How to size the WPF Grid panel this way?

Question

I have this pretty simple window with a Grid containing two columns, a TextBlock and a TextBox.

What I need it to set the column 0 to automatically size to its content and to have column 1 (content) to be 4 times the size of the column 0.

How can I do that. I will create a Grid descendant if this is the solution because I really need this feature.

Edit: more explanations. The content of the column 0 won't change at runtime so the size of the column 0 or column 1 must not change on runtime. The grid will be the child of a window configured with SizeToContent="WidthAndHeight" so no extra space must exist.

Answer to Dmitry: I tried what you say with the following code and it is not working at all:

<Window x:Class="UnderstandSizing.Window1"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
Title="Window1" 
SizeToContent="WidthAndHeight" >
<Grid>
    <Grid.ColumnDefinitions>
        <ColumnDefinition Width=".25*" />
        <ColumnDefinition Width=".75*" />
    </Grid.ColumnDefinitions>
    <Grid.RowDefinitions>
        <RowDefinition Height="Auto" />
    </Grid.RowDefinitions>
    <TextBlock Grid.Column="0" Text="THIS IS THE LABEL:" />
    <TextBox Grid.Column="1" Text="content" />
</Grid>
</Window>

Last Edit: Why the hell do I (or anyone) need this?

One of the nice things of WPF is its hability to work without fixed sizes right? If you are impaired and you have a bigger font size everything will look fine. If you translate your UI to another language that needs x2 size everything will look fine. If you have different PPI settings everything will look fine.

But what I don't want to see is screens changing its size at runtime because users are not used to this. That's why I want to set the size of the entry fields to a multiple of a know field. If I let the label cell to re size to what it needs and then I set the content cell to a multiplier of the label I will get the benefits of autosizing with the behaviour that users expect of having fixed size screens (unless they change it resizing it).

Answer 1

You can use bindings on grid columns:

<Grid.ColumnDefinitions>
   <ColmunDefinition Width="Auto" x:Name="firstCol"/>
   <ColumnDefinition Width="{Binding ActualWidth, ElementName=firstCol, Converter={StaticResource MultiplyConverter}, ConverterParameter=4}" />
</Grid.ColumnDefinitions>

Then the converter:

public class MultiplyConverter : IValueConverter
{
    public object Convert(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture)
    {
        double originalValue;
        double multiplier;
        if (value != null && parameter != null && 
            double.TryParse(value.ToString(), out originalValue) &&
            double.TryParse(parameter.ToString(), out multiplier)) //Can be lots of things: sentinel object, NaN (not a number)...
        {
            return originalValue * multiplier;
        }
        else return Binding.DoNothing;
    }

    public object ConvertBack(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture)
    {
        throw new NotImplementedException();
    }
}

You could write an attached property for grid columns also.