GtkLayoutChild instances are created on demand once we have a widget, a
GtkLayoutManager, and a child widget. This makes testing their creation
fairly tricky.
Let's skip them, for the time being.
The GtkWidget::parent-set signal was removed in ff6cd8f7.
Instead of removing GtkLayoutChild instances associated to a widget
using notifications when the widget's parent changes, we can have
gtk_widget_unparent() call a method on GtkLayoutManager to remove any
eventual GtkLayoutChild instances associated to the widget.
When sending render nodes from the client to the daemon we add an id,
and whenever we're about to re-send the entire tree node we instead
send the old id. We track all the nodes for the previous frame
of the surface this way.
Having the id on the daemon side will allow us do to much better deltas.
We want to delay some rendering, and to make that safe we need to correctly
refcount the use of blob uris for the textures so that we don't unref
it while something is scheduled to use it.
- Rename GtkLegacyLayout to GtkCustomLayout
- Use for() to iterate over children in GtkBinLayout
- Whitespace fixes for code imported from GtkBox
- Store the GtkLayoutChild instances inside LayoutManager
- Simplify the GtkLayoutManager API by dropping unnecessary arguments
- Fix the ownership model of GtkLayoutManager
If a widget has a LayoutManager instance, then we want to parse layout
properties in UI description files; the grammar is similar to packing
properties in GtkContainer:
<child>
<object ...>
<property name="...">...</property>
<layout>
<property name="pname">value</property>
</layout>
</object>
</child>
The properties are applied after a child has been added to its parent,
to the parent's layout manager property should be set.
GtkLegacyLayout is a layout manager for the transitional period between
the introduction of layout managers and the removal of GtkWidget virtual
functions for the size negotiation.
Layout managers needs a way to store properties that control the layout
policy of a widget; typically, we used to store these in GtkContainer's
child properties, but since GtkLayoutManager is decoupled from the
actual container widget, we need a separate storage. Additionally, child
properties have their own downsides, like requiring a separate, global
GParamSpecPool storage, and additional lookup API.
GtkLayoutChild is a simple GObject class, which means you can introspect
and document it as you would any other type.
We can use a constructor property for existing container widgets with
a layout policy, and move the layout policy implementation out of the
widget itself and into a LayoutManager subclass.
We delegate the size request mode, the measuring, and the allocation of
a widget through a GtkLayoutManager instance, if one has been attached
to the widget; otherwise, we fall back to the widget's own implementation.
A base abstract class for layout manager delegate objects.
Layout managers are associated to a single widget, like event
controllers, and are responsible for measuring and allocating the
children of the widget they are bound to.
Otherwise we're getting warnings about allocating a widget we haven't
measured first, which is fair. The contents gizmo itself will later take
care about whether or not the real popover child is NULL.
