improved datagrid

src/Core_30/HandyControl_Core_30/Themes/Styles/DataGrid.xaml

@@ -257,6 +257,7 @@
         <Setter Property="controls:DataGridAttach.EditingComboBoxColumnStyle" Value="{StaticResource ComboBoxBaseStyle}"/>
         <Setter Property="controls:DataGridAttach.CheckBoxColumnStyle" Value="{StaticResource CheckBoxBaseStyle}"/>
         <Setter Property="controls:DataGridAttach.EditingCheckBoxColumnStyle" Value="{StaticResource CheckBoxBaseStyle}"/>
+        <Setter Property="controls:DataGridAttach.ApplyDefaultStyle" Value="True"/>
         <Setter Property="Template">
             <Setter.Value>
                 <ControlTemplate TargetType="DataGrid">

src/Net_40/HandyControl_Net_40/Themes/Styles/DataGrid.xaml

@@ -258,6 +258,7 @@
         <Setter Property="controls:DataGridAttach.EditingComboBoxColumnStyle" Value="{StaticResource ComboBoxBaseStyle}"/>
         <Setter Property="controls:DataGridAttach.CheckBoxColumnStyle" Value="{StaticResource CheckBoxBaseStyle}"/>
         <Setter Property="controls:DataGridAttach.EditingCheckBoxColumnStyle" Value="{StaticResource CheckBoxBaseStyle}"/>
+        <Setter Property="controls:DataGridAttach.ApplyDefaultStyle" Value="True"/>
         <Setter Property="Template">
             <Setter.Value>
                 <ControlTemplate TargetType="DataGrid">

src/Net_GE45/HandyControl_Net_GE45/Themes/Styles/DataGrid.xaml

@@ -257,6 +257,7 @@
         <Setter Property="controls:DataGridAttach.EditingComboBoxColumnStyle" Value="{StaticResource ComboBoxBaseStyle}"/>
         <Setter Property="controls:DataGridAttach.CheckBoxColumnStyle" Value="{StaticResource CheckBoxBaseStyle}"/>
         <Setter Property="controls:DataGridAttach.EditingCheckBoxColumnStyle" Value="{StaticResource CheckBoxBaseStyle}"/>
+        <Setter Property="controls:DataGridAttach.ApplyDefaultStyle" Value="True"/>
         <Setter Property="Template">
             <Setter.Value>
                 <ControlTemplate TargetType="DataGrid">

src/Shared/HandyControl_Shared/Controls/Attach/DataGridAttach.cs

@@ -8,6 +8,44 @@ namespace HandyControl.Controls
 {
     public class DataGridAttach
     {
+        public static readonly DependencyProperty ApplyDefaultStyleProperty = DependencyProperty.RegisterAttached(
+            "ApplyDefaultStyle", typeof(bool), typeof(DataGridAttach), new PropertyMetadata(ValueBoxes.FalseBox, OnApplyDefaultStyleChanged));
+
+        private static void OnApplyDefaultStyleChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
+        {
+            var grid = (DataGrid)d;
+            if ((bool)e.NewValue)
+            {
+                if (grid.AutoGenerateColumns)
+                {
+                    grid.AutoGeneratedColumns += Grid_AutoGeneratedColumns;
+                    return;
+                }
+
+                UpdateTextColumnStyles(grid);
+                UpdateComboBoxColumnStyles(grid);
+                UpdateCheckBoxColumnStyles(grid);
+            }
+            else
+            {
+                grid.AutoGeneratedColumns -= Grid_AutoGeneratedColumns;
+            }
+        }
+
+        private static void Grid_AutoGeneratedColumns(object sender, System.EventArgs e)
+        {
+            var grid = (DataGrid)sender;
+            UpdateTextColumnStyles(grid);
+            UpdateComboBoxColumnStyles(grid);
+            UpdateCheckBoxColumnStyles(grid);
+        }
+
+        public static void SetApplyDefaultStyle(DependencyObject element, bool value)
+            => element.SetValue(ApplyDefaultStyleProperty, value);
+
+        public static bool GetApplyDefaultStyle(DependencyObject element)
+            => (bool) element.GetValue(ApplyDefaultStyleProperty);
+
         public static readonly DependencyProperty TextColumnStyleProperty = DependencyProperty.RegisterAttached(
             "TextColumnStyle", typeof(Style), typeof(DataGridAttach), new PropertyMetadata(default(Style), OnTextColumnStyleChanged));