Scroll trough some pages and then count the number of row nodes. We are instantiating the grid with 10 rows per page, and caching at most 20 rows. So if this policy works, you should never see a number bigger than 20!
DEPRECATED: dojox.grid.DataGrid::attr() is deprecated. Use get() or set() instead, called from function(){if(this.scrollboxNode){this.windowHeight=this.scrollboxNode.clientHeight;}for(var i=0;i<this.colCount;i++){dojox.grid.util.setStyleHeightPx(this.contentNodes[i],Math.max(1,this.height));}var _23c=(!this._invalidating);if(!_23c){var ah=this.grid.attr("autoHeight");if(typeof ah=="number"&&ah<=Math.min(this.rowsPerPage,this.rowCount)){_23c=true;}}if(_23c){this.needPage(this.page,this.pageTop);}var _23d=(this.page<this.pageCount-1)?this.rowsPerPage:((this.rowCountundefinedhis.rowsPerPage)||this.rowsPerPage);var _23e=this.getPageHeight(this.page);this.averageRowHeight=(_23e>0&&_23d>0)?(_23e/_23d):0;} -- will be removed in version: 2.0
DEPRECATED: dojox.grid.DataGrid::attr() is deprecated. Use get() or set() instead, called from function(_241,_242){if(this.pageExists(_241)){var oh=this.getPageHeight(_241);var h=(this.measurePage(_241));if(h===undefined){h=oh;}this.pageHeights[_241]=h;if(oh!=h){this.updateContentHeight(h-oh);var ah=this.grid.attr("autoHeight");if((typeof ah=="number"&&ah>this.rowCount)||(ah===true&&!_242)){this.grid.sizeChange();}else{this.repositionPages(_241);}}return h;}return 0;} -- will be removed in version: 2.0