C++动态显示或隐藏 FLTK 小部件？
我是 C++ 新手，以前从未使用过宏，但我相信它们可能允许我解决以下问题，尽管我欢迎其他解决方案。
我编写了以下宏：
#define COMMAND(NUMBER){ button_ ## NUMBER ## ->hide(); }
我想这样调用它
for (int i = 1; i < 10; i++)
{
COMMAND(i)
}
，希望当程序执行时它会执行相当于：
button_1->hide();
button_2->hide();
button_3->hide();
button_4->hide();
.
.
button_10->hide();
这个想法是我想根据配置动态地使 FLTK GUI 显示/隐藏小部件加载表单时读取的文件。
不幸的是，上面的宏似乎不起作用，它所做的是
button_i->hide();
导致编译错误，因为button_i不存在！
所以我的问题是：
A) 在 C++ 中可以做到这一点吗？
B) 宏能够完成这个任务吗？
C) 如果不能的话什么可以？
D）如果宏可以做到这一点，那么我该如何修改上面的代码才能真正让它工作！
谢谢
I'm new to C++ and never used macros before but I beleive they may allow me to solve the following problem although I would welcome alternative solutions.
I have written the following macro:
#define COMMAND(NUMBER){ button_ ## NUMBER ## ->hide(); }
and I want to call it like this
for (int i = 1; i < 10; i++)
{
COMMAND(i)
}
in the hope that when the program executes it would do the equivalent of:
button_1->hide();
button_2->hide();
button_3->hide();
button_4->hide();
.
.
button_10->hide();
The idea is that I want to make a FLTK GUI display/hide widgets dynamically depending on a configuration file being read in when the form is loaded.
Unfortunately it appears that the macro above doesn't work and instead what it does is
button_i->hide();
which causes a compile error because button_i doesn't exist!
So my questions are:
A) Is it possible to do this in C++?
B) Is a macro able to accomplish this?
C) If not what can?
D) If macros can do this then how do I amend the above code to actually get it to work!
Thanks
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评论（3）
我很确定有一种方法可以使宏技巧发挥作用，但还有更好的选择。
例如，您可以将按钮存储在数组中。
假设您的按钮有一个名为
struct button的类型，请像这样声明您的按钮：您需要像初始化各个 Button_X 变量一样初始化所有按钮。
然后您可以简单地执行以下操作：
或仅使用其编号切换任何单独的按钮。从长远来看，您可能会发现这比任何宏技巧都要好。
（警告：数组是基于
0的，因此您的第一个按钮是button[0]）I'm pretty sure there is a way to make a macro trick work, but there are better options.
You can, for example, store your buttons in an array.
Assuming your buttons have a type called
struct button, declare your buttons like this:You need to initialize all of them as you would have for your individual button_X variables.
Then you can simply do:
Or toggle any individual button with just its number. You'll probably find that better than any macro trick in the long run.
(Warning: arrays are
0-based, so your first button isbutton[0])如果您可以控制
button_2等变量，我建议您使用数组。这样你就可以使用如下所示的内容：当然，这对于放置在宏中来说是微不足道的。
一般来说，您无法使用 C 语言中的普通循环来完成您想要的任务。但是，如果您确实想要走这条路，请查看 boost 预处理器包。
If you have control over the
button_2etc. variables, I would recommend using an array instead. That way you could use a look like:Of course, this is trivial to place in a macro.
In general, you can't accomplish what you want with a plain loop in C. However, if you really want to go that route, look at the boost preprocessor package.
不要尝试自己管理按钮，FLTK 不喜欢这样。您将拥有一系列看不到的很棒的按钮。我不确定如何按照您想要的方式执行此操作，但我会这样做：
并让按钮成为 FLTK 窗口的子级。
Do not try to manage the buttons yourself, FLTK does not like that. You will have an awesome array of buttons that you cannot see. I am not sure how to do it the way you want but I would do it this way:
and let the buttons be children of the FLTK window.