kmpdfkit_demo/Demo/Examples/Compdfkit_Tools/DigitalSignature/AddCertificationControl/AddExistedCertificationControl.xaml

<UserControl x:Class="Compdfkit_Tools.PDFControl.AddExistedCertificationControl"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
        xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
        xmlns:local="clr-namespace:Compdfkit_Tools.PDFControl"
        xmlns:common="clr-namespace:Compdfkit_Tools.Common"
        mc:Ignorable="d"
        Height="277" Width="470">
    <UserControl.Resources>
        <common:TextLengthToVisibilityConverter x:Key="TextLengthToVisibilityConverter"></common:TextLengthToVisibilityConverter>
    </UserControl.Resources>
    <Grid>
        <Grid.RowDefinitions>
            <RowDefinition Height="auto"></RowDefinition>
            <RowDefinition Height="auto"></RowDefinition>
            <RowDefinition Height="auto"></RowDefinition>
            <RowDefinition></RowDefinition>
        </Grid.RowDefinitions>
        <TextBlock TextWrapping="Wrap" FontSize="14" Foreground="#000000" Margin="10,20,10,20" Height="40"
                   Text="Browse digital ID files. Digital ID files are password protected. If you do not know its password, you cannot access the digital ID card.">
        </TextBlock>
        <StackPanel Grid.Row="1" Orientation="Horizontal" Margin="10,0,0,8">
            <TextBlock Text="Files" Foreground="#43474D" FontSize="14" VerticalAlignment="Center" Margin="10,0,10,0" HorizontalAlignment="Left" Width="58" FontFamily="Segoe UI"></TextBlock>
            <Grid IsEnabled="{Binding InputEnable}">
                <TextBox Width="258" Height="28"  x:Name="FileNameTxt" VerticalContentAlignment="Center" VerticalAlignment="Center" IsReadOnly="True"/>
                <TextBlock Text="Select a file" Margin="8" VerticalAlignment="Center"   Visibility="{Binding ElementName=FileNameTxt, Path=Text, Converter={StaticResource TextLengthToVisibilityConverter}}" IsHitTestVisible="False"  Foreground="#BBB"></TextBlock>
            </Grid>
            <Button x:Name="SelectFileBtn" Content="Select File" Width="90" Height="28" FontSize="14" FontFamily="Segoe UI" Margin="8,0,0,0" Click="SelectFileBtn_Click"></Button>
        </StackPanel>
        <StackPanel Grid.Row="2" Orientation="Horizontal"  Margin="10,0,0,8">
            <TextBlock Foreground="#43474D" Width="58" FontSize="14" FontFamily="Segoe UI" Text="Password" VerticalAlignment="Top" Margin="10,5,10,0"></TextBlock>
            <StackPanel  Margin="0,0,0,0">
                <PasswordBox Name="PasswordBoxTxt" Padding="5,0,0,0" Width="258" Height="28"  VerticalContentAlignment="Center" VerticalAlignment="Center"></PasswordBox>
                <TextBlock Name="ErrorTipsText" Foreground="Red" Margin="0,4,0,0"></TextBlock>
            </StackPanel>
        </StackPanel>
        <Grid Grid.Row="4">
            <StackPanel  Orientation="Horizontal" HorizontalAlignment="Right" VerticalAlignment="Bottom" Margin="24"> 
                <Button x:Name="CancelBtn" Content="Cancel"  Margin="0,0,10,0" Width="112" Height="32" BorderThickness="1" Click="CancelBtn_Click"></Button>
                <Button x:Name="DoneBtn" Content="Done" Width="112" Height="32" BorderThickness="1" Click="DoneBtn_Click"></Button>
            </StackPanel>
        </Grid> 
    </Grid>
</UserControl>