diff --git a/docs/reference/gtk/gtk4-docs.xml b/docs/reference/gtk/gtk4-docs.xml
index 48d28d412c..3495ec1607 100644
--- a/docs/reference/gtk/gtk4-docs.xml
+++ b/docs/reference/gtk/gtk4-docs.xml
@@ -51,6 +51,7 @@
diff --git a/docs/reference/gtk/gtk4-sections.txt b/docs/reference/gtk/gtk4-sections.txt
index eda7e15c96..fdbcf599a3 100644
--- a/docs/reference/gtk/gtk4-sections.txt
+++ b/docs/reference/gtk/gtk4-sections.txt
@@ -1193,6 +1193,8 @@ gtk_filter_get_strictness
GtkFilterChange
gtk_filter_changed
+
+gtk_custom_filter_new
GTK_FILTER
GTK_IS_FILTER
@@ -1204,6 +1206,23 @@ GTK_FILTER_GET_CLASS
gtk_filter_get_type
+
+gtkcustomfilter
+GtkCustomFilter
+GtkCustomFilter
+GtkCustomFilterFunc
+gtk_custom_filter_new
+
+GTK_CUSTOM_FILTER
+GTK_IS_CUSTOM_FILTER
+GTK_TYPE_CUSTOM_FILTER
+GTK_CUSTOM_FILTER_CLASS
+GTK_IS_CUSTOM_FILTER_CLASS
+GTK_CUSTOM_FILTER_GET_CLASS
+
+gtk_custom_filter_get_type
+
+
gtkfilterlistmodel
GtkFilterListModel
diff --git a/docs/reference/gtk/gtk4.types.in b/docs/reference/gtk/gtk4.types.in
index df153a01e4..a8975f30bb 100644
--- a/docs/reference/gtk/gtk4.types.in
+++ b/docs/reference/gtk/gtk4.types.in
@@ -53,6 +53,7 @@ gtk_constraint_guide_get_type
gtk_constraint_layout_get_type
gtk_constraint_target_get_type
gtk_css_provider_get_type
+gtk_custom_filter_get_type
gtk_dialog_get_type
gtk_directory_list_get_type
gtk_drag_icon_get_type
diff --git a/gtk/gtk.h b/gtk/gtk.h
index 6953d0d3e5..60aaf1754c 100644
--- a/gtk/gtk.h
+++ b/gtk/gtk.h
@@ -116,6 +116,7 @@
#include
#include
#include
+#include
#include
#include
#include
diff --git a/gtk/gtkcustomfilter.c b/gtk/gtkcustomfilter.c
new file mode 100644
index 0000000000..d2ec8dc23a
--- /dev/null
+++ b/gtk/gtkcustomfilter.c
@@ -0,0 +1,157 @@
+/*
+ * Copyright © 2019 Benjamin Otte
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library. If not, see .
+ *
+ * Authors: Benjamin Otte
+ */
+
+#include "config.h"
+
+#include "gtkcustomfilter.h"
+
+#include "gtkintl.h"
+#include "gtktypebuiltins.h"
+
+/**
+ * SECTION:gtkcustomfilter
+ * @Title: GtkCustomFilter
+ * @Short_description: Filtering with callbacks
+ *
+ * #GtkCustomFilter is a #GtkFilter that uses a callback to determine whether
+ * to include an item or not.
+ */
+struct _GtkCustomFilter
+{
+ GtkFilter parent_instance;
+
+ GtkCustomFilterFunc match_func;
+ gpointer user_data;
+ GDestroyNotify user_destroy;
+};
+
+G_DEFINE_TYPE (GtkCustomFilter, gtk_custom_filter, GTK_TYPE_FILTER)
+
+static gboolean
+gtk_custom_filter_match (GtkFilter *filter,
+ gpointer item)
+{
+ GtkCustomFilter *self = GTK_CUSTOM_FILTER (filter);
+
+ if (!self->match_func)
+ return TRUE;
+
+ return self->match_func (item, self->user_data);
+}
+
+static GtkFilterMatch
+gtk_custom_filter_get_strictness (GtkFilter *filter)
+{
+ GtkCustomFilter *self = GTK_CUSTOM_FILTER (filter);
+
+ if (!self->match_func)
+ return GTK_FILTER_MATCH_ALL;
+
+ return GTK_FILTER_MATCH_SOME;
+}
+
+static void
+gtk_custom_filter_dispose (GObject *object)
+{
+ GtkCustomFilter *self = GTK_CUSTOM_FILTER (object);
+
+ if (self->user_destroy)
+ self->user_destroy (self->user_data);
+
+ G_OBJECT_CLASS (gtk_custom_filter_parent_class)->dispose (object);
+}
+
+static void
+gtk_custom_filter_class_init (GtkCustomFilterClass *class)
+{
+ GtkFilterClass *filter_class = GTK_FILTER_CLASS (class);
+ GObjectClass *object_class = G_OBJECT_CLASS (class);
+
+ filter_class->match = gtk_custom_filter_match;
+ filter_class->get_strictness = gtk_custom_filter_get_strictness;
+
+ object_class->dispose = gtk_custom_filter_dispose;
+}
+
+static void
+gtk_custom_filter_init (GtkCustomFilter *self)
+{
+}
+
+/**
+ * gtk_custom_filter_new:
+ * @match_func: (nullable): function to filter items
+ * @user_data: (nullable): user data to pass to @match_func
+ * @user_destroy: destory notify
+ *
+ * Creates a new filter using the given @match_func to filter
+ * items.
+ *
+ * If the filter func changes its filtering behavior,
+ * gtk_filter_changed() needs to be called.
+ *
+ * Returns: a new #GtkFilter
+ **/
+GtkFilter *
+gtk_custom_filter_new (GtkCustomFilterFunc match_func,
+ gpointer user_data,
+ GDestroyNotify user_destroy)
+{
+ GtkCustomFilter *result;
+
+ result = g_object_new (GTK_TYPE_CUSTOM_FILTER, NULL);
+
+ gtk_custom_filter_set_filter_func (result, match_func, user_data, user_destroy);
+
+ return GTK_FILTER (result);
+}
+
+/**
+ * gtk_custom_filter_set_filter_func:
+ * @self: a #GtkCustomFilter
+ * @match_func: (nullable): function to filter items
+ * @user_data: (nullable): user data to pass to @match_func
+ * @user_destroy: destory notify
+ *
+ * Sets (or unsets) the function used for filtering items.
+ *
+ * If the filter func changes its filtering behavior,
+ * gtk_filter_changed() needs to be called.
+ *
+ * If a previous function was set, its @user_destroy will be
+ * called now.
+ **/
+void
+gtk_custom_filter_set_filter_func (GtkCustomFilter *self,
+ GtkCustomFilterFunc match_func,
+ gpointer user_data,
+ GDestroyNotify user_destroy)
+{
+ g_return_if_fail (GTK_IS_CUSTOM_FILTER (self));
+ g_return_if_fail (match_func || (user_data == NULL && !user_destroy));
+
+ if (self->user_destroy)
+ self->user_destroy (self->user_data);
+
+ self->match_func = match_func;
+ self->user_data = user_data;
+ self->user_destroy = user_destroy;
+
+ gtk_filter_changed (GTK_FILTER (self), GTK_FILTER_CHANGE_DIFFERENT);
+}
diff --git a/gtk/gtkcustomfilter.h b/gtk/gtkcustomfilter.h
new file mode 100644
index 0000000000..c6ee063886
--- /dev/null
+++ b/gtk/gtkcustomfilter.h
@@ -0,0 +1,60 @@
+/*
+ * Copyright © 2019 Benjamin Otte
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library. If not, see .
+ *
+ * Authors: Benjamin Otte
+ */
+
+#ifndef __GTK_CUSTOM_FILTER_H__
+#define __GTK_CUSTOM_FILTER_H__
+
+#if !defined (__GTK_H_INSIDE__) && !defined (GTK_COMPILATION)
+#error "Only can be included directly."
+#endif
+
+#include
+
+G_BEGIN_DECLS
+
+/**
+ * GtkCustomFilterFunc:
+ * @item: (type GObject): The item to be matched
+ * @user_data: user data
+ *
+ * User function that is called to determine if the @item should be matched.
+ * If the filter matches the item, this function must return %TRUE. If the
+ * item should be filtered out, %FALSE must be returned.
+ *
+ * Returns: %TRUE to keep the item around
+ */
+typedef gboolean (* GtkCustomFilterFunc) (gpointer item, gpointer user_data);
+
+#define GTK_TYPE_CUSTOM_FILTER (gtk_custom_filter_get_type ())
+GDK_AVAILABLE_IN_ALL
+G_DECLARE_FINAL_TYPE (GtkCustomFilter, gtk_custom_filter, GTK, CUSTOM_FILTER, GtkFilter)
+GDK_AVAILABLE_IN_ALL
+GtkFilter * gtk_custom_filter_new (GtkCustomFilterFunc match_func,
+ gpointer user_data,
+ GDestroyNotify user_destroy);
+
+GDK_AVAILABLE_IN_ALL
+void gtk_custom_filter_set_filter_func (GtkCustomFilter *self,
+ GtkCustomFilterFunc match_func,
+ gpointer user_data,
+ GDestroyNotify user_destroy);
+
+G_END_DECLS
+
+#endif /* __GTK_CUSTOM_FILTER_H__ */
diff --git a/gtk/meson.build b/gtk/meson.build
index 91fb469abc..6103a77e3f 100644
--- a/gtk/meson.build
+++ b/gtk/meson.build
@@ -199,6 +199,7 @@ gtk_public_sources = files([
'gtkconstraintlayout.c',
'gtkconstraint.c',
'gtkcssprovider.c',
+ 'gtkcustomfilter.c',
'gtkcustomlayout.c',
'gtkdialog.c',
'gtkdirectorylist.c',
@@ -454,6 +455,7 @@ gtk_public_headers = files([
'gtkconstraintlayout.h',
'gtkconstraint.h',
'gtkcssprovider.h',
+ 'gtkcustomfilter.h',
'gtkcustomlayout.h',
'gtkdebug.h',
'gtkdialog.h',