I am new into WPF and i am developing a app with different images, textbox, etc. The problem is here on my screen it all looks ok according to the size of the window with the properties ive set on the window loaded:
private void Window_Loaded(object sender, RoutedEventArgs e)
{
Width = System.Windows.SystemParameters.PrimaryScreenWidth;
Height = System.Windows.SystemParameters.PrimaryScreenHeight;
}
When using the application on my screen it looks like this:

But when using it on a tablet i cant see the Calendar neither the text that says "Fecha nacimiento". Here is the WPF code i am using:
<Window x:Class="BiometricoRegistro.MainWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
Title="RegistrarCliente" Height="978" Width="1600" Loaded="Window_Loaded" WindowState="Maximized">
<Grid>
<Grid.Background>
<ImageBrush ImageSource="Imagenes\home_bg.jpg"/>
</Grid.Background>
<TextBox x:Name="txtbRut" HorizontalAlignment="Left" Height="51" TextWrapping="Wrap" BorderBrush="Transparent" VerticalAlignment="Top" Width="379" Margin="30,230,0,0" FontSize="35" FontWeight="Bold" PreviewTextInput="txtbRut_PreviewTextInput">
<TextBox.Background>
<ImageBrush ImageSource="Imagenes\input.png"/>
</TextBox.Background>
</TextBox>
<TextBox x:Name="txtbRutVer" HorizontalAlignment="Left" Height="51" TextWrapping="Wrap" BorderBrush="Transparent" VerticalAlignment="Top" Width="74" Margin="430,230,0,0" FontSize="35" FontWeight="Bold" TextAlignment="Center">
<TextBox.Background>
<ImageBrush ImageSource="Imagenes\input.png"/>
</TextBox.Background>
</TextBox>
<TextBox x:Name="txtbNombre" HorizontalAlignment="Left" Height="51" TextWrapping="Wrap" BorderBrush="Transparent" VerticalAlignment="Top" Width="474" Margin="30,330,0,0" FontSize="35" FontWeight="Bold">
<TextBox.Background>
<ImageBrush ImageSource="Imagenes\input.png"/>
</TextBox.Background>
</TextBox>
<TextBox x:Name="txtbApellido" HorizontalAlignment="Left" Height="51" TextWrapping="Wrap" BorderBrush="Transparent" VerticalAlignment="Top" Width="474" Margin="30,430,0,0" FontSize="35" FontWeight="Bold">
<TextBox.Background>
<ImageBrush ImageSource="Imagenes\input.png"/>
</TextBox.Background>
</TextBox>
<TextBox x:Name="txtbEmail" HorizontalAlignment="Left" Height="51" TextWrapping="Wrap" BorderBrush="Transparent" VerticalAlignment="Top" Width="474" Margin="30,530,0,0" FontSize="35" FontWeight="Bold">
<TextBox.Background>
<ImageBrush ImageSource="Imagenes\input.png"/>
</TextBox.Background>
</TextBox>
<Calendar x:Name="calendar" HorizontalAlignment="Left" Height="170" VerticalAlignment="Top" Width="260" Margin="0,720,0,57"/>
<Button x:Name="btnRegistrar" Content="Registrar" HorizontalAlignment="Center" Height="118" VerticalAlignment="Center" Width="296" Margin="775,0,221,100" Click="btnRegistrar_Click"/>
<ComboBox x:Name="cbPorcentaje" HorizontalAlignment="Left" Height="40" Margin="30,630,0,0" VerticalAlignment="Top" Width="230" HorizontalContentAlignment="Center" FontSize="35">
<ComboBoxItem Content="A" FontSize="35"></ComboBoxItem>
<ComboBoxItem Content="B" FontSize="35"></ComboBoxItem>
<ComboBoxItem Content="C" FontSize="35"></ComboBoxItem>
</ComboBox>
<TextBlock HorizontalAlignment="Left" Height="37" Margin="30,176,0,0" TextWrapping="Wrap" Text="Rut cliente" VerticalAlignment="Top" Width="474" FontFamily="/BiometricoRegistro;component/Fonts/#Alex Brush" FontSize="36" Foreground="White"/>
<TextBlock HorizontalAlignment="Left" Height="37" Margin="30,286,0,0" TextWrapping="Wrap" Text="Nombres cliente" VerticalAlignment="Top" Width="474" FontFamily="/BiometricoRegistro;component/Fonts/#Alex Brush" FontSize="36" Foreground="White"/>
<TextBlock HorizontalAlignment="Left" Height="37" Margin="30,386,0,0" TextWrapping="Wrap" Text="Apellidos cliente" VerticalAlignment="Top" Width="474" FontFamily="/BiometricoRegistro;component/Fonts/#Alex Brush" FontSize="36" Foreground="White"/>
<TextBlock HorizontalAlignment="Left" Height="37" Margin="30,486,0,0" TextWrapping="Wrap" Text="Email cliente" VerticalAlignment="Top" Width="474" FontFamily="/BiometricoRegistro;component/Fonts/#Alex Brush" FontSize="36" Foreground="White"/>
<TextBlock HorizontalAlignment="Left" Height="37" Margin="30,586,0,0" TextWrapping="Wrap" Text="Tipo Descuento" VerticalAlignment="Top" Width="474" FontFamily="/BiometricoRegistro;component/Fonts/#Alex Brush" FontSize="36" Foreground="White"/>
<TextBlock HorizontalAlignment="Left" Height="37" Margin="30,678,0,230" TextWrapping="Wrap" Text="Fecha nacimiento" VerticalAlignment="Top" Width="474" FontFamily="/BiometricoRegistro;component/Fonts/#Alex Brush" FontSize="36" Foreground="White"/>
<TextBlock x:Name="txtResult" HorizontalAlignment="Left" Height="64" Margin="501,0,0,57" TextWrapping="Wrap" Text="" VerticalAlignment="Bottom" Width="823" FontSize="46" Foreground="Red" FontFamily="PMingLiU-ExtB"/>
</Grid>
</Window>
RowDefinitions andColumnDefinitions?Grid's cell so you should useRowDefinitionsandColumnDefinitionas har07 said.