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POWPF Treeview in VB.net
 

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    <p>I have been looking for a some working code for the last couple of days to set up a treeview in my WPF app to display some database data. I use VB as i am much more confident in it - which drastically limited the code examples out there. More examples i found used manually entered data to populate each node versus a database which was little help. I finally found some code which bound the each node to a query and related the query via a DataRelation. Great this should work perfect!</p> <p>The example used the Northwind database so I changed it to my database and plugged in the queries. To my shock the treeview populated fine except.... all the data is invisible.</p> <p>Here is the code: </p> <pre><code>Imports MySql.Data.MySqlClient Imports System.Data Imports System.ComponentModel Imports System.Xml Imports System.IO Class Window2 Dim connStr As String = "Server=127.0.0.1;Database=psdb;Uid=root;Pwd=;Connect Timeout=30;" Dim conn As New MySqlConnection(connStr) Function GetRelationalData() As DataSet Dim CategoryAdapter As MySqlDataAdapter = New MySqlDataAdapter("select distinct Dist_name, dist_id from distributors".ToString, conn) Dim ProductsAdapter As MySqlDataAdapter = New MySqlDataAdapter("select d.dist_id, t.Title_name, title_id from titles t, distributors d where d.dist_id = t.dist_id".ToString, conn) Dim ProductData As DataSet = New DataSet() CategoryAdapter.Fill(ProductData, "Categories") 'fill Categories ProductsAdapter.Fill(ProductData, "Products") 'fill products Dim CategoryRelation As DataRelation CategoryRelation = New DataRelation("ChildrenRelationship", _ ProductData.Tables("Categories").Columns("dist_id"), _ ProductData.Tables("Products").Columns("dist_id"), True) CategoryRelation.Nested = True ProductData.Relations.Add(CategoryRelation) Return ProductData End Function Private Sub Button1_Click(ByVal sender As System.Object, _ ByVal e As RoutedEventArgs) Handles Button1.Click BindData() End Sub Private Sub BindData() TreeView1.DataContext = GetRelationalData() End Sub End Class </code></pre> <p>and the XAML:</p> <pre><code>&lt;Window x:Class="Window2" xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" Title="Window1" Height="400" Width="550"&gt;&lt;Window.Resources&gt; &lt;DataTemplate x:Key="ProductTemplate" &gt; &lt;TextBlock Text="{Binding ProductName}"&gt;&lt;/TextBlock&gt; &lt;/DataTemplate&gt; &lt;HierarchicalDataTemplate x:Key="CategoryTemplate" ItemsSource="{Binding ChildrenRelationship}" ItemTemplate="{StaticResource ProductTemplate}"&gt; &lt;TextBlock Text="{Binding CategoryName}"&gt;&lt;/TextBlock&gt; &lt;/HierarchicalDataTemplate&gt; &lt;/Window.Resources&gt; &lt;Grid&gt; </code></pre> <p>and here what i end up with the data seems to be there but you can't see it. Help!</p> <p><img src="https://i.stack.imgur.com/KH3lu.jpg" alt="enter image description here"></p> <p>PS there may be some confusion as to the objects. I went back tried to keep as close to the original code as possible when i discovered the problem only replacing the queries with my own - the original code used "Categories" and "Products" where as I "use Distributors" and "Titles"</p>
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    1. COThis isn't a question. If your question is "How do I make the data visible" then you need to post some code or links or something.
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    2. COyou should post some code, that will really help
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    3. COYour TreeView and associated templates should be defined in XAML. VB/C# shouldn't matter.
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      1. USAaron McIver
 

Querying!

 
Guidance
A row detail

Detail views are divided into sections. All the information in the data section comes from columns in the selected row. The other sections display data from other, related rows.

Related data can be related in a to-one or a to-many fashion. Captions of data related in a to-many fashion link to a list view showing a filtered view of the table.

Try moving around until you find a non-empty to-many entry and click on the label to get to one. You can move back to the root by clicking on the database name in the header.

SQuiL has stopped working due to an internal error.

If you are curious you may find further information in the browser console, which is accessible through the devtools (F12).

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