Eclipse RCP : How to check state(toggle) of a menu items or toolbar items inside handlers

In Eclipse RCP there are at-least two different ways we  can check the state of a menu item or  a toolbar item inside a handlers execute method :

Option 1 :

ICommandService service =(ICommandService) PlatformUI.getWorkbench().getService(ICommandService.class);

Command command = service.getCommand("org.eclipse.example.command.toggle");

State state = command.getState("org.eclipse.example.command.toggleState");

System.out.println(state.getValue());

//state.setValue(!(Boolean) state.getValue());

Option 2:

   @Override

    public Object execute(ExecutionEvent event) throws ExecutionException {

   

   

        Event selEvent = (Event) event.getTrigger();

        Widget widget =  selEvent.widget;

        if (widget instanceof ToolItem) {        

        isSelected = ((ToolItem)widget).getSelection();

}else {

isSelected = ((MenuItem)widget).getSelection();

}

}

Eclipse RCP : How to check a view is currenlty visible

If we need to check whether a view currently available or visible we can use following code :

Boolean result = false;

IViewReference viewReferene =  PlatformUI.getWorkbench().getActiveWorkbenchWindow().getActivePage().findViewReference("my_view_id");


if (viewReferene != null) {
result = true;
}

How to Enable and Disable VNC server password authentication in cent os

You can switch between password and non password mode by:

# vi /etc/X11/xorg.conf  (enable password)

[..]

    #Option "SecurityTypes" "None"

    Option "SecurityTypes" "VncAuth"

    Option "UserPasswdVerifier" "VncAuth"

    Option "PasswordFile" "/root/.vnc/passwd"

[..]

# vi /etc/X11/xorg.conf  (disable password)

[..]

    Option "SecurityTypes" "None"

    #Option "SecurityTypes" "VncAuth"

    #Option "UserPasswdVerifier" "VncAuth"

    #Option "PasswordFile" "/root/.vnc/passwd"

[..]

Restart X for change to take effect:

# init 3   (wait a few seconds - )

# init 5

after enabling the password: 

You should be able to type ”vncpasswd” from the terminal as root. This will enable you to type in a new password for the VNC connection.