function set_speed(key)
%設定小球彈地速度。隸屬于 BALL_BOUNCE 函數。
uu=get(gcf,'UserData');
switch key
case 1
   uu{2}=uu{2}*0.5;
case 2
   uu{2}=uu{2}*2;
case 3
   uu{2}=0.05;
case 4
   kk=get(findobj(gcf,'Tag','lstColor'),'Value');
   switch kk
   case 1, uu{1}=[1,0,0];
   case 2, uu{1}=[0,1,0];
   case 3, uu{1}=[0,0,1];
   end   
end
if key<=3, radio_exclusive(key); end, 
set(gcf,'UserData',uu);  exec_bouncing(uu{3});
%
%------Sub Function: RADIO_EXCLUSIVE
function radio_exclusive(key)
ii=[1,2,3]; ii=ii(find(ii~=key));
h1=findobj(gcf,'Tag','rdRadio1'); 
h2=findobj(gcf,'Tag','rdRadio2'); 
h3=findobj(gcf,'Tag','rdRadio3'); 
eval(['set(h' int2str(key) ',''Value'',1)']);
for i=1:length(ii)
   eval(['set(h' int2str(ii(i)) ',''Value'',0)']);
end