Populating ComboBox inside ListView in WPF
I have populated a ComboBox
inside a ListView
. Screen shot is given below
As shown above it's displaying "M", "a", "c" instead of "Mac". Why it is separating the word into characters?
In code behind file I've written
ItemCategoryDAL itemCategoryDalObj = new ItemCategoryDAL(); DataTable dataTable = itemCategoryDalObj.GetAllItemCategory(); listView1.ItemsSource = dataTable.DefaultView;
And in .xaml file I've written:
<ListView Height="148" HorizontalAlignment="Left" Margin="23,12,0,0" Name="listView1" VerticalAlignment="Top" Width="447" > <ListView.View> <GridView> - - - - - - - - - - - - - - - - <GridViewColumn Header="Category Name" Width="150"> <GridViewColumn.CellTemplate> 开发者_如何学C <DataTemplate> <ComboBox ItemsSource="{Binding Path=IC_NAME }" Width="120" /> </DataTemplate> </GridViewColumn.CellTemplate> </GridViewColumn> - - - - - - - - - - - - - - - - - - </GridView> </ListView.View> </ListView>
I'm using Visual Studio 2010
Screen shot of dataTable
which I used as ItemSource
for the ListView.(Taken during debuging)
A ComboBox
allows the user to select from multiple items. It populates itself by iterating through all of the items in its ItemsSource
and adding each item to its Items
.
You're setting ItemsSource
to a property that returns a string. Since a string can be iterated over, the ComboBox
is populating itself with the items it gets when iterating over it, so the string "Mac" turns into the items "M", "a", and "c".
That's why you're seeing what you're seeing. The question really is: what did you expect to see (or what do you want to see) and why? What items should the ComboBox
be displaying? If you want it to display all of the category names that appear in the DataTable
, you could do something like:
ItemsSource="{Binding RelativeSource={RelativeSource AncestorType=ListView}, Path=ItemsSource}"
and then pull out the IC_Name
column from each item using a DataTemplate
:
<ComboBox.ItemTemplate>
<DataTemplate>
<TextBlock Text="{Binding IC_Name}"/>
</DataTemplate>
</ComboBox.ItemTemplate>
Note that there are going to be all kinds of unexpected phenomena that you encounter by doing this. For instance, if only one row in the table has "Foo" as a value of IC_Name
, the moment the user selects some other value for that row and the table gets updated, the value "Foo" will disappear from all of the ComboBox
es, making it impossible for the user to undo that change. Also, if five rows contain "Foo", each ComboBox
will display all five instances of "Foo" in their dropdown.
The binding seems to work, IC_NAME exists and returns "Mac" as a string. This will implicitely converted to an enumerable of string with three entries: "M", "a" and "c". And this is then the ItemsSource of your ComboBox.
<ComboBox ItemsSource="{Binding Path=IC_NAME }" Width="120" />
Probably it should be something like:
<ComboBox
SelectedItem="{Binding Path=IC_NAME}"
ItemsSource="{Binding Path=NameOfACollectionProperty }"
Width="120" />
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