This might serve your purpose. The function creates an annulus object and allows you to set the linestyle and edgecolor while preserving the correct look of the annulus.
function [P] = annulus(r,R,xf,Xf,yf,Yf)
% Creates a annulus patch object and returns the handle. Input arguments
% are the inner radius, outer radius, inner x offset, outer x offset, inner
% y offset and outer Y offset. Changes to the edgecolor and linestyle are
% allowed, and will preserve the correct look of the annulus
t = linspace(0,2*pi,200);
x = xf + r*cos(t);
y = yf + r*sin(t);
X = Xf + R*cos(t);
Y = Yf + R*sin(t);
P = patch([x X],[y Y],[1,.5,.5],'linestyle','non','facealph',.5);
L(1) = line(x,y,'color','k');
L(2) = line(X,Y,'color','k');
axis equal
plistener(P,'edgecolor',@edgec) % listeners for changes to props.
plistener(P,'linestyle',@lnstl)
function [] = plistener(ax,prp,func)
% Sets the properties. From proplistener by Yair Altman.
psetact = 'PropertyPostSet';
hC = handle(ax);
hSrc = hC.findprop(prp);
hl = handle.listener(hC, hSrc, psetact, {func,ax});
p = findprop(hC, 'Listeners__');
if isempty(p)
p = schema.prop(hC, 'Listeners__', 'handle vector');
set(p,'AccessFlags.Serialize', 'off', ...
'AccessFlags.Copy', 'off',...
'FactoryValue', [], 'Visible', 'off');
end
hC.Listeners__ = hC.Listeners__(ishandle(hC.Listeners__));
hC.Listeners__ = [hC.Listeners__; hl];
end
function [] = edgec(varargin)
St = get(varargin{3},'edgecolor');
set(L,'color',St)
end
function [] = lnstl(varargin)
St = get(varargin{3},'linestyle');
set(varargin{3},'linestyle','none')
set(L,'linestyle',St)
end
end
