http://mail.gnome.org/archives/gtk-app-devel-list/2003-April/msg00204.html

Page numbers in GtkNotebook

• From: Manu C S
• To: gtk-app-devel-list gnome org
• Subject: Page numbers in GtkNotebook
• Date: Tue, 15 Apr 2003 12:50:21 -0500 (CDT)

Hi,How does one find out the page numbers of tabs in GtkNotebook?I tried gtk_notebook_get_current_page() in a callback forswitch page signal, but the page number I get from this varies

each time.

I want to be able to do something like this in my code:

-------------------------------------------------------------

#define PAGE_0  0

#define PAGE_1  1

#define PAGE_2  2

...

on_top_switch_page (GtkNotebook* notebook, ....)

{

curr_page = gtk_notebook_get_current_page(notebook);

switch (curr_page) {

case PAGE_0:

break;

case PAGE_1:

break;

....

}

}

-------------------------------------------------------------

I found this question asked in the archives (2000-Jul), but

I couldn't locate any suitable answers.

Can anyone please help? It's rather urgent.

Thanks,

Manu

Re: Page numbers in GtkNotebook

• From: “Audrey Vernon”
• To: “Manu C S” ,
• Subject: Re: Page numbers in GtkNotebook
• Date: Tue, 15 Apr 2003 23:34:55 -0600

Dear Audrey,>Then you can get the notebook label or the widget name or something else to>uniquely identify which tab is actually open.>

>I'm not sure if this is ideal, but it worked for me.

It works for me too!

Also, while working on your solution I found that

if I use

g_signal_connect_after(...switch_page...)

instead of

g_signal_connect(...switch_page...)

then in the callback for switch_page I can do:

on_nb1_main_options_switch_page (GtkNotebook     *notebook,

GtkNotebookPage *page,

guint            page_num,

gpointer         user_data)

{

switch (page_num) {

case 0:

break;

case 1:

break;

...

}

}

where page_num is the correct ascending ordered page

number I want!

For example, if my notebook looks like this:

+---+---+---+---+--------------------------

| A | B | C | D | ....

+---+---+---+---+--------------------------

then page_num will be 0 for A, 1 for B, 2 for C and so on...!

Thank you so much.

Regards,

Manu

收到destroy信号后，GtkWidget会被销毁，但是gtk_main()循环还在继续，还需要调用gtk_main_quit()来结束循环。
destroy信号可以连接自定义的回调函数处理别的事情，但是不管怎么样，收到destroy信号以后，widget都会被销毁。
举个例子：
#include

void destroy(GtkObject *window, gpointer user_data)
{
g_print(“OH no no ~\n”);
}

对于gtk中不同信号，对应的回调函数原型是不同的。举例说明如何找到相应信号的回调函数原型：

g_signal_connect_object(buffer, “mark_set”, G_CALLBACK(on_mark_set), statusbar, 0);

首先，mark_set是属于GtkTextBuffer的一个信号(BTW,GtkTextBuffer正是上述函数第一个参数的数据类型)；
在GTK＋ Reference Manual 中找到GtkTextBuffer这一项，
点击signals，可以看到属于这个类型的所有信号，
点击mark_set，就可以得到这个信号的回调函数原型。

gtk编程中常用到这两个函数，但是很多人对这两个函数的区别却不太清楚，至少是解释得不够准确。

我在这里找到了确却的解释：
http://gtkforums.com/viewtopic.php?t=1177

简单的说，swapped函数会交换回调函数参数的顺序。

这有什么好处？从例子上看：

<br /> /*这个函数会删除button，尽管用户数据的值是other_widget*/<br /> /* this will delete 'button' on its clicked signal, even though we're passing 'other_widget' as user_data */<br /> g_signal_connect(G_OBJECT(button), "clicked", G_CALLBACK(gtk_widget_destroy), (gpointer)other_widget);<br /> /*这个函数会删除other_widget*/<br /> /* this will delete 'other_widget' on button's clicked signal */<br /> g_signal_connect_swapped(G_OBJECT(button), "clicked", G_CALLBACK(gtk_widget_destroy), (gpointer)other_widget);<br />

应该是这样的：

char *strcat(char *s, char *t)

把*t连接到*s,并保存在*s中，*s没有足够空间的话，编译器找不到这个小虫子，gdb也没有发现它，一运行它就钻出来…

一个可行的方案：

#include <stdio.h>
#include <string.h>

#define MAX_NUM 100

int main()
{
char fn[MAX_NUM];
char *s = “abc”;
char *t = “def”;

strcpy(fn, s);
strcat(fn, t);

printf(“%s\n”, fn);

return 0;
}

另一个似乎也不错：
#include <stdio.h>

#define MAX_NUM 100

int main()
{
char fn[MAX_NUM];
char *s = “abc”;
char *t = “def”;

sprintf(fn, “%s%s”, s, t);