XAML : Change button text depending on a variable

Hey guys,
A PowerShell XAML question: How can you change a button 's ‘Content’ after it has been pressed?
I’m loading a Window from where I can search for a user and enable or disable that user.
Depending on the initial “status” of the user I’d like to change the text on the button to show the action to perform
e.g.: If the searched user is disabled, the text on the button has to change to ‘enable’ - and vice versa

As I’m very new to building a GUI with XAML, I have no idea how to do this in PowerShell.

Example of the code below.

 

function SearchUser
{
$global:user = Get-ADUser $SearchText.Text
}

function Enable-Disable
{
if (($user.Enabled).ToString() -eq "True")
{
# {Change Content EnableDisableButton to 'Disable'}
# Disable-ADAccount $user
}

if (($user.Enabled).ToString() -eq "False")
{
# {Change Content of EnableDisableButton to 'Enable'}
# Enable-ADAccount $user
}
}

Add-Type -AssemblyName PresentationFramework

[xml]$xaml = @"
<Window Title="Test" xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" x:Name="Window">
<Grid>
<Label HorizontalAlignment="Left" VerticalAlignment="Top" Name="SearchLabel" Content="Search (sAMAccountName):" Width="300" Height="25" Margin="10,10,0,0" />
<TextBox HorizontalAlignment="Left" VerticalAlignment="Top" Name="SearchTextBox" Width="300" Height="30" Margin="10,35,0,0" />
<Button HorizontalAlignment="Left" VerticalAlignment="Top" Name="SearchButton" Content="SEARCH" Width="300" Height="50" Margin="10,75,0,0" />

<Label HorizontalAlignment="Left" VerticalAlignment="Top" Name="EnableDisableLabel" Content="Enable or Disable a User:" Width="300" Height="25" Margin="10,175,0,0" />
<Button HorizontalAlignment="Left" VerticalAlignment="Top" Name="EnableDisableButton" Content="ENABLE OR DISABLE" Width="300" Height="50" Margin="10,200,0,0" />
</Grid>
</Window>
"@

$reader = (New-Object System.Xml.XmlNodeReader $xaml)
$window = [Windows.Markup.XamlReader]::Load($reader)

$global:SearchText = $window.FindName("SearchTextBox")

$Search = $window.FindName("SearchButton")
$Search.Add_Click({SearchUser})

$EnableDisable = $window.FindName("EnableDisableButton")
$EnableDisable.Add_Click({EnableDisable})

$window.ShowDialog()

try without using global variables and functions.

$window = [Windows.Markup.XamlReader]::Load($reader)

$Search= $window.FindName("SearchButton")
$Search.Text = 'Disabled'
if($user.Enabled){
    $Search.Text = 'Disabled'
}
#....