ListBox 绑定多个元素问题

[dwtyxugy1]

<ListBox x:Name="PostList" Grid.Column="0" Grid.Row="2"
Margin="40 10 10 10"
HorizontalContentAlignment="Left" VerticalContentAlignment="Bottom" DisplayMemberPath="Posts"
>
<ListBox.ItemTemplate>
<DataTemplate>
<StackPanel>
<TextBlock Text="{Binding numBer}" Margin="5" x:Name="gss" Foreground="Aquamarine"></TextBlock>
<TextBlock Text="{Binding Title}" Margin="5" x:Name="gtt" Foreground="Aquamarine"></TextBlock>
</StackPanel>
</DataTemplate>
</ListBox.ItemTemplate>
</ListBox>

public class Blog
{
private string _numBer;
private string _Title;
public Blog(string n ,string t)
{
numBer = n;
Title = t;
}
public String numBer
{
get { return _numBer; }
set { _numBer = value; }
}

public String Title
{
get { return _Title; }
set { _Title = value; }
}
}


public class Datas : ObservableCollection<Blog>
{
}

Datas da = new Datas();
da.Add(new Blog("稻香", "周杰伦"));
da.Add(new Blog("夜曲", "周杰伦"));
da.Add(new Blog("日不落", "蔡依林"));
da.Add(new Blog("说爱你", "蔡依林"));
//设置数据源对象
this.PostList.ItemsSource = da;
为何没显示？请高手指定

[zhuzhi]

在this.PostList.ItemsSource = da;
前面再加一个PostList.DataContext = da;看看

[dwtyxugy1]

也不行

[dwtyxugy1]

知道原因了