Merge and Unmerge Cells

We can use Range API to merge (or unmerge) a range of cells and detect merged cells existed in a given range:

//true for merging horizontally, false is to merge all together
range.merge(false);

range.unmerge();

//returns true if any merged cell is inside this range
boolean hasMergedCell = range.hasMergedCell();
//returns true if entire range is a merged cell.
boolean isMergedCell = range.isMergedCell();

CellRegion region = range.getMergedRegion();

We still can use CellOperationUtil to achieve this and it provides 3 APIs for 4 actions corresponding to merge function of Spreadsheet's toolbar including "Merge & Center", "Merge Across", "Merge Cells", and "Unmerge". Each method requires a Range to represent the target cells you are going to merge. The usages are showed as follows:

API usage about merging

public class MergeComposer extends SelectorComposer<Component> {

	@Wire
	private Spreadsheet ss;

	@Listen("onClick = #mergeCenterButton")
	public void mergeCenter() {
		CellOperationUtil.toggleMergeCenter(getSelectedRange());
	}
	
	@Listen("onClick = #mergeAcrossButton")
	public void mergeAcross() {
		CellOperationUtil.merge(getSelectedRange(), true);
	}
	
	@Listen("onClick = #mergeButton")
	public void merge() {
		CellOperationUtil.merge(getSelectedRange(), false);
	}
	
	@Listen("onClick = #unmergeButton")
	public void unmerge() {
		CellOperationUtil.unmerge(getSelectedRange());
	}
	
	private Range getSelectedRange(){
		return Ranges.range(ss.getSelectedSheet(), ss.getSelection());
	}

	//omitted codes...
}

All source code listed in this book is at Github.