我希望有人能看到一双新鲜的眼睛，因为我看不到它。
我得到的错误是：System.InvalidOperationException：'在使用ItemsSource之前，Items集合必须为空。'
StackOverflow上的其他文章建议密切关注GridViewColumn和GridViewColumn.CellTemplate以及DataTemplate。它看起来似乎正确，希望您能看到我看不到的东西。
下面是C＃。上面提供的错误消息实际上指向下面的.ItemsSource-但我需要这样做：
private void RefreshList()
{
lstoList.ItemsSource = oList;
oList.Clear();
foreach (var offVar in db.O)
{
oList.Add(offVar);
}
lstoList.Items.Refresh();
}
下面是xaml：
<Page x:Class="LApplication.p"
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:d="http://schemas.microsoft.com/expression/blend/2008"
xmlns:local="clr-namespace:LApplication"
mc:Ignorable="d"
Loaded="Page_Loaded"
d:DesignHeight="500" d:DesignWidth="900"
Title="p">
<Grid>
<Grid.RowDefinitions>
<RowDefinition Height="200" />
<RowDefinition Height="*" />
<RowDefinition Height="*" />
</Grid.RowDefinitions>
<!--<StackPanel>-->
<TabControl Height="200">
<TabItem Header="L Applicants">
<Grid>
<Grid.ColumnDefinitions>
</Grid.ColumnDefinitions>
<Grid.RowDefinitions>
<RowDefinition Height="50*"/>
<RowDefinition Height="*"/>
<RowDefinition Height="*"/>
<RowDefinition Height="*"/>
</Grid.RowDefinitions>
<ListView Name="lstoList" Grid.Row="0" Grid.ColumnSpan="1" SelectionChanged="lstoList_SelectionChanged">
<ListView.View>
<GridView>
<GridViewColumn Header="UserId" Width="120" >
<GridViewColumn.CellTemplate>
<DataTemplate>
<TextBlock HorizontalAlignment="Stretch" TextWrapping="Wrap" Text="{Binding UserId}" ></TextBlock>
</DataTemplate>
</GridViewColumn.CellTemplate>
</GridViewColumn>
<GridViewColumn Header="QuoteId" Width="120" >
<GridViewColumn.CellTemplate>
<DataTemplate>
<TextBlock HorizontalAlignment="Stretch" TextWrapping="Wrap" Text="{Binding QuoteId}"></TextBlock>
</DataTemplate>
</GridViewColumn.CellTemplate>
</GridViewColumn>
<GridViewColumn Header="oAmount" Width="120" >
<GridViewColumn.CellTemplate>
<DataTemplate>
<TextBlock HorizontalAlignment="Stretch" TextWrapping="Wrap" Text="{Binding oAmount}"></TextBlock>
</DataTemplate>
</GridViewColumn.CellTemplate>
</GridViewColumn>
<GridViewColumn Header="Term" Width="120" >
<GridViewColumn.CellTemplate>
<DataTemplate>
<TextBlock HorizontalAlignment="Stretch" TextWrapping="Wrap" Text="{Binding Term}" ></TextBlock>
</DataTemplate>
</GridViewColumn.CellTemplate>
</GridViewColumn>
<GridViewColumn Header="IRate" Width="120" >
<GridViewColumn.CellTemplate>
<DataTemplate>
<TextBlock HorizontalAlignment="Stretch" TextWrapping="Wrap" Text="{Binding IRate}"></TextBlock>
</DataTemplate>
</GridViewColumn.CellTemplate>
</GridViewColumn>
<GridViewColumn Header="FirstName" Width="120" >
<GridViewColumn.CellTemplate>
<DataTemplate>
<TextBlock HorizontalAlignment="Stretch" TextWrapping="Wrap" Text="{Binding FirstName}"></TextBlock>
</DataTemplate>
</GridViewColumn.CellTemplate>
</GridViewColumn>
<GridViewColumn Header="LastName" Width="120" >
<GridViewColumn.CellTemplate>
<DataTemplate>
<TextBlock HorizontalAlignment="Stretch" TextWrapping="Wrap" Text="{Binding LastName}"></TextBlock>
</DataTemplate>
</GridViewColumn.CellTemplate>
</GridViewColumn>
<GridViewColumn Header="datetime" Width="120" >
<GridViewColumn.CellTemplate>
<DataTemplate>
<TextBlock HorizontalAlignment="Stretch" TextWrapping="Wrap" Text="{Binding datetime}"></TextBlock>
</DataTemplate>
</GridViewColumn.CellTemplate>
</GridViewColumn>
<GridViewColumn Header="oStatusId" Width="120" >
<GridViewColumn.CellTemplate>
<DataTemplate>
<TextBlock HorizontalAlignment="Stretch" TextWrapping="Wrap" Text="{Binding oStatusId}"></TextBlock>
</DataTemplate>
</GridViewColumn.CellTemplate>
</GridViewColumn>
<GridViewColumn Header="pName" Width="120" >
<GridViewColumn.CellTemplate>
<DataTemplate>
<TextBlock HorizontalAlignment="Stretch" TextWrapping="Wrap" Text="{Binding pName}"></TextBlock>
</DataTemplate>
</GridViewColumn.CellTemplate>
</GridViewColumn>
<GridViewColumn Header="CompanyReg" Width="120" >
<GridViewColumn.CellTemplate>
<DataTemplate>
<TextBlock HorizontalAlignment="Stretch" TextWrapping="Wrap" Text="{Binding CompanyReg}"></TextBlock>
</DataTemplate>
</GridViewColumn.CellTemplate>
</GridViewColumn>
</GridView>
</ListView.View>
<!--Enables right click-->
<ListView.ContextMenu>
<ContextMenu Name="UserListOverview" IsEnabled="True">
<ContextMenu.Items>
<MenuItem Header="Add New o" Name="submenuAddo" IsEnabled="True" Click="submenuAdd_Click">
<MenuItem.Icon>
<Image Source="Images/add.png" Stretch="Uniform"></Image>
</MenuItem.Icon>
</MenuItem>
<MenuItem Header="Update Selected o" Name="submenuModifyo" IsEnabled="True" >
<MenuItem.Icon>
<Image Source="Images/update.png" Stretch="Uniform"></Image>
</MenuItem.Icon>
</MenuItem>
<MenuItem Header="Remove Selected o" Name="submenuDeleteo" IsEnabled="True">
<MenuItem.Icon>
<Image Source="Images/remove.png" Stretch="Uniform"></Image>
</MenuItem.Icon>
</MenuItem>
</ContextMenu.Items>
</ContextMenu>
</ListView.ContextMenu>
<ScrollBar x:Name="scrollBar" Height="100" Width="500"/>
</ListView>
</Grid>
</TabItem>
<TabItem Header="p Logs">
<Grid>
<Grid.ColumnDefinitions>
<ColumnDefinition Width="1200*"/>
<ColumnDefinition Width="*"/>
<ColumnDefinition Width="*"/>
</Grid.ColumnDefinitions>
<Grid.RowDefinitions>
<RowDefinition Height="400"/>
<RowDefinition Height="50*"/>
</Grid.RowDefinitions>
<ListView Name="lstpList" Grid.Row="0" Grid.ColumnSpan="2">
<ListView.View>
<GridView>
<GridViewColumn Header="UserId" Width="120" >
<GridViewColumn.CellTemplate>
<DataTemplate>
<TextBlock HorizontalAlignment="Stretch" TextWrapping="Wrap" Text="{Binding UserId}" ></TextBlock>
</DataTemplate>
</GridViewColumn.CellTemplate>
</GridViewColumn>
<GridViewColumn Header="datetime" Width="120" >
<GridViewColumn.CellTemplate>
<DataTemplate>
<TextBlock HorizontalAlignment="Stretch" TextWrapping="Wrap" Text="{Binding datetime}" ></TextBlock>
</DataTemplate>
</GridViewColumn.CellTemplate>
</GridViewColumn>
<GridViewColumn Header="oAmount" Width="120" >
<GridViewColumn.CellTemplate>
<DataTemplate>
<TextBlock HorizontalAlignment="Stretch" TextWrapping="Wrap" Text="{Binding oAmount}"></TextBlock>
</DataTemplate>
</GridViewColumn.CellTemplate>
</GridViewColumn>
<GridViewColumn Header="Term" Width="120" >
<GridViewColumn.CellTemplate>
<DataTemplate>
<TextBlock HorizontalAlignment="Stretch" TextWrapping="Wrap" Text="{Binding Term}"></TextBlock>
</DataTemplate>
</GridViewColumn.CellTemplate>
</GridViewColumn>
<GridViewColumn Header="Action" Width="120" >
<GridViewColumn.CellTemplate>
<DataTemplate>
<TextBlock HorizontalAlignment="Stretch" TextWrapping="Wrap" Text="{Binding Action}"></TextBlock>
</DataTemplate>
</GridViewColumn.CellTemplate>
</GridViewColumn>
<GridViewColumn Header="AffIntRate" Width="120" >
<GridViewColumn.CellTemplate>
<DataTemplate>
<TextBlock HorizontalAlignment="Stretch" TextWrapping="Wrap" Text="{Binding AffIntRate}"></TextBlock>
</DataTemplate>
</GridViewColumn.CellTemplate>
</GridViewColumn>
<GridViewColumn Header="RpmtIntRate" Width="120" >
<GridViewColumn.CellTemplate>
<DataTemplate>
<TextBlock HorizontalAlignment="Stretch" TextWrapping="Wrap" Text="{Binding RpmtIntRate}"></TextBlock>
</DataTemplate>
</GridViewColumn.CellTemplate>
</GridViewColumn>
<GridViewColumn Header="oStatusId" Width="120" >
<GridViewColumn.CellTemplate>
<DataTemplate>
<TextBlock HorizontalAlignment="Stretch" TextWrapping="Wrap" Text="{Binding oStatusId}"></TextBlock>
</DataTemplate>
</GridViewColumn.CellTemplate>
</GridViewColumn>
</GridView>
</ListView.View>
</ListView>
</Grid>
</TabItem>
<ScrollBar x:Name="scrollBar1" Height="13" Width="358"/>
</TabControl>
<!--</StackPanel>-->
<!--users and Logs tabs-->
<StackPanel Name="stkpDetails" Grid.RowSpan="4" Height="400" VerticalAlignment="Top" Grid.Row="1" Grid.Column="1" Width="400" Visibility="Visible" HorizontalAlignment="Center">
<Grid>
<Grid.ColumnDefinitions>
<ColumnDefinition Width="40*"/>
<ColumnDefinition Width="60*"/>
</Grid.ColumnDefinitions>
<Grid.RowDefinitions>
<RowDefinition Height="10*"/>
<RowDefinition Height="*"/>
<RowDefinition Height="*"/>
<RowDefinition Height="*"/>
<RowDefinition Height="*"/>
<RowDefinition Height="*"/>
<RowDefinition Height="*"/>
<RowDefinition Height="*"/>
<RowDefinition Height="*"/>
<RowDefinition Height="*"/>
<RowDefinition Height="*"/>
</Grid.RowDefinitions>
<!---No need to add names as they will not have any interaction-->
<Label Grid.Row="0" Grid.Column="0" Content="UserId" />
<Label Grid.Row="1" Grid.Column="0" Content="QuoteId" />
<Label Grid.Row="2" Grid.Column="0" Content="oAmount" />
<Label Grid.Row="3" Grid.Column="0" Content="oTerm" />
<Label Grid.Row="4" Grid.Column="0" Content="oIntRate" />
<Label Grid.Row="5" Grid.Column="0" Content="p Name" />
<Label Grid.Row="8" Grid.Column="0" Content="o Status" />
<TextBox Grid.Row="0" Grid.Column="1" Name="tbxUserId" />
<TextBox Grid.Row="1" Grid.Column="1" Name="tbxQuoteId" />
<TextBox Grid.Row="2" Grid.Column="1" Name="tbxoAmount" />
<TextBox Grid.Row="3" Grid.Column="1" Name="tbxoTerm" />
<TextBox Grid.Row="4" Grid.Column="1" Name="tbxoIntRate" />
<TextBox Grid.Row="5" Grid.Column="1" Name="tbxpName" />
<ComboBox Name="cbooStatus" Grid.Column="1" Grid.Row="8">
<ComboBoxItem Content="Please select"/>
<ComboBoxItem Content="Approved"/>
<ComboBoxItem Content="Rejected" />
<ComboBoxItem Content="Pending" />
<ComboBoxItem Content="Revised o" />
</ComboBox>
<Button Name="btnUpdate" Grid.Row="9" Grid.Column="2" Content="Update" Width="60" Height="30" HorizontalAlignment="Center" Click="btnUpdate_Click"></Button>
</Grid>
</StackPanel>
</Grid>