ColumnDefinitions as a StaticResource throws NullReferenceException when assigning to multiple Grids.

[huestack]

ColumnDefinitions as a StaticResource throws NullReferenceException when assigning to multiple Grids.

[maxkatz6]

Never seen this application of ColumnDefinitions, but looks handy.

[workgroupengineering]

the problem is there

Avalonia/src/Avalonia.Controls/Grid.cs

Lines 177 to 183 in 262c1b0

	set
	{
	if (_extData == null) { _extData = new ExtendedData(); }
	_extData.ColumnDefinitions = value;
	_extData.ColumnDefinitions.Parent = this;
	InvalidateMeasure();
	}

exactly on line 181.

StaticResource return same instance for each grid.

two possible solutions could be:

• Deep cloning like this code:

            set
            {
                if (_extData == null) { _extData = new ExtendedData(); }
                var def = value is null
                    ? new ColumnDefinitions()
                    : new ColumnDefinitions(value.Count);
                if (value is not null)
                {
                    foreach (var item in value)
                    {
                        def.Add(new ColumnDefinition()
                        {
                            MaxWidth = item.MaxWidth,
                            MinWidth = item.MinWidth,
                            SharedSizeGroup = item.SharedSizeGroup,
                            Width = item.Width,
                        });
                    }
                }
                _extData.ColumnDefinitions = def;
                _extData.ColumnDefinitions.Parent = this;
                InvalidateMeasure();
            }

• x:Shared directive like WPF

Personally I prefer x:Shared

[rabbitism]

DefinitionBase holds many calculation and status of groups, especially SharedSizeGroup, i doubt if this is even possible.

[workgroupengineering]

Can i work on x:Shared?

[kekekeks]

Given that we already have support for resource factories for lazy resource loading, x:Shared can be implemented by calling AddNotShared (or smth) instead of AddDeferred.

[timunie]

Can i work on x:Shared?

I talked to the team and we would be happy if you help us to get this implemented.

Nikita [15.05.2024 09:29]
it shouldn't be that hard to implement since we already have resource factories for lazy resource loading

Nikita [15.05.2024 09:30]
so it might be implemented as calling AddShared instead of AddDeferred"