JQGrid 多级 Header Group 问题

最近在用jqgrid，但是需要对Header进行多级分组，结果出现下面现象：

标红的地方可以看到，描绘完全错了，调试发现时jqgrid 居然把header group 中增长的行数写死为 2，

当header高度大于两行时就可能出现问题，为了不修改jqgrid源文件，我把jqgrid问题函数copy重新修改了一下，

然后动态替换掉jqgrid原有的方法，就OK了~

修改方法如下：

(function(){
	$.fn.jqGrid.setGroupHeaders = function ( o ) {
		o = $.extend({
			useColSpanStyle :  false,
			depth : 2,
			groupHeaders: []
		},o  || {});
		return this.each(function(){
			this.p.groupHeader = o;
			var ts = this,
			i, cmi, skip = 0, $tr, $colHeader, th, $th, thStyle,
			iCol,
			cghi,
			//startColumnName,
			numberOfColumns,
			titleText,
			cVisibleColumns,
			colModel = ts.p.colModel,
			cml = colModel.length,
			ths = ts.grid.headers,
			$htable = $("table.ui-jqgrid-htable", ts.grid.hDiv),
			$trLabels = $htable.children("thead").children("tr.ui-jqgrid-labels:last").addClass("jqg-second-row-header"),
			$thead = $htable.children("thead"),
			$theadInTable,
			$firstHeaderRow = $htable.find(".jqg-first-row-header");
			if($firstHeaderRow[0] === undefined) {
				$firstHeaderRow = $('', {role: "row", "aria-hidden": "true"}).addClass("jqg-first-row-header").css("height", "auto");
			} else {
				$firstHeaderRow.empty();
			}
			var $firstRow,
			inColumnHeader = function (text, columnHeaders) {
				var length = columnHeaders.length, i;
				for (i = 0; i < length; i++) {
					if (columnHeaders[i].startColumnName === text) {
						return i;
					}
				}
				return -1;
			};

			$(ts).prepend($thead);
			$tr = $('', {role: "rowheader"}).addClass("ui-jqgrid-labels jqg-third-row-header");
			for (i = 0; i < cml; i++) {
				th = ths[i].el;
				$th = $(th);
				cmi = colModel[i];
				// build the next cell for the first header row
				thStyle = { height: '0px', width: ths[i].width + 'px', display: (cmi.hidden ? 'none' : '')};
				$("", {role: 'gridcell'}).css(thStyle).addClass("ui-first-th-"+ts.p.direction).appendTo($firstHeaderRow);

				th.style.width = ""; // remove unneeded style
				iCol = inColumnHeader(cmi.name, o.groupHeaders);
				if (iCol >= 0) {
					cghi = o.groupHeaders[iCol];
					numberOfColumns = cghi.numberOfColumns;
					titleText = cghi.titleText;

					// caclulate the number of visible columns from the next numberOfColumns columns
					for (cVisibleColumns = 0, iCol = 0; iCol < numberOfColumns && (i + iCol < cml); iCol++) {
						if (!colModel[i + iCol].hidden) {
							cVisibleColumns++;
						}
					}

					// The next numberOfColumns headers will be moved in the next row
					// in the current row will be placed the new column header with the titleText.
					// The text will be over the cVisibleColumns columns
					$colHeader = $('').attr({role: "columnheader"})
						.addClass("ui-state-default ui-th-column-header ui-th-"+ts.p.direction)
						.css({'height':'22px', 'border-top': '0 none'})
						.html(titleText);
					if(cVisibleColumns > 0) {
						$colHeader.attr("colspan", String(cVisibleColumns));
					}
					if (ts.p.headertitles) {
						$colHeader.attr("title", $colHeader.text());
					}
					// hide if not a visible cols
					if( cVisibleColumns === 0) {
						$colHeader.hide();
					}

					$th.before($colHeader); // insert new column header before the current
					$tr.append(th);         // move the current header in the next row

					// set the coumter of headers which will be moved in the next row
					skip = numberOfColumns - 1;
				} else {
					if (skip === 0) {
						if (o.useColSpanStyle) {
							// expand the header height to two rows
							$th.attr("rowspan", o.depth + "");
						} else {
							$('', {role: "columnheader"})
								.addClass("ui-state-default ui-th-column-header ui-th-"+ts.p.direction)
								.css({"display": cmi.hidden ? 'none' : '', 'border-top': '0 none'})
								.insertBefore($th);
							$tr.append(th);
						}
					} else {
						// move the header to the next row
						//$th.css({"padding-top": "2px", height: "19px"});
						$tr.append(th);
						skip--;
					}
				}
			}
			$theadInTable = $(ts).children("thead");
			$theadInTable.prepend($firstHeaderRow);
			$tr.insertAfter($trLabels);
			$htable.append($theadInTable);

			if (o.useColSpanStyle) {
				// Increase the height of resizing span of visible headers
				$htable.find("span.ui-jqgrid-resize").each(function () {
					var $parent = $(this).parent();
					if ($parent.is(":visible")) {
						this.style.cssText = 'height: ' + $parent.height() + 'px !important; cursor: col-resize;';
					}
				});

				// Set position of the sortable div (the main lable)
				// with the column header text to the middle of the cell.
				// One should not do this for hidden headers.
				$htable.find("div.ui-jqgrid-sortable").each(function () {
					var $ts = $(this), $parent = $ts.parent();
					if ($parent.is(":visible") && $parent.is(":has(span.ui-jqgrid-resize)")) {
						$ts.css('top', ($parent.height() - $ts.outerHeight()) / 2 + 'px');
					}
				});
			}

			$firstRow = $theadInTable.find("tr.jqg-first-row-header");
			$(ts).bind('jqGridResizeStop.setGroupHeaders', function (e, nw, idx) {
				$firstRow.find('th').eq(idx).width(nw);
			});
		});				
	}
})();

这样，在使用时传入一个depth 就可以了，默认是2，和jqgrid写死的相同。

用法如下：

grid.jqGrid('setGroupHeaders', {
				depth : 3,
				useColSpanStyle : true,
				groupHeaders : headers
			});