If we move the mouse in table widget, it will show the row & column no which we selected and if we click on any cell it will emit a signal with the corresponding row & column number. And if we go beyond the maximum row and maxim column, just left click on mouse. Then it will opens a widget for entering rows and columns. This will also emit a signal with the specified rows & columns.
This table widget is similar to the icon Table on toolbar in OpenOffice.