DataGrid Row Selection Color Lost

[WolfJMZ]

Another bug I found is that the Selection color is Lost when BOTH RowBackground and AlternatingRowBackground are set to different brushes. There is no mousehover color either, same with mousedown and selected. This behavior also occurs when only AlternatingRowBackground is set.

[punker76]

@jammerxd which version? short sample?

[WolfJMZ]

Version 1.1.3.0 And the mouseover, selected, mousedown colors all disappear when I set the alternating row color to any of the accentbrushes. The control acts as if it is disabled but I know it's not since the slectedindexchanged event fires.

[spaccabit]

The problem it's in CoerceValueCallback of DataGridRow.BackgroundProperty.

For solve the issue i have created MetroDataGridRow that inheriting from DataGridRow and override the metadata of BackgroundProperty .
Sample code:

    public class MetroDataGridRow : DataGridRow
    {
        static MetroDataGridRow()
        {

            var meta = DataGridRow.BackgroundProperty.GetMetadata(typeof(DataGridRow))
                as FrameworkPropertyMetadata;

             DataGridRow.BackgroundProperty.OverrideMetadata(typeof(MetroDataGridRow)
                , new FrameworkPropertyMetadata(meta.DefaultValue
                , Translate(meta)
                    , meta.PropertyChangedCallback
                    , new CoerceValueCallback((sender, value) =>
                        {
                            var row = sender as System.Windows.Controls.DataGridRow;
                            if (row != null 
                               && row.IsSelected == false 
                               && row.IsMouseOver == false)
                            {
                                return meta.CoerceValueCallback(sender, value);
                            }
                            return value;
                        })
                    ));

        }

        private static FrameworkPropertyMetadataOptions Translate(FrameworkPropertyMetadata meta)
        {
            var flag = FrameworkPropertyMetadataOptions.None;
            if (meta.AffectsArrange)
            {
                flag |= FrameworkPropertyMetadataOptions.AffectsArrange;
            }
            if (meta.AffectsMeasure)
            {
                flag |= FrameworkPropertyMetadataOptions.AffectsMeasure;
            }
            if (meta.AffectsParentArrange)
            {
                flag |= FrameworkPropertyMetadataOptions.AffectsParentArrange;
            }
            if (meta.AffectsParentMeasure)
            {
                flag |= FrameworkPropertyMetadataOptions.AffectsParentMeasure;
            }
            if (meta.AffectsRender)
            {
                flag |= FrameworkPropertyMetadataOptions.AffectsRender;
            }
            if (meta.BindsTwoWayByDefault)
            {
                flag |= FrameworkPropertyMetadataOptions.BindsTwoWayByDefault;
            }
            if (meta.Inherits)
            {
                flag |= FrameworkPropertyMetadataOptions.Inherits;
            }
            if (meta.Journal)
            {
                flag |= FrameworkPropertyMetadataOptions.Journal;
            }
            if (meta.OverridesInheritanceBehavior)
            {
                flag |= FrameworkPropertyMetadataOptions.OverridesInheritanceBehavior;
            }
            if (meta.SubPropertiesDoNotAffectRender)
            {
                flag |= FrameworkPropertyMetadataOptions.SubPropertiesDoNotAffectRender;
            }
            return flag;
        }
    }

    public class MetroDataGrid:DataGrid
    {
        protected override System.Windows.DependencyObject GetContainerForItemOverride()
        {
            return new MetroDataGridRow();
        }
    }

And it use it

<Controls:MetroDataGrid Style="{StaticResource MetroDataGrid}" ...>
...
</Controls:MetroDataGrid>
'''

[spaccabit]

I've found another more smarter solution.
You don't setting AlternatingRowBackground , set AlternationCount at 2 and RowStyle like this:

    <Style BasedOn="{StaticResource MetroDataGridRow}" TargetType="DataGridRow">
        <Style.Triggers>
            <Trigger Property="ItemsControl.AlternationIndex" Value="1">
                <Setter Property="Background" Value="Red" />
            </Trigger>
            <MultiTrigger>
                <MultiTrigger.Conditions>
                    <Condition Property="ItemsControl.AlternationIndex" Value="1" />
                    <Condition Property="IsMouseOver" Value="true" />
                </MultiTrigger.Conditions>
                <Setter Property="Background" Value="{DynamicResource AccentColorBrush}" />
            </MultiTrigger>
            <MultiTrigger>
                <MultiTrigger.Conditions>
                    <Condition Property="ItemsControl.AlternationIndex" Value="1" />
                    <Condition Property="IsSelected" Value="true" />
                </MultiTrigger.Conditions>
                <Setter Property="Background" Value="{DynamicResource AccentColorBrush}" />
            </MultiTrigger>
        </Style.Triggers>
    </Style>