向 GtkButton 添加工具提示

Question

我想给 GtkButton 添加工具提示。
这似乎是一件容易的事，除了我不知道为什么不起作用。我有什么：
1)

GtkButton* button = gtk_button_new_with_label("button");   
gtk_widget_set_tooltip_text(button, "tooltip text");

2)

GtkButton* button = gtk_button_new_with_label("button"); 
GtkTooltips *button_bar_tips = gtk_tooltips_new();
gtk_tooltips_set_tip(GTK_TOOLTIPS (button_bar_tips), 
                     button , "tooltip text", NULL);

都试过

gtk_widget_set_has_tooltip(button, true);

但仍然没有运气。有任何想法吗？谢谢！

Answer 1

好吧，现在不推荐使用 GtkTooltips，所以让我们跳过选项 2)，至于选项 1)，它看起来完全适合我...

所以首先，确保你不要混合这两种方法，也许这是一个问题......

Answer 2

你混合了 GtkWidget 和 GtkButton：

GtkButton* button = gtk_button_ne*emphasized text*w_with_label("button");   
gtk_widget_set_tooltip_text(button, "tooltip text");

看到了吗？ gtk_widget_set_tooltip_text() 期望第一个参数是 GtkWidget，而不是 GtkButton，你的编译器（GCC？）应该抛出警告，像这样：

tooltips.c:23:3: warning: passing argument 1 of ‘gtk_widget_set_tooltip_text’ from incompatible pointer type [enabled by default]*emphasized text*
In file included from /usr/include/gtk-3.0/gtk/gtkapplication.h:27:0,
                 from /usr/include/gtk-3.0/gtk/gtkwindow.h:33,
                 from /usr/include/gtk-3.0/gtk/gtkdialog.h:33,
                 from /usr/include/gtk-3.0/gtk/gtkaboutdialog.h:30,
                 from /usr/include/gtk-3.0/gtk/gtk.h:31,
                 from tooltips.c:1:
/usr/include/gtk-3.0/gtk/gtkwidget.h:858:12: note: expected ‘struct GtkWidget *’ but argument is of type ‘struct GtkButton *’

下面是我的示例代码：

#include <gtk/gtk.h>
int main(int argc, char *argv[])
{
  GtkWidget *button, *window, *vbox;
  GtkButton *button2;

  gtk_init (&argc, &argv);

  window = gtk_window_new (GTK_WINDOW_TOPLEVEL);
  gtk_window_set_title (GTK_WINDOW (window), "Tool Tip Test");
  gtk_widget_set_size_request (window, 200, 200);
  gtk_container_set_border_width (GTK_CONTAINER (window), 5);
  g_signal_connect (G_OBJECT (window), "destroy",
      G_CALLBACK (gtk_main_quit), NULL);

  vbox = gtk_box_new (GTK_ORIENTATION_VERTICAL, 5);
  button = gtk_button_new_with_label ("Click me");
  gtk_widget_set_tooltip_text (button, "Tooltip of button");
  gtk_box_pack_start (GTK_BOX (vbox), button, TRUE, TRUE, 5);

  button2 = gtk_button_new_with_label ("No, click me");
  gtk_widget_set_tooltip_text (GTK_WIDGET (button2), "Tooltip of button2");
  gtk_box_pack_start (GTK_BOX (vbox), GTK_WIDGET (button2), TRUE, TRUE, 5);


  gtk_container_add (GTK_CONTAINER (window), vbox);

  gtk_widget_show_all (window);

  gtk_main ();
  return 0;
}

如果从以下位置删除 GTK_WIDGET()：

  gtk_widget_set_tooltip_text (GTK_WIDGET (button2), "Tooltip of button2");
  gtk_box_pack_start (GTK_BOX (vbox), GTK_WIDGET (button2), TRUE, TRUE, 5);

我的 GCC 会抛出这些警告。

因此，将 Gtk 中的所有小部件变量初始化为 GtkWidget 类型，然后在需要时将它们重新定义为其他类型，使用 GTK_BUTTON()、GTK_CONTAINER、GTK_BOX()、GTK_WINDOW() 是一个好方法...

Answer 3

我想既然没有指定GTK版本，GTK4的朋友可以在这里找一个GTK4的例子。

这里是一个使用gtk_widget_set_tooltip_text的GTK4示例。

将鼠标悬停在按钮上以查看工具提示。

/** tooltip.c   
 *
 * COMPILE
 *
 * gcc `pkg-config --cflags gtk4` -o tooltip tooltip.c `pkg-config --libs gtk4`
 *
 * RUN
 *
 * ./tooltip
 */

#include <gtk/gtk.h>

// Not strictly necessary, but here for maximum portability.
#if GLIB_CHECK_VERSION(2, 74, 0)
static int app_flags = G_APPLICATION_DEFAULT_FLAGS;
#else
static int app_flags = G_APPLICATION_FLAGS_NONE;
#endif

static void activate( GtkApplication *app, gpointer user_data )
{
    GtkWidget *window, *button;

    window = gtk_application_window_new( app );

    // You can add tooltip text to any GtkWidget. I used a GtkButton.
    // You could just as easily use a GtkLabel by itself, or a GtkBox.
    button = gtk_button_new_with_label( "hover here" );

    gtk_widget_set_tooltip_text( button, "hello world" );

    gtk_window_set_child( GTK_WINDOW( window ), button );

    gtk_widget_show(window);
}

int main (int argc, char **argv)
{
    GtkApplication *app;
    int status;

    puts("hover over the window to see the tooltip");

    app = gtk_application_new ("org.gtk.example", app_flags);
    g_signal_connect (app, "activate", G_CALLBACK (activate), NULL);
    status = g_application_run (G_APPLICATION (app), argc, argv);
    g_object_unref (app);

    return status;
}