Creates a binding between source_property on source and target_property
on target.
Whenever the source_property is changed the target_property is
updated using the same value. For instance:
g_object_bind_property (action, "active", widget, "sensitive", 0);
Will result in the "sensitive" property of the widget #GObject instance to be updated with the same value of the "active" property of the action #GObject instance.
If flags contains %G_BINDING_BIDIRECTIONAL then the binding will be mutual:
if target_property on target changes then the source_property on source
will be updated as well.
The binding will automatically be removed when either the source or the
target instances are finalized. To remove the binding without affecting the
source and the target you can just call g_object_unref() on the returned
#GBinding instance.
Removing the binding by calling g_object_unref() on it must only be done if
the binding, source and target are only used from a single thread and it
is clear that both source and target outlive the binding. Especially it
is not safe to rely on this if the binding, source or target can be
finalized from different threads. Keep another reference to the binding and
use g_binding_unbind() instead to be on the safe side.
A #GObject can have multiple bindings.
the property on source to bind
the target #GObject
the property on target to bind
flags to pass to #GBinding
Creates a binding between source_property on source and target_property
on target, allowing you to set the transformation functions to be used by
the binding.
This function is the language bindings friendly version of g_object_bind_property_full(), using #GClosures instead of function pointers.
the property on source to bind
the target #GObject
the property on target to bind
flags to pass to #GBinding
a #GClosure wrapping the transformation function from the source to the target, or %NULL to use the default
a #GClosure wrapping the transformation function from the target to the source, or %NULL to use the default
This function should almost never be called. It clears the filter
of any cached iterators that haven’t been reffed with
gtk_tree_model_ref_node(). This might be useful if the child model
being filtered is static (and doesn’t change often) and there has been
a lot of unreffed access to nodes. As a side effect of this function,
all unreffed iters will be invalid.
Converts child_path to a path relative to filter. That is, child_path
points to a path in the child model. The rerturned path will point to the
same row in the filtered model. If child_path isn’t a valid path on the
child model or points to a row which is not visible in filter, then %NULL
is returned.
Converts filter_path to a path on the child model of filter. That is,
filter_path points to a location in filter. The returned path will
point to the same location in the model not being filtered. If filter_path
does not point to a location in the child model, %NULL is returned.
Asks the GtkTreeDragSource to delete the row at path, because
it was moved somewhere else via drag-and-drop. Returns %FALSE
if the deletion fails because path no longer exists, or for
some model-specific reason. Should robustly handle a path no
longer found in the model!
Asks the GtkTreeDragSource to return a GdkContentProvider representing
the row at path. Should robustly handle a path no
longer found in the model!
This function is intended for #GObject implementations to re-enforce a [floating][floating-ref] object reference. Doing this is seldom required: all #GInitiallyUnowneds are created with a floating reference which usually just needs to be sunken by calling g_object_ref_sink().
Calls func on each node in model in a depth-first fashion.
If func returns %TRUE, then the tree ceases to be walked,
and gtk_tree_model_foreach() returns.
a function to be called on each row
Increases the freeze count on object. If the freeze count is
non-zero, the emission of "notify" signals on object is
stopped. The signals are queued until the freeze count is decreased
to zero. Duplicate notifications are squashed so that at most one
#GObject::notify signal is emitted for each property modified while the
object is frozen.
This is necessary for accessors that modify multiple properties to prevent premature notification while the object is still being modified.
Returns the type of the column.
the column index
Gets a named field from the objects table of associations (see g_object_set_data()).
name of the key for that association
Returns a set of flags supported by this interface.
The flags are a bitwise combination of GtkTreeModelFlags.
The flags supported should not change during the lifetime
of the tree_model.
Returns the number of columns supported by tree_model.
Gets a property of an object.
The value can be:
In general, a copy is made of the property contents and the caller is responsible for freeing the memory by calling g_value_unset().
Note that g_object_get_property() is really intended for language bindings, g_object_get() is much more convenient for C programming.
the name of the property to get
return location for the property value
This function gets back user data pointers stored via g_object_set_qdata().
A #GQuark, naming the user data pointer
Gets n_properties properties for an object.
Obtained properties will be set to values. All properties must be valid.
Warnings will be emitted and undefined behaviour may result if invalid
properties are passed in.
the names of each property to get
the values of each property to get
Checks whether object has a [floating][floating-ref] reference.
Sets iter to point to the first child of parent.
If parent has no children, %FALSE is returned and iter is
set to be invalid. parent will remain a valid node after this
function has been called.
If parent is %NULL returns the first node, equivalent to
gtk_tree_model_get_iter_first (tree_model, iter);
Sets iter to be the child of parent, using the given index.
The first index is 0. If n is too big, or parent has no children,
iter is set to an invalid iterator and %FALSE is returned. parent
will remain a valid node after this function has been called. As a
special case, if parent is %NULL, then the n-th root node
is set.
Sets iter to be the parent of child.
If child is at the toplevel, and doesn’t have a parent, then
iter is set to an invalid iterator and %FALSE is returned.
child will remain a valid node after this function has been
called.
iter will be initialized before the lookup is performed, so child
and iter cannot point to the same memory location.
Emits a "notify" signal for the property property_name on object.
When possible, eg. when signaling a property change from within the class that registered the property, you should use g_object_notify_by_pspec() instead.
Note that emission of the notify signal may be blocked with g_object_freeze_notify(). In this case, the signal emissions are queued and will be emitted (in reverse order) when g_object_thaw_notify() is called.
the name of a property installed on the class of object.
Emits a "notify" signal for the property specified by pspec on object.
This function omits the property name lookup, hence it is faster than g_object_notify().
One way to avoid using g_object_notify() from within the class that registered the properties, and using g_object_notify_by_pspec() instead, is to store the GParamSpec used with g_object_class_install_property() inside a static array, e.g.:
enum
{
PROP_0,
PROP_FOO,
PROP_LAST
};
static GParamSpec *properties[PROP_LAST];
static void
my_object_class_init (MyObjectClass *klass)
{
properties[PROP_FOO] = g_param_spec_int ("foo", "Foo", "The foo",
0, 100,
50,
G_PARAM_READWRITE);
g_object_class_install_property (gobject_class,
PROP_FOO,
properties[PROP_FOO]);
}
and then notify a change on the "foo" property with:
g_object_notify_by_pspec (self, properties[PROP_FOO]);
the #GParamSpec of a property installed on the class of object.
Lets the tree ref the node.
This is an optional method for models to implement. To be more specific, models may ignore this call as it exists primarily for performance reasons.
This function is primarily meant as a way for views to let caching models know when nodes are being displayed (and hence, whether or not to cache that node). Being displayed means a node is in an expanded branch, regardless of whether the node is currently visible in the viewport. For example, a file-system based model would not want to keep the entire file-hierarchy in memory, just the sections that are currently being displayed by every current view.
A model should be expected to be able to get an iter independent of its reffed state.
Increase the reference count of object, and possibly remove the
[floating][floating-ref] reference, if object has a floating reference.
In other words, if the object is floating, then this call "assumes ownership" of the floating reference, converting it to a normal reference by clearing the floating flag while leaving the reference count unchanged. If the object is not floating, then this call adds a new normal reference increasing the reference count by one.
Since GLib 2.56, the type of object will be propagated to the return type
under the same conditions as for g_object_ref().
Emits ::row_changed for each row in the child model, which causes the filter to re-evaluate whether a row is visible or not.
Emits the ::row-deleted signal on tree_model.
See [signalGtk.TreeModel::row-deleted].
This should be called by models after a row has been removed.
The location pointed to by path should be the location that
the row previously was at. It may not be a valid location anymore.
Nodes that are deleted are not unreffed, this means that any outstanding references on the deleted node should not be released.
Emits the ::row-has-child-toggled signal on tree_model.
See [signalGtk.TreeModel::row-has-child-toggled].
This should be called by models after the child state of a node changes.
a GtkTreePath pointing to the changed row
a valid GtkTreeIter pointing to the changed row
Emits the ::rows-reordered signal on tree_model.
See [signalGtk.TreeModel::rows-reordered].
This should be called by models when their rows have been reordered.
a GtkTreePath pointing to the tree node whose children have been reordered
a valid GtkTreeIter pointing to the node whose children have been reordered, or %NULL if the depth of path is 0
an array of integers mapping the current position of each child to its old position before the re-ordering, i.e. new_order``[newpos] = oldpos
Releases all references to other objects. This can be used to break reference cycles.
This function should only be called from object system implementations.
Each object carries around a table of associations from strings to pointers. This function lets you set an association.
If the object already had an association with that name, the old association will be destroyed.
Internally, the key is converted to a #GQuark using g_quark_from_string().
This means a copy of key is kept permanently (even after object has been
finalized) — so it is recommended to only use a small, bounded set of values
for key in your program, to avoid the #GQuark storage growing unbounded.
name of the key
data to associate with that key
With the n_columns and types parameters, you give an array of column
types for this model (which will be exposed to the parent model/view).
The func, data and destroy parameters are for specifying the modify
function. The modify function will get called for each
data access, the goal of the modify function is to return the data which
should be displayed at the location specified using the parameters of the
modify function.
Note that gtk_tree_model_filter_set_modify_func() can only be called once for a given filter model.
The GTypes of the columns.
A GtkTreeModelFilterModifyFunc
Sets a property on an object.
the name of the property to set
the value
Sets column of the child_model to be the column where filter should
look for visibility information. columns should be a column of type
%G_TYPE_BOOLEAN, where %TRUE means that a row is visible, and %FALSE
if not.
Note that gtk_tree_model_filter_set_visible_func() or gtk_tree_model_filter_set_visible_column() can only be called once for a given filter model.
A int which is the column containing the visible information
Sets the visible function used when filtering the filter to be func.
The function should return %TRUE if the given row should be visible and
%FALSE otherwise.
If the condition calculated by the function changes over time (e.g. because it depends on some global parameters), you must call gtk_tree_model_filter_refilter() to keep the visibility information of the model up-to-date.
Note that func is called whenever a row is inserted, when it may still
be empty. The visible function should therefore take special care of empty
rows, like in the example below.
static gboolean
visible_func (GtkTreeModel *model,
GtkTreeIter *iter,
gpointer data)
{
// Visible if row is non-empty and first column is “HI”
char *str;
gboolean visible = FALSE;
gtk_tree_model_get (model, iter, 0, &str, -1);
if (str && strcmp (str, "HI") == 0)
visible = TRUE;
g_free (str);
return visible;
}
Note that gtk_tree_model_filter_set_visible_func() or gtk_tree_model_filter_set_visible_column() can only be called once for a given filter model.
A GtkTreeModelFilterVisibleFunc, the visible function
Remove a specified datum from the object's data associations, without invoking the association's destroy handler.
name of the key
This function gets back user data pointers stored via
g_object_set_qdata() and removes the data from object
without invoking its destroy() function (if any was
set).
Usually, calling this function is only required to update
user data pointers with a destroy notifier, for example:
void
object_add_to_user_list (GObject *object,
const gchar *new_string)
{
// the quark, naming the object data
GQuark quark_string_list = g_quark_from_static_string ("my-string-list");
// retrieve the old string list
GList *list = g_object_steal_qdata (object, quark_string_list);
// prepend new string
list = g_list_prepend (list, g_strdup (new_string));
// this changed 'list', so we need to set it again
g_object_set_qdata_full (object, quark_string_list, list, free_string_list);
}
static void
free_string_list (gpointer data)
{
GList *node, *list = data;
for (node = list; node; node = node->next)
g_free (node->data);
g_list_free (list);
}
Using g_object_get_qdata() in the above example, instead of g_object_steal_qdata() would have left the destroy function set, and thus the partial string list would have been freed upon g_object_set_qdata_full().
A #GQuark, naming the user data pointer
Reverts the effect of a previous call to
g_object_freeze_notify(). The freeze count is decreased on object
and when it reaches zero, queued "notify" signals are emitted.
Duplicate notifications for each property are squashed so that at most one #GObject::notify signal is emitted for each property, in the reverse order in which they have been queued.
It is an error to call this function when the freeze count is zero.
Decreases the reference count of object. When its reference count
drops to 0, the object is finalized (i.e. its memory is freed).
If the pointer to the #GObject may be reused in future (for example, if it is an instance variable of another object), it is recommended to clear the pointer to %NULL rather than retain a dangling pointer to a potentially invalid #GObject instance. Use g_clear_object() for this.
Lets the tree unref the node.
This is an optional method for models to implement. To be more specific, models may ignore this call as it exists primarily for performance reasons. For more information on what this means, see gtk_tree_model_ref_node().
Please note that nodes that are deleted are not unreffed.
This function essentially limits the life time of the closure to
the life time of the object. That is, when the object is finalized,
the closure is invalidated by calling g_closure_invalidate() on
it, in order to prevent invocations of the closure with a finalized
(nonexisting) object. Also, g_object_ref() and g_object_unref() are
added as marshal guards to the closure, to ensure that an extra
reference count is held on object during invocation of the
closure. Usually, this function will be called on closures that
use this object as closure data.
#GClosure to watch
Find the #GParamSpec with the given name for an
interface. Generally, the interface vtable passed in as g_iface
will be the default vtable from g_type_default_interface_ref(), or,
if you know the interface has already been loaded,
g_type_default_interface_peek().
any interface vtable for the interface, or the default vtable for the interface
name of a property to look up.
Add a property to an interface; this is only useful for interfaces that are added to GObject-derived types. Adding a property to an interface forces all objects classes with that interface to have a compatible property. The compatible property could be a newly created #GParamSpec, but normally g_object_class_override_property() will be used so that the object class only needs to provide an implementation and inherits the property description, default value, bounds, and so forth from the interface property.
This function is meant to be called from the interface's default
vtable initialization function (the class_init member of
#GTypeInfo.) It must not be called after after class_init has
been called for any object types implementing this interface.
If pspec is a floating reference, it will be consumed.
any interface vtable for the interface, or the default vtable for the interface.
the #GParamSpec for the new property
Lists the properties of an interface.Generally, the interface
vtable passed in as g_iface will be the default vtable from
g_type_default_interface_ref(), or, if you know the interface has
already been loaded, g_type_default_interface_peek().
any interface vtable for the interface, or the default vtable for the interface
Creates a new instance of a #GObject subtype and sets its properties.
Construction parameters (see %G_PARAM_CONSTRUCT, %G_PARAM_CONSTRUCT_ONLY) which are not explicitly specified are set to their default values.
the type id of the #GObject subtype to instantiate
an array of #GParameter
A
GtkTreeModelwhich hides parts of an underlying tree modelA
GtkTreeModelFilteris a tree model which wraps another tree model, and can do the following things:Filter specific rows, based on data from a “visible column”, a column storing booleans indicating whether the row should be filtered or not, or based on the return value of a “visible function”, which gets a model, iter and user_data and returns a boolean indicating whether the row should be filtered or not.
Modify the “appearance” of the model, using a modify function. This is extremely powerful and allows for just changing some values and also for creating a completely different model based on the given child model.
Set a different root node, also known as a “virtual root”. You can pass in a
GtkTreePathindicating the root node for the filter at construction time.The basic API is similar to
GtkTreeModelSort. For an example on its usage, see the section onGtkTreeModelSort.When using
GtkTreeModelFilter, it is important to realize thatGtkTreeModelFiltermaintains an internal cache of all nodes which are visible in its clients. The cache is likely to be a subtree of the tree exposed by the child model.GtkTreeModelFilterwill not cache the entire child model when unnecessary to not compromise the caching mechanism that is exposed by the reference counting scheme. If the child model implements reference counting, unnecessary signals may not be emitted because of reference counting rule 3, see theGtkTreeModeldocumentation. (Note that e.g.GtkTreeStoredoes not implement reference counting and will always emit all signals, even when the receiving node is not visible).Because of this, limitations for possible visible functions do apply. In general, visible functions should only use data or properties from the node for which the visibility state must be determined, its siblings or its parents. Usually, having a dependency on the state of any child node is not possible, unless references are taken on these explicitly. When no such reference exists, no signals may be received for these child nodes (see reference counting rule number 3 in the
GtkTreeModelsection).Determining the visibility state of a given node based on the state of its child nodes is a frequently occurring use case. Therefore,
GtkTreeModelFilterexplicitly supports this. For example, when a node does not have any children, you might not want the node to be visible. As soon as the first row is added to the node’s child level (or the last row removed), the node’s visibility should be updated.This introduces a dependency from the node on its child nodes. In order to accommodate this,
GtkTreeModelFiltermust make sure the necessary signals are received from the child model. This is achieved by building, for all nodes which are exposed as visible nodes toGtkTreeModelFilter's clients, the child level (if any) and take a reference on the first node in this level. Furthermore, for every row-inserted, row-changed or row-deleted signal (also these which were not handled because the node was not cached),GtkTreeModelFilterwill check if the visibility state of any parent node has changed.Beware, however, that this explicit support is limited to these two cases. For example, if you want a node to be visible only if two nodes in a child’s child level (2 levels deeper) are visible, you are on your own. In this case, either rely on
GtkTreeStoreto emit all signals because it does not implement reference counting, or for models that do implement reference counting, obtain references on these child levels yourself.