protected FieldRange getSelectedRangeContaining(int rowIndex) {
		FieldRange fieldRange = null;
		if (selection.containsEntirely(BigInteger.valueOf(rowIndex))) {
			// Get the size of the selection range we are in.
			int numRanges = selection.getNumRanges();
			for (int i = 0; i < numRanges; i++) {
				FieldRange range = selection.getFieldRange(i);
				if ((range.getStart().getIndex().intValue() <= rowIndex) &&
					(rowIndex < range.getEnd().getIndex().intValue())) {
					fieldRange = range;
					break;
				}
			}
		}
		return fieldRange;
	}
Returns the selection range containing the specified row index if there is one that contains
it. Otherwise, returns null.

@param rowIndex the row index
@return the range or null
Ghidra/Features/Base/src/main/java/ghidra/app/plugin/core/compositeeditor/CompositeViewerModel.java