TextBox x:Name="txtbItemIDCollection" Width="200" />
</StackPanel>
<Button x:Name="btnUpdateCollection" Content="Update" HorizontalAlignment="Center" Width="115" />
</StackPanel>
</Grid>
</RelativePanel>
</Page>