MainWindow.xaml

<Window x:Class="Wpf_Proj1.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
        mc:Ignorable="d"
        Title="Names" Height="180" Width="260">
    <Grid Margin=" 10">
        <Grid.RowDefinitions>
            <RowDefinition Height="Auto" />
            <RowDefinition Height="*" />
        </Grid.RowDefinitions>
        <Grid.ColumnDefinitions>
            <ColumnDefinition Width="*" />
            <ColumnDefinition Width="*" />
        </Grid.ColumnDefinitions>

        <Label Grid.Column="1">Names</Label>
        <ListBox Grid.Row="1" Grid.Column="0" x:Name ="lstNames" />

        <StackPanel Grid.Column="1" Grid.Row="1" Margin="5,0,0,0">
            <TextBox x:Name="txtName" />
            <Button x:Name="btnAdd" Margin="0,5,0,0" Content="Add Name" Click="btnAdd_Click" />
        </StackPanel>
    </Grid>
</Window>