How to add clickhandler to the subrow of the celltablebuilder - gwt-celltable

Question

I am able to build custom rows with celltablebuilder. When clicking on a particular anchor cell, I am able to build additional subrows for that row. This subrow has buttons, when clicking on the button I have do some action. I am able to add buttons with clickhandler in the subrow, but when clicking on the button nothing is happening clickhandler is not firing.
Can anybody please help.
protected void buildRowImpl(GridDTO rowValue, int absRowIndex ) {
buildRows(rowValue, absRowIndex, true);
if (showingFriends.contains(rowValue.getComponentId())) {
buildAdditonalRows( absRowIndex, gridDTO);
}
}
private void buildAdditonalRows(int index, GridDTO rowValue, ){
TableRowBuilder row = startRow();
td = row.startTD();
if(rowValue.getXpath() != null){
//td.text(rowValue.getXpath());
renderCell(td, createContext(1), cellTable.getColumn(1), rowValue);
}else{
td.text("");
}
td.endTD();
td = row.startTD();
Button button = new Button ();
button.setText("Save");
button.addClickHandler(new ClickHandler() {
#Override
public void onClick(ClickEvent event) {
Window.alert("ssss");
}
});
DivBuilder div = td.startDiv();
div.html(new afeHtmlBuilder().appendHtmlConstant(button.toString()).toSafeHtml());
div.end();
td.endTD();
row.endTR();
}

Answer 1

CellPreviewEvent provides subindex. You can use it to get subrow value.
Example usage :
dataGrid.addCellPreviewHandler(new CellPreviewEvent.Handler<TreeItem>() {
#Override
public void onCellPreview(final CellPreviewEvent<TreeItem> event) {
if(event.getNativeEvent().getType().equals(BrowserEvents.CLICK)){
if(event.getContext().getSubIndex()>0){
event.getValue().getChild(event.getContext().getSubIndex()-1);
}
}
}
});
Or you can provide custom CellPreviewEvent.Handler implementation with selectionMode. For more details you can look at AbstractHasData

Answer 2

I had a similar situation where i needed a widget inside a cell to listen for click events... What i found out is that the widget doesn't respond to events once you inserted it into a cell (In other words, only the actual HTML that makes up for the widget gets put into the cell, any kind of event handling isn't included). The work around is to add the events to the Cell (You can make a custom cell class for that particular cell-widget and override OnBrowserEvent to listen for events.)
See GWT: On adding custom widget to celltable losing events of the custom widgets for a more eloquent explanation and example code.