vb.net - MouseLeave and Enter on Form -

i trying make form fade away taskbar if user not hovering on form mouse. (the form contains hyperlinks). on adverse, want form reset original position if mouse comes form. however, whatever reason, seems thought enter , leave evens fire in sync when either occurs. if leave form mouse, both events fire. if enter form, both events fire. wrong?

sub formleave()         mouseform = false         until y = screen.primaryscreen.workingarea.height + 50             sleep(10)             y = y + 1             me.location = new point(x, y)             if mouseform = true                 exit sub             end if         loop             end sub      sub formenter()         mouseform = true         me.visible = true         x = screen.primaryscreen.workingarea.width - me.width         y = screen.primaryscreen.workingarea.height - me.height         me.location = new point(x, y)            end sub 

animation best done timer (i.e. event driven) rather sleeping.

you have make sure cursor has left boundary of form, leave event fired on form when mouse enters control within form.

i added longer delay when mouse leaves form otherwise annoying.

to demonstrate, use code new windows forms project. add controls form if want confirm not misbehave when put mouse on control on form.

public class form1      dim x integer     dim y integer     dim tim timer      sub moveformaway(sender object, e eventargs)         ' called on timer tick event         dim desty = screen.primaryscreen.workingarea.height - 100          if y >= desty             tim.enabled = false             exit sub         end if          ' interval form position changes         tim.interval = 10         y += 2         me.location = new point(x, y)      end sub      sub formbodyleave(sender object, e eventargs)         ' if mouse has not left outside of form,         ' i.e. has entered control on form, exit:         if me.clientrectangle.contains(pointtoclient(cursor.position))             exit sub         end if          if tim nothing orelse not tim.enabled             x = me.location.x             y = me.location.y             tim = new timer             ' initial interval until form starts running away             tim.interval = 1000             addhandler tim.tick, addressof moveformaway             tim.enabled = true         end if      end sub      sub formbodyenter(sender object, e eventargs)         if tim isnot nothing             tim.enabled = false         end if          movetodefaultposition()      end sub      sub addformdisappearinghandlers()         addhandler me.mouseenter, addressof formbodyenter         addhandler me.mouseleave, addressof formbodyleave      end sub      sub movetodefaultposition()         x = screen.primaryscreen.workingarea.width - me.width         y = screen.primaryscreen.workingarea.height - me.height         me.location = new point(x, y)      end sub      private sub form1_load(sender object, e eventargs) handles mybase.load         movetodefaultposition()         addformdisappearinghandlers()      end sub      private sub form1_formclosing(sender object, e formclosingeventargs) handles mybase.formclosing         ' tidy up.         if tim isnot nothing             tim.dispose()         end if      end sub  end class