Java™ Application Development on Linux - Dator

16.7 Getting Down to Cases: Designing a GUI for BudgetPro365JLabel retval = new JLabel();// ...if (row == 2) {retval.setBackground(Color.GREEN);} else {retval.setBackground(Color.WHITE);}return retval;The full implementation of a renderer can also take into account whetheror not the cell is selected and/or has focus. This has to do with enabling mouseclicks to select either that particular cell or the row or column containing thatcell. You will likely want to render the cell differently (with a darker color,perhaps) to show that it has been selected. Whatever the renderer, you set upand then return a GUI component whose attributes (font, color, size, andso on) are used to display that cell.We hope you get the idea—there is a lot more to renderers than we willcover here. The Java Tutorial covers them more, and the Javadoc pages havesome introduction, too.Similar to renderers are editors. When a user clicks in a table cell, the tablemay allow him or her to edit its contents. A cell editor is needed to do that,and then your program needs to do something with the value that was entered.For our BudgetPro example we avoid this complexity by disallowing the userto enter anything into the table—our table is for display only. We do this onlines 187–191 by overriding the method isCellEditable() to always returnfalse:187 public boolean188 isCellEditable(int row, int col)189 {190 return false;191 } // is CellEditableNotice that the method is passed the row and column means that youcould make some cells editable and some not.16.7.2.10 Selection ListenersLet’s look at the last part of the table that we implement for BudgetPro:194 list.setSelectionMode(ListSelectionModel.SINGLE_SELECTION);