BallanceTasEditor/BallanceTASEditor/UI/AddItem.xaml

<Window x:Class="BallanceTASEditor.UI.AddItem"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
        xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
        xmlns:local="clr-namespace:BallanceTASEditor.UI"
        xmlns:converter="clr-namespace:BallanceTASEditor.UI"
        mc:Ignorable="d"
        Title="Add Item" Height="200" Width="400" WindowStyle="ToolWindow" WindowStartupLocation="CenterOwner">
    <Window.Resources>
        <converter:AddItemConverter x:Key="conv_addItem"/>
        <converter:FPS2DeltaTimeConverter x:Key="conv_fps2DeltaTime"/>
    </Window.Resources>
    
    <Grid>
        <Grid.RowDefinitions>
            <RowDefinition Height="auto"/>
            <RowDefinition Height="auto"/>
            <RowDefinition Height="auto"/>
            <RowDefinition Height="*"/>
            <RowDefinition Height="auto"/>
        </Grid.RowDefinitions>
        <Grid.ColumnDefinitions>
            <ColumnDefinition Width="auto"/>
            <ColumnDefinition Width="*"/>
        </Grid.ColumnDefinitions>

        <TextBlock Margin="5" Grid.Column="0" Grid.Row="0" Text="Count" VerticalAlignment="Center"/>
        <TextBlock Margin="5" Grid.Column="0" Grid.Row="1" Text="FPS" VerticalAlignment="Center"/>
        <TextBlock Margin="5" Grid.Column="0" Grid.Row="2" Text="Delta Time" VerticalAlignment="Center"/>

        <TextBox x:Name="uiTextbox_Count" Margin="5" Padding="5" Grid.Row="0" Grid.Column="1" VerticalAlignment="Center"/>
        <TextBox x:Name="uiTextbox_FPS" Margin="5" Padding="5" Grid.Row="1" Grid.Column="1" VerticalAlignment="Center"/>
        <TextBlock x:Name="uiText_DeltaTime" Margin="5" Padding="5" Grid.Row="2" Grid.Column="1" VerticalAlignment="Center"
                   Text="{Binding Converter={StaticResource conv_fps2DeltaTime}, Mode=OneWay, ElementName=uiTextbox_FPS, Path=Text}"/>

        <StackPanel Orientation="Horizontal" Margin="5" HorizontalAlignment="Right" Grid.ColumnSpan="2" Grid.Row="4">
            <Button x:Name="uiBtn_OK" Margin="5" Padding="5" Content="OK" MinWidth="50" Click="funcBtn_OK">
                <Button.IsEnabled>
                    <MultiBinding Converter="{StaticResource conv_addItem}" Mode="OneWay">
                        <Binding ElementName="uiTextbox_Count" Path="Text"/>
                        <Binding ElementName="uiTextbox_FPS" Path="Text"/>
                    </MultiBinding>
                </Button.IsEnabled>
            </Button>
            <Button x:Name="uiBtn_Cancel" Margin="5" Padding="5" Content="Cancel" MinWidth="50" Click="funcBtn_Cancel"/>
        </StackPanel>
    </Grid>
</Window>