WPF主从输入 [英] WPF master-detail input

问题描述

我有一个主从用户界面. (可选)用户应该能够使用默认值填充某些字段.
所以我说

I have a master-detail user interface. Optionally, the user should be able to populate some of the fields with default values.
So I say

void button1_Click(object sender, RoutedEventArgs e)
       {
       textBox1.Text = "6545" // this is fine
           listView1.Items.Add(new { name = "test" , value = "fifty" }); // this throws an exception
       }

例外是:

使用ItemsSource时操作无效.改为使用ItemsControl.ItemsSource访问和修改元素.


??????为什么我不能通过GUI模拟数据输入的代码?

===========

后面的代码的相关部分是:

Exception is:

Operation is not valid while ItemsSource is in use. Access and modify elements with ItemsControl.ItemsSource instead.


????? Why can''t I mimic in code the input of data via the GUI?

============

Relevant portions of the code-behind are:

private void Window_Loaded(object sender, RoutedEventArgs e) {

        this.PostData = db.Posts;

        MasterViewSource = (CollectionViewSource)this.FindResource("MasterView");
            DetailViewSource = (CollectionViewSource)this.FindResource("DetailView");
        MasterView = (BindingListCollectionView)this.MasterViewSource.View;
            MasterView.CurrentChanged += new EventHandler(MasterView_CurrentChanged);
            DetailView = (BindingListCollectionView)this.DetailViewSource.View;
        //.................///

    }

----------

----------

My xaml has


<CollectionViewSource x:Key="MasterView" />
  <CollectionViewSource Source="{Binding Source={StaticResource MasterView}, Path=''PostDetails''}" x:Key="DetailView" />

  <!--  .................... -->

 <ListView Name="listView1" IsSynchronizedWithCurrentItem="True" ItemsSource="{Binding Source={StaticResource DetailView}}">
     <!--  ............. -->
    <ListView.View>
        <GridView>
            <!--  .............. -->
            <GridViewColumn>
                            <GridViewColumn.CellTemplate>
                                    <DataTemplate>
                                            <ComboBox ItemsSource="{Binding Source={StaticResource NameLookup}}"SelectedValue="{Binding Path=AccountName}" DisplayMemberPath="name"                                         SelectedValuePath="name" />
                                         </DataTemplate>
                </GridViewColumn.CellTemplate>
                        </GridViewColumn>
                 </GridView>
         </ListView.View>
 </ListView>

-------


谢谢

-------


Thanks

推荐答案

您无法执行此操作，因为您实际上是在使用数据绑定，而不是从头开始直接分配值.您在这里有两个选择，或者将项目添加到您绑定到的集合中(应该实现INotifyCollectionChanged-ObservableCollection在这里是一个不错的选择)，或者您需要使用以下内容的变体:

You can''t do this because you are actually using a data binding, rather than directly assigning values from the start. You have two choices here, either add the items to the collection you have bound to (which should implement INotifyCollectionChanged - ObservableCollection is a good choice here), or you need to use a variation of the following:

ICollectionView view = (ICollectionView)CollectionViewSource.GetDefaultView(listView1.ItemsSource);
var item = view.CurrentItem;
item.Add(....);

您去了，应该会有所帮助.

There you go, that should help.

这篇关于WPF主从输入的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！