How can I set the width of a DataGridColumn to fit

Question

I have a WPF DataGrid that contains some data. I would like to set the width of the columns such that the content fits in and never gets cropped (instead, a horizontal scroll bar should become visible). Additionally, I want the DataGrid to fill the whole place available (I am working with a DockPanel). I am using the following code (simplified):

<DataGrid ItemsSource="{Binding Table}">
    <DataGrid.Columns>
        <DataGridTextColumn MinWidth="100" Width="Auto" Header="Column 1" Binding="{Binding Property1}" />
        <DataGridTextColumn MinWidth="200" Width="Auto" Header="Column 2" Binding="{Binding Property2}" />
    </DataGrid.Columns>
</DataGrid>

This apparently does not work out of the box with Width="Auto" as it always looks something like this:

This obviously looks ugly. I would like to have the whole row selected, or, which would be much better, the columns to fill the whole width, but as one can see, this does not work.

If I use Width="*" instead, the content of the columns gets cropped which is even worse for me.

I found a similar question here, and a workaround was posted there. This may work, but I am working with the MVVM pattern, so the ItemsSource gets updated in the ViewModel and I cannot think about a way of doing it from there, because I cannot access the ActualWidth property of the DataGridColumn. Also, I would like to do it only in XAML if possible.

I would appreciate any help. Thanks!

Edit: As I still don't have a clue what to do about it, I start a small bounty. I would be very happy about a suggestion what one could do about my problem. Thanks again!

Edit 2: After saus' answer I thought about the options again. The problem is that I need to update the Width and the MinWidth properties also during the application is running, so not only after loading the window. I already tried to do something like

column.Width = new DataGridLength(1, DataGridLengthUnitType.Auto);
column.MinWidth = column.ActualWidth;
column.Width = new DataGridLength(1, DataGridLengthUnitType.Star);

in some event that is fired when the underlying ItemsSource of the DataGrid is updating. However, this does not work, as the ActualWidth property does not seem to change after setting the Width on Auto. Is there an option to somehow "repaint" it in order to get the ActualWidth property updated? Thanks!

Answer 1

use this for any column you want to fit to its content: Width = "SizeToCells"