关闭图形窗口会导致打开一个新的图形窗口

Question

这是一个模拟时钟。它运行完美。但是一旦我关闭时钟，另一个人影就会打开，只有时钟指针显示。这使得停止程序变得困难。如何停止程序？

x=0;y=0;r=10;
hold on;
theta = 0:pi/60:2*pi;
xc = r * cos(theta);
yc = r * sin(theta);
h = plot(xc,yc,'r','linewidth',4);
axis off
r=9; i=1;
set(gca,'FontWeight','bold');

for theta = pi/6: pi/6: 2*pi
    y1 = r * cos(theta);
    x1 = r * sin(theta);
    plot([x1/9*8 x1/9*7],[y1/9*8 y1/9*7],'color',[0 0 1])
    text(x1/9*9.5,y1/9*9.5,num2str(i),'color',[0 0 1]);
    i=i+1;
end

for theta=pi/30 : pi/30 : 2*pi
    y1 = 10 * cos(theta);
    x1 = 10 * sin(theta);
    plot([x1/9*8 x1/9*7],[y1/9*8 y1/9*7],'color',[0 0 0])
end

while(1)
    tic
    c = clock;
    c = c(1,4:6);
    minute =c(1,2); sec=c(1,3);
    if (c(1,1)>12)
       hr = c(1,1)-12;
    else
       hr = c(1,1);
    end
    min1 = ceil(minute/12);
    theta = (hr*pi)/6 + (min1*pi)/30;
    f=figure(1); hold on;
    y1 = 3 * cos(theta); Yhr = [0 y1];
    x1 = 3 * sin(theta); Xhr = [0 x1];
    hrhnd=plot(Xhr,Yhr);hold on;
    theta1 = (minute*pi)/30;
    y2 = 4.5 * cos(theta1); Ymin = [0 y2];
    x2 = 4.5 * sin(theta1); Xmin = [0 x2];
    minhnd=plot(Xmin,Ymin);
    theta2 = (sec*pi)/30;
    y3 = 5 * cos(theta2); Ysec = [0 y3];
    x3 = 5 * sin(theta2); Xsec = [0 x3];
    sechnd=plot(Xsec,Ysec);
    z=toc;
    pause(1-z);
     delete(sechnd);
     delete(minhnd);
     delete(hrhnd);
end

Answer 1

关闭窗口时停止脚本的最简单方法是在窗口仍然存在的情况下在其循环中测试脚本。

我们通过创建一个图形窗口并记录其句柄来启动脚本：

fig = figure;

接下来，在循环中，我们使用ishandle检查窗口是否仍然存在：

while(ishandle(fig))
   ...
end

---

完整程序：

x=0;y=0;r=10;
fig = figure;       %!!! NEW LINE
hold on;
theta = 0:pi/60:2*pi;
xc = r * cos(theta);
yc = r * sin(theta);
h = plot(xc,yc,'r','linewidth',4);
axis off
r=9; i=1;
set(gca,'FontWeight','bold');

for theta = pi/6: pi/6: 2*pi
    y1 = r * cos(theta);
    x1 = r * sin(theta);
    plot([x1/9*8 x1/9*7],[y1/9*8 y1/9*7],'color',[0 0 1])
    text(x1/9*9.5,y1/9*9.5,num2str(i),'color',[0 0 1]);
    i=i+1;
end

for theta=pi/30 : pi/30 : 2*pi
    y1 = 10 * cos(theta);
    x1 = 10 * sin(theta);
    plot([x1/9*8 x1/9*7],[y1/9*8 y1/9*7],'color',[0 0 0])
end

while(ishandle(fig))    %!!! UPDATED LINE
    tic
    c = clock;
    c = c(1,4:6);
    minute =c(1,2); sec=c(1,3);
    if (c(1,1)>12)
       hr = c(1,1)-12;
    else
       hr = c(1,1);
    end
    min1 = ceil(minute/12);
    theta = (hr*pi)/6 + (min1*pi)/30;
    f=figure(1); hold on;
    y1 = 3 * cos(theta); Yhr = [0 y1];
    x1 = 3 * sin(theta); Xhr = [0 x1];
    hrhnd=plot(Xhr,Yhr);hold on;
    theta1 = (minute*pi)/30;
    y2 = 4.5 * cos(theta1); Ymin = [0 y2];
    x2 = 4.5 * sin(theta1); Xmin = [0 x2];
    minhnd=plot(Xmin,Ymin);
    theta2 = (sec*pi)/30;
    y3 = 5 * cos(theta2); Ysec = [0 y3];
    x3 = 5 * sin(theta2); Xsec = [0 x3];
    sechnd=plot(Xsec,Ysec);
    z=toc;
    pause(1-z);
     delete(sechnd);
     delete(minhnd);
     delete(hrhnd);
end

---

您可以通过不删除和重新绘制手，而是更新它们的位置来改进您的程序。您可以在循环之前执行hrhnd=plot(Xhr,Yhr);，将手画在其初始位置，然后set(hrhnd,'XData',Xhr,'YData', Yhr) 更新其位置。

你也可以在画完钟面之后axis equal，保证它是圆的。

请注意，您只需在顶部输入一次hold on，不需要在每个plot 命令之后。