We are working on RCP4 envelopment and we are trying to implement about action inside menu bar. In RCP 3 application IworkbenchAction used to create this type of action but we don't have similar feature in RCP4 . Could you please some one help on this. Thanks in advance
There is no default About dialog in a pure e4 application you have to write your own. One reason for this is that the Eclipse RCP 3 About dialog depends heavily on the 'p2' update system - many e4 RCPs don't need to include the p2 plugins.
So you just use a normal HandledMenuItem to connect to a command. By convention the command should have the id org.eclipse.ui.help.aboutAction - this will allow Eclipse to move the menu to the correct place on macOS.