Basic tooltips can be realized simply by using Gtk.Widget.Set_Tooltip_Text or Gtk.Widget.Set_Tooltip_Markup without any explicit tooltip object.
When you need a tooltip with a little more fancy contents, like adding an image, or you want the tooltip to have different contents per Gtk.Tree_View.Gtk_Tree_View row or cell, you will have to do a little more work:
Set the Gtk.Widget.Gtk_Widget:has-tooltip property to True, this will
make GTK+ monitor the widget for motion and related events which are needed to determine when and where to show a tooltip.
Connect to the Gtk.Widget.Gtk_Widget::query-tooltip signal. This signal
will be emitted when a tooltip is supposed to be shown. One of the arguments passed to the signal handler is a GtkTooltip object. This is the object that we are about to display as a tooltip, and can be manipulated in your callback using functions like Gtk.Tooltip.Set_Icon. There are functions for setting the tooltip's markup, setting an image from a named icon, or even putting in a custom widget.
Return True from your query-tooltip handler. This causes the tooltip to be show. If you return False, it will not be shown.
In the probably rare case where you want to have even more control over the tooltip that is about to be shown, you can set your own Gtk.Window.Gtk_Window which will be used as tooltip window. This works as follows:
Set Gtk.Widget.Gtk_Widget:has-tooltip and connect to
Gtk.Widget.Gtk_Widget::query-tooltip as before. Use Gtk.Widget.Set_Tooltip_Window to set a Gtk.Window.Gtk_Window created by you as tooltip window.
In the Gtk.Widget.Gtk_Widget::query-tooltip callback you can access your
window using Gtk.Widget.Get_Tooltip_Window and manipulate as you wish. The semantics of the return value are exactly as before, return True to show the window, False to not show it.
function Get_Type return Glib.GType
type Gtk_Tooltip is access all Gtk_Tooltip_Record'Class;
type Gtk_Tooltip_Record is new GObject_Record with null record;
procedure Set_Custom
(Self : not null access Gtk_Tooltip_Record;
Custom_Widget : access Gtk.Widget.Gtk_Widget_Record'Class)
Replaces the widget packed into the tooltip with Custom_Widget. Custom_Widget does not get destroyed when the tooltip goes away. By default a box with a Gtk.Image.Gtk_Image and Gtk.Label.Gtk_Label is embedded in the tooltip, which can be configured using Gtk.Tooltip.Set_Markup and Gtk.Tooltip.Set_Icon. Since: gtk+ 2.12
a Gtk.Widget.Gtk_Widget, or null to unset the old custom widget.
procedure Set_Icon
(Self : not null access Gtk_Tooltip_Record;
Pixbuf : access Gdk.Pixbuf.Gdk_Pixbuf_Record'Class)
Sets the icon of the tooltip (which is in front of the text) to be Pixbuf. If Pixbuf is null, the image will be hidden. Since: gtk+ 2.12
a Gdk.Pixbuf.Gdk_Pixbuf, or null
procedure Set_Icon_From_Gicon
(Self : not null access Gtk_Tooltip_Record;
G_Icon : Glib.G_Icon.G_Icon;
Size : Gtk.Enums.Gtk_Icon_Size)
Sets the icon of the tooltip (which is in front of the text) to be the icon indicated by Gicon with the size indicated by Size. If Gicon is null, the image will be hidden. Since: gtk+ 2.20
a Glib.G_Icon.G_Icon representing the icon, or null
a stock icon size (Gtk.Enums.Gtk_Icon_Size)
procedure Set_Icon_From_Icon_Name
(Self : not null access Gtk_Tooltip_Record;
Icon_Name : UTF8_String := "";
Size : Gtk.Enums.Gtk_Icon_Size)
Sets the icon of the tooltip (which is in front of the text) to be the icon indicated by Icon_Name with the size indicated by Size. If Icon_Name is null, the image will be hidden. Since: gtk+ 2.14
an icon name, or null
a stock icon size (Gtk.Enums.Gtk_Icon_Size)
procedure Set_Icon_From_Stock
(Self : not null access Gtk_Tooltip_Record;
Stock_Id : UTF8_String := "";
Size : Gtk.Enums.Gtk_Icon_Size)
Sets the icon of the tooltip (which is in front of the text) to be the stock item indicated by Stock_Id with the size indicated by Size. If Stock_Id is null, the image will be hidden. Since: gtk+ 2.12 Deprecated since 3.10, 1
a stock id, or null
a stock icon size (Gtk.Enums.Gtk_Icon_Size)
procedure Set_Markup
(Self : not null access Gtk_Tooltip_Record;
Markup : UTF8_String := "")
Sets the text of the tooltip to be Markup, which is marked up with the [Pango text markup language][PangoMarkupFormat]. If Markup is null, the label will be hidden. Since: gtk+ 2.12
a markup string (see [Pango markup format][PangoMarkupFormat]) or null
procedure Set_Text
(Self : not null access Gtk_Tooltip_Record;
Text : UTF8_String := "")
Sets the text of the tooltip to be Text. If Text is null, the label will be hidden. See also Gtk.Tooltip.Set_Markup. Since: gtk+ 2.12
a text string or null
procedure Set_Tip_Area
(Self : not null access Gtk_Tooltip_Record;
Rect : Gdk.Rectangle.Gdk_Rectangle)
Sets the area of the widget, where the contents of this tooltip apply, to be Rect (in widget coordinates). This is especially useful for properly setting tooltips on Gtk.Tree_View.Gtk_Tree_View rows and cells, Gtk_Icon_Views, etc. For setting tooltips on Gtk.Tree_View.Gtk_Tree_View, please refer to the convenience functions for this: Gtk.Tree_View.Set_Tooltip_Row and Gtk.Tree_View.Set_Tooltip_Cell. Since: gtk+ 2.12
a Gdk.Rectangle.Gdk_Rectangle
procedure Trigger_Tooltip_Query
(Display : not null access Gdk.Display.Gdk_Display_Record'Class)
Triggers a new tooltip query on Display, in order to update the current visible tooltip, or to show/hide the current tooltip. This function is useful to call when, for example, the state of the widget changed by a key press. Since: gtk+ 2.12
a Gdk.Display.Gdk_Display