MahApps.Metro - DataGridHelper

Applies to DataGrid, DataGridRow and DataGridCell. Two halves: a few properties for the look of the grid, and a set for styling the columns WPF generates for you.

CellPadding and ColumnHeaderPadding

Layout and behaviour

Property	Type	Default
`CellPadding`	`Thickness`	`0`	padding inside every cell
`ColumnHeaderPadding`	`Thickness`	`10 0 4 0`	padding inside every column header
`SelectionUnit`	`DataGridSelectionUnit`	`FullRow`	which unit the MahApps styles draw as selected
`EnableCellEditAssist`	`bool`	`false`	a click straight onto a cell's editing control uses it right away

<DataGrid mah:DataGridHelper.CellPadding="10 6"
          mah:DataGridHelper.ColumnHeaderPadding="10 8" />

EnableCellEditAssist is the one that changes how the grid feels. It hooks PreviewMouseLeftButtonDown and, when the click landed directly on a cell's editing control, puts the cell into edit mode and passes the click on — so a check box column toggles on the first click instead of needing one to select the cell and another to hit the box. Read-only cells are left alone.

DataGridHelper.SelectionUnit is not DataGrid.SelectionUnit. The MahApps cell and row styles read the attached one to decide what to highlight; WPF's own property still decides what selection actually does. Set both when you change it.

Styling auto-generated columns

AutoGenerateColumns="True" builds columns from the bound type, which leaves nowhere to hang a style. These properties give the generated columns one, in pairs — a display style and an editing style:

Column type	Display	Editing
`DataGridCheckBoxColumn`	`AutoGeneratedCheckBoxColumnStyle`	`AutoGeneratedCheckBoxColumnEditingStyle`
`DataGridTextColumn`	`AutoGeneratedTextColumnStyle`	`AutoGeneratedTextColumnEditingStyle`
`DataGridComboBoxColumn`	`AutoGeneratedComboBoxColumnStyle`	`AutoGeneratedComboBoxColumnEditingStyle`
`DataGridNumericUpDownColumn`	`AutoGeneratedNumericUpDownColumnStyle`	`AutoGeneratedNumericUpDownColumnEditingStyle`
`DataGridHyperlinkColumn`	`AutoGeneratedHyperlinkColumnStyle`	`AutoGeneratedHyperlinkColumnEditingStyle`

<DataGrid AutoGenerateColumns="True"
          mah:DataGridHelper.AutoGeneratedTextColumnStyle="{StaticResource RightAlignedCell}" />

ColumnStylesHelper takes an IDataGridColumnStylesHelper and does the same job for cases the ten properties above do not cover — it is handed each generated column and can decide what to apply.