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 #GtkTreeView
row or cell, you will have to do a little more work:
Set the #GtkWidget: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 #GtkWidget::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.Tooltip.setIcon. 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 #GtkWindow which
will be used as tooltip window. This works as follows:
Set #GtkWidget:has-tooltip and connect to #GtkWidget::query-tooltip as before.
Use gtk.widget.Widget.setTooltipWindow to set a #GtkWindow created by you as
tooltip window.
In the #GtkWidget::query-tooltip callback you can access your window using
gtk.widget.Widget.getTooltipWindow 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.
Basic tooltips can be realized simply by using gtk.widget.Widget.setTooltipText or gtk.widget.Widget.setTooltipMarkup 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 #GtkTreeView row or cell, you will have to do a little more work:
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 #GtkWindow which will be used as tooltip window. This works as follows: