swt - Eclipse GEF - Select figures -

i using gef framework show network of connected nodes. have topeditpart diagram , 1 editpart each node , connections. diagram rendering properly. need select node , outgoing connections , connected nodes should change different color. started off @ editpolicies gef provides, have no clue edit policy use highlight figure ie., show selection feedback. in regard appreciated. have tried:

i created class extending xylayouteditpolicy , installed on rooteditpart

public class basicxylayouteditpolicy extends xylayouteditpolicy {     protected command createaddcommand(editpart child, object constraint) {         return null;     }      protected command createchangeconstraintcommand(editpart child, object constraint) {         return null;     }      protected command getcreatecommand(createrequest request) {         return null;     }      protected editpolicy createchildeditpolicy(editpart child) {         return new noderesizableeditpolicy();      }      protected command getdeletedependantcommand(request request) {         return null;     }      public editpart gettargeteditpart(request request) {         editpart targeteditpart = gethost(); // guessed that...         return targeteditpart;     } } 

installed on root editpart

protected void createeditpolicies() {     installeditpolicy(editpolicy.layout_role, new basicxylayouteditpolicy()); } 

now create new class nodeselectioneditpolicy extends selectioneditpolicy

public class nodeselectioneditpolicy extends selectioneditpolicy {      @override     protected void hideselection() {         gethostfigure().setbackgroundcolor(display.getdefault().getsystemcolor(swt.color_green));     }      @override     protected void showselection() {         gethostfigure().setbackgroundcolor(display.getdefault().getsystemcolor(swt.color_dark_red));     } } 

next installing policy onto node edit parts

protected void createeditpolicies() {     installeditpolicy(editpolicy.selection_feedback_role, new nodeselectioneditpolicy()); } 

when execute code, nothing seems happen ie., no visual selection feedback happens. missing ? need implement method of nodeselectioneditpolicy ?

extending selectioneditpolicy right way go , should working (in code change color of selected figure).

the problem figure not have background color therefore changing background color doesn't much. try changing foreground color.