Columns with Star width are set to the minimum available width

[berruezo]

When setting a GridLength of GridUnitType.Star in a TemplateColumn, the actual width is not calculated correctly, and the column gets the minimum width possible:

Digging into the code I saw that this method is always receiving 0 as the availableWidth, whereas in the previous version it received the actual available width for the column

[grokys]

I've tried to repro this but been unable to. I know we spoke in chat and you were unable to get a simple repro, but could you maybe describe how your columns are set up? Might give more of a clue.

[berruezo]

Yes, the TemplateColumns in the table are created using this method:

        static IColumn<T> BuildTemplateColumn(
            string columnName,
            int columnWidth,
            Func<string, T, PlasticTableCell> cellFunc,
            IComparer<T> comparer)
        {
            return new TemplateColumn<T>(
                columnName,
                new FuncDataTemplate<T>((T node, INameScope ns) =>
                {
                    return BuildCellControl(columnName, cellFunc, node);
                }, true),
                null,
                GetGridLength(columnWidth),
                new TemplateColumnOptions<T>
                {
                    CompareAscending = Sort(comparer, false),
                    CompareDescending = Sort(comparer, true)
                })
            {
                Tag = columnName,
            };

For the first column, the grid length is new GridLength(1, GridUnitType.Star); And for the other two it's new GridLength(100, GridUnitType.Pixel);

Also, the TreeDataGrid is inside a non-resizable Window; it has a fixed width, and these two options:

            CanResize = false;
            SizeToContent = SizeToContent.Height;

[berruezo]

I saw that when executing a LayoutPass on the TreeDataGrid the Bounds.Size is 0,0.

The EffectiveViewport.Size is correct, but the Intersect operation is causing the Viewport to be of size 0,0 as well, and thus using a wrong availableWidth when calculating the star width.

On the previous version, the Bounds.Size was correct, and the Viewport was not empty when exiting this method. Is this of any help?

[grokys]

Ok, the missing part was that the TreeDataGrid needs to have no items for this to repro. Fix incoming.