www.gusucode.com > matlab从零到进阶程序与数据 > matlab从零到进阶程序与数据/第5章 图形用户界面（GUI）编程/ex54_2.m

    %创建界面窗口，不包含工具条
h0=figure('toolbar','none',...
    'position',[200 150 450 250],...
    'name','ex54_2',...
    'numbertitle','off');
%在窗口中绘制正弦曲线
x=0:0.5:2*pi;
y=sin(x);
h=plot(x,y);
grid on
%创建静态文本控件
hm=uicontrol(h0,'style','text',...
    'string',...
    '绘图函数',...
    'position',[380 180 50 20]);
%创建弹出式菜单控件，并初始化其string属性值
hm=uicontrol(h0,'style','popupmenu',...
    'string',...
    'sin(x)|cos(x)|sin(x)+cos(x)',...
    'position',[380 150 50 20]);
%设置弹出式菜单的第一项为默认选项
set(hm,'value',1)
%定义弹出式菜单的callback，为字符数组
my_callback=[...
    'v=get(hm,''value'');,',...
    'switch v,',...
    'case 1,',...
    'delete(h),',...
    'y=sin(x);,',...
    'h=plot(x,y);,',...
    'grid on,',...
    'case 2,',...
    'delete(h),',...
    'y=cos(x);,',...
    'h=plot(x,y);,',...
    'grid on,',...
    'case 3,',...
    'delete(h),',...
    'y=sin(x)+cos(x);,',...
    'h=plot(x,y);,',...
    'grid on,',...
    'end'];
%设置弹出式菜单的callback属性值
set(hm,'callback',my_callback)
%设置坐标轴的位置和大小，坐标轴对象的units属性缺省值为normalized
set(gca,'position',[0.2 0.2 0.6 0.6])