https://sourceforge.net/tracker/?func=detail&aid=3080873&group_id=152762&atid=785194

Enable the default sorting of grid is very simple and easy,
but adding menupopup="auto" to the columns will make it a nightmare

users can NOT disable the grouping function unless writing some code to control the grid

then who would like to use menupopup="auto" ??

<grid>
<columns menupopup="auto">
<column label="Author" sort="auto" />
<column label="Title" sort="auto" />
<column label="Publisher" sort="auto" />
<column label="Hardcover" sort="auto" />
</columns>
<rows>
<row>
<label value="Philip Hensher" />
<label value="The Northern Clemency" />
<label value="Knopf (October 30, 2008)" />
<label value="608 pages" />
</row>
<row>
<label value="Philip Hensher" />
<label value="The Fit" />
<label value="HarperPerennial (April 4, 2005)" />
<label value="240 pages" />
</row>
<row>
<label value="Philip Hensher" />
<label value="Kitchen Venom" />
<label value="Flamingo (May 19, 2003)" />
<label value="336 pages" />
</row>
<row>
<label value="Michael Greenberg" />
<label value="Hurry Down Sunshine" />
<label value="Other Press (September 9, 2008)" />
<label value="240 pages" />
</row>
<row>
<label value="Michael Greenberg" />
<label value="Painless Vocabulary (Painless)" />
<label value="Barron's Educational Series (September 1, 2001)" />
<label value="292 pages" />
</row>
<row>
<label value="Rick Perlstein" />
<label value="Nixonland: The Rise of a President and the Fracturing of America" />
<label value="Scribner; 1st Scribner Hardcover Ed edition (May 13, 2008)" />
<label value="896 pages" />
</row>
<row>
<label value="Rick Perlstein" />
<label value="Nixonland" />
<label value="Simon & Schuster (May 13, 2008)" />
<label value="896 pages" />
</row>
</rows>
</grid>