Getting Started
EO.Pdf
EO.Web
EO.WebBrowser
EO.Wpf
- Overview
- Installation & Deployement
- Skin & Theme
- Common Taskes and Services
- EO.Wpf Buttons
- EO.Wpf Calendar & DatePicker
- EO.Wpf ComboBox
- EO.Wpf DockView
- EO.Wpf Gauge
- EO.Wpf ListBox
- EO.Wpf Menu
- EO.Wpf MaskedEdit
- EO.Wpf ProgressBar
- EO.Wpf Slider
- EO.Wpf SpinEdit
- EO.Wpf SplitView
- EO.Wpf TabControl
- EO.Wpf TreeView
  - EO.Wpf TreeView
  - Static TreeView
  - Dynamic TreeView from Data Source
  - Drag & Drop
  - Checkboxes
  - Node Editing
  - TreeViewItem Icon
- EO.Wpf Utility Controls
- EO.Wpf WindowChrome
- Sample Data Objects
Common Topics
Reference

Table of Contents

Checkboxes

EO.Wpf TreeView offers built-in checkboxes support. This section covers the following topics:

Enabling Checkboxes

Auto Check/Uncheck Parent/Child Item

Handling CheckStateChanged event

Enabling Checkboxes

You can display a checkbox on a single TreeViewItem by setting that TreeViewItem's ShowCheckBox to true:

XAML

Copy

<Window x:Class="Test.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:eo="http://schemas.essentialobjects.com/wpf/"
        Title="MainWindow" Height="250" Width="350">
    <StackPanel>
        <eo:TreeView x:Name="TreeView1" Width="200" Height="200" HorizontalAlignment="Left">
            <eo:TreeViewItem Header="Parent Item 1">
                <eo:TreeViewItem Header="Child Item 1" ShowCheckBox="True"></eo:TreeViewItem>
                <eo:TreeViewItem Header="Child Item 2"></eo:TreeViewItem>
            </eo:TreeViewItem>
            <eo:TreeViewItem Header="Parent Item 2"></eo:TreeViewItem>
        </eo:TreeView>
    </StackPanel>
</Window>

The above code produces the following result:

Property ShowCheckBox is inheritable, so if it is set it on a parent node, all children node will display a checkbox:

XAML

Copy

<Window x:Class="Test.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:eo="http://schemas.essentialobjects.com/wpf/"
        Title="MainWindow" Height="250" Width="350">
    <StackPanel>
        <eo:TreeView x:Name="TreeView1" Width="200" Height="200" HorizontalAlignment="Left">
            <eo:TreeViewItem Header="Parent Item 1" ShowCheckBox="True">
                <eo:TreeViewItem Header="Child Item 1"></eo:TreeViewItem>
                <eo:TreeViewItem Header="Child Item 2"></eo:TreeViewItem>
            </eo:TreeViewItem>
            <eo:TreeViewItem Header="Parent Item 2"></eo:TreeViewItem>
        </eo:TreeView>
    </StackPanel>
</Window>

The above code produces the following result:

It can also be set on the TreeView:

XAML

Copy

<Window x:Class="Test.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:eo="http://schemas.essentialobjects.com/wpf/"
        Title="MainWindow" Height="250" Width="350">
    <StackPanel>
        <eo:TreeView x:Name="TreeView1" Width="200" Height="200" HorizontalAlignment="Left" ShowCheckBox="True">
            <eo:TreeViewItem Header="Parent Item 1">
                <eo:TreeViewItem Header="Child Item 1"></eo:TreeViewItem>
                <eo:TreeViewItem Header="Child Item 2"></eo:TreeViewItem>
            </eo:TreeViewItem>
            <eo:TreeViewItem Header="Parent Item 2"></eo:TreeViewItem>
        </eo:TreeView>
    </StackPanel>
</Window>

The above code produces the following result:

Once checkbox is enabled, you can use CheckState to get or set an item's check state.

Auto Check/Uncheck Parent/Child Item

EO.Wpf TreeView can automatically check/uncheck the parent item or all child items when a item is checked/unchecked. To automatically check a parent item, set the TreeView's AutoCheckParent property to true:

XAML

Copy

<Window x:Class="Test.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:eo="http://schemas.essentialobjects.com/wpf/"
        Title="MainWindow" Height="250" Width="350">
    <StackPanel>
        <eo:TreeView x:Name="TreeView1" Width="200" Height="200" 
            HorizontalAlignment="Left" ShowCheckBox="True" AutoCheckParent="True">
            <eo:TreeViewItem Header="Parent Item 1">
                <eo:TreeViewItem Header="Child Item 1"></eo:TreeViewItem>
                <eo:TreeViewItem Header="Child Item 2"></eo:TreeViewItem>
            </eo:TreeViewItem>
            <eo:TreeViewItem Header="Parent Item 2"></eo:TreeViewItem>
        </eo:TreeView>
    </StackPanel>
</Window>

When AutoCheckParent is set to true, the parent item's checkbox status will be automatically updated when a child item is checked or unchecked. The following image demonstrated that when "Child Item 1" is checked, "Parent Item 1" is in indeterminate state (it will be in "checked" state if all of its children items are checked).

You can also set AutoCheckChildren to true. When AutoCheckChildren is set to true, checking/unchecking a parent item automatically check/uncheck all its children items.

Handling CheckStateChanged event

TreeViewItem exposes CheckStateChanged event which is fired when the TreeViewItem's CheckState is changed. Because CheckStateChanged is a routed event, you can handle it on the TreeView:

XAML

Visual Basic.NET

Copy

<eo:TreeView Width="200" Height="200" HorizontalAlignment="Left" 
    ShowCheckBox="True" eo:TreeViewItem.CheckStateChanged="TreeView_CheckStateChanged">
    <eo:TreeViewItem Header="Parent Item 1">
        <eo:TreeViewItem Header="Child Item 1"></eo:TreeViewItem>
        <eo:TreeViewItem Header="Child Item 2"></eo:TreeViewItem>
    </eo:TreeViewItem>
    <eo:TreeViewItem Header="Parent Item 2">
        <eo:TreeViewItem Header="Child Item 3"></eo:TreeViewItem>
        <eo:TreeViewItem Header="Child Item 4"></eo:TreeViewItem>
        <eo:TreeViewItem Header="Child Item 5"></eo:TreeViewItem>
    </eo:TreeViewItem>
</eo:TreeView>

private void TreeView_CheckStateChanged(object sender, RoutedEventArgs e)
{
    EO.Wpf.TreeViewItem item = (EO.Wpf.TreeViewItem)e.Source;

    MessageBox.Show("Item = " + item.Header.ToString() + ", New Check State = " + item.CheckState.ToString());
}

Private Sub TreeView_CheckStateChanged(sender As Object, e As RoutedEventArgs)
    Dim item As EO.Wpf.TreeViewItem = DirectCast(e.Source, EO.Wpf.TreeViewItem)

    MessageBox.Show("Item = " & item.Header.ToString() & ", New Check State = " & item.CheckState.ToString())
End Sub

In the above code, even though the event is raised on the TreeViewItem objects, it is handled on the TreeView. Inside the handler you can cast the event argument's Source property to a TreeViewItem object.