Bug 210716 Support switch Text/Chart view in crosstab cell
Need crosstab UI provide support to switch between Text and Chart view in measure/aggregation cell.
xtab/org.eclipse.birt.report.item.crosstab.core/src/org/eclipse/birt/report/item/crosstab/core/de/internal/CrosstabModelUtil.java
{
		if ( crosstab == null )
			return null;
		for ( int dimensionIndex = crosstab.getDimensionCount( axisType ) - 1; dimensionIndex >= 0; dimensionIndex-- )
		{
			DimensionViewHandle dimensionView = crosstab.getDimension( axisType,
					dimensionIndex );
			for ( int levelIndex = dimensionView.getLevelCount( ) - 1; levelIndex >= 0; levelIndex-- )
			{
				return dimensionView.getLevel( levelIndex );
			}
		}
		return null;
	}
	/**
	 * Adjust measure aggregations for the given two level views.
	 * 
	 * @param crosstab
	 *            the crosstab where the leve views reside
	 * @param leftDimension
	 *            the first dimension name
	 * @param leftLevel
	 *            the first level name
	 * @param axisType
	 *            the row/column axis type for the first level view
	 * @param rightDimension
	 *            the second dimension name
	 * @param rightLevel
	 *            the second level name
	 * @param measures