1. Give a specific name to your view on the form.
When you added your List View on the form, you need to set a name, which will help you to find this List View on the form. Otherwise, trying to find a list view by class will select all List Views on your form. I personally prefer selecting controls on the SmartForm by something, I can control in the Designer.
2. Create a view parameter for your Grid Width.
If you want to change the width of the list view grid, depending on where you place it, you can create a parameter for your list view. If you do not need this level of flexibility, you can simply skip this step and in the next one just use the static value for the width.
3. Prepare the script
On the List View you need to run a short script. For this you need to put an empty hidden literal Data Label on the view and create an expression with the script below. The expression must not be connected to the data label. Pay attention to the first selector, which must contain the name of the view from p.1.
4. Create a rule for changing the column width.
When you run the script above, the width of the view will be increased, however, the column headers will keep the initial sizes. This happens because the headers use the width in % and their sizes will be recalculated when you try to change something from the UI, e.g. changing the column width at runtime etc. Nevertheless, I found a tiny workaround. After you changed the width of the view, you need to hide any column and then show it. This will make K2 to recalculate the width of the column headers, taking into account the new width of the view.
5. Call the rule upon the view initialization.
6. Enjoy the result
And this is how the List View with horizontal scrolling looks on mobile devices.