c# - WPF DataGrid wrapped by Grid won't scroll horizontally -

i'm trying make datagrid scroll horizontally when window small display of columns. i'm using grids control positioning of elements. can explain why scrollbar isn't appearing , how can fix it? prefer xaml solution if possible.

here complete code. feel free critique weird see because i'm new wpf.

<window x:class="fblam.mainwindow"     xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"     xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"     xmlns:d="http://schemas.microsoft.com/expression/blend/2008"     xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"     xmlns:local="clr-namespace:fblam"     mc:ignorable="d"     title="mainwindow" width="800" height="600"> <grid>     <grid.rowdefinitions>         <rowdefinition height="auto" />         <rowdefinition height="*" />     </grid.rowdefinitions>     <grid.columndefinitions>         <columndefinition width="*" />     </grid.columndefinitions>     <menu grid.row="0" grid.column="0" ismainmenu="true" height="20" verticalalignment="top">         menu goes here     </menu>     <grid grid.row="1" grid.column="0" horizontalalignment="center" background="#fff0f0f0">         <grid.rowdefinitions>             <rowdefinition height="auto" />             <rowdefinition height="*" />         </grid.rowdefinitions>         <grid.columndefinitions>             <columndefinition width="*" />             <columndefinition width="auto" />             <columndefinition width="*" />         </grid.columndefinitions>         <stackpanel grid.column="1" grid.row="0" orientation="horizontal" verticalalignment="stretch" horizontalalignment="stretch">             <button content="button1" horizontalalignment="left" padding="10,2" verticalalignment="center"/>             <button content="button2" horizontalalignment="left" padding="10,2" verticalalignment="center" margin="10,0,0,0"/>         </stackpanel>         <datagrid                grid.column="1"                grid.row="1"                x:name="memberdata"                autogeneratecolumns="false"                isreadonly="false"                canuserresizecolumns="true"                canuseraddrows="true"                canusersortcolumns="true"                itemssource="{binding}"                selectionmode="single"                headersvisibility="column"                horizontalcontentalignment="stretch"                verticalcontentalignment="stretch"                borderthickness="0"                margin="0"                gridlinesvisibility="horizontal"               scrollviewer.cancontentscroll="true"                scrollviewer.horizontalscrollbarvisibility="visible">             <datagrid.columns>                 <datagridtextcolumn header="id" binding="{binding id}" />                 <datagridtextcolumn header="first name" binding="{binding firstname}" />                 <datagridtextcolumn header="last name" binding="{binding lastname}" />                 <datagridtextcolumn header="school" binding="{binding school}" />                 <datagridtextcolumn header="state" binding="{binding state}" />                 <datagridhyperlinkcolumn header="email" binding="{binding email}" />                 <datagridtextcolumn header="year joined" binding="{binding yearjoined}" />                 <datagridtextcolumn header="grade" binding="{binding grade}" />                 <datagridcheckboxcolumn header="active" binding="{binding active}" />                 <datagridtextcolumn header="amount owed" binding="{binding amountowed, stringformat=c}" />             </datagrid.columns>         </datagrid>     </grid> </grid> 

why have columndefinition bound actualwidth of datagrid? remove that. also, move scrollviewer properties datagrid itself.

<window x:class="myproject.mainwindow"         xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"         xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"         xmlns:d="http://schemas.microsoft.com/expression/blend/2008"         xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"         xmlns:local="clr-namespace:myproject"         mc:ignorable="d"         title="mainwindow" width="800" height="600">     <grid>         <grid.rowdefinitions>             <rowdefinition height="auto" />             <rowdefinition height="*" />         </grid.rowdefinitions>         <menu grid.row="0" ismainmenu="true" height="20" verticalalignment="top">             //menu items         </menu>         <grid grid.row="1" horizontalalignment="stretch" background="#fff0f0f0">             <grid.rowdefinitions>                 <rowdefinition height="auto" />                 <rowdefinition height="*" />             </grid.rowdefinitions>             <grid.columndefinitions>                 <columndefinition width="*" />                 <columndefinition width="auto" />                 <columndefinition width="*" />             </grid.columndefinitions>             <stackpanel grid.column="1" grid.row="0" orientation="horizontal" verticalalignment="stretch" horizontalalignment="stretch">                 <button content="button1" horizontalalignment="left" padding="10,2" verticalalignment="center"/>                 <button content="button2" horizontalalignment="left" padding="10,2" verticalalignment="center" margin="10,0,0,0"/>             </stackpanel>             <datagrid grid.column="1"                        grid.row="1"                        autogeneratecolumns="false"                        isreadonly="false"                        canuserresizecolumns="true"                        canuseraddrows="true"                        canusersortcolumns="true"                        itemssource="{binding}"                        selectionmode="single"                        headersvisibility="column"                        horizontalcontentalignment="stretch"                        verticalcontentalignment="stretch"                        borderthickness="0"                        margin="0"                        gridlinesvisibility="horizontal"                       scrollviewer.cancontentscroll="true"                        scrollviewer.horizontalscrollbarvisibility="visible" >                 <datagrid.columns>                     //10 columns here                 </datagrid.columns>             </datagrid>         </grid>     </grid> </window>