Add a color picker implementation for gnome-shel

This adds a GtkColorPicker implementation that talks
to gnome-shell to get a color.

gtk/gtkcoloreditor.c

@@ -24,7 +24,9 @@
 #include "gtkcolorscaleprivate.h"
 #include "gtkcolorswatchprivate.h"
 #include "gtkcolorutils.h"
+#include "gtkcolorpickerprivate.h"
 #include "gtkgrid.h"
+#include "gtkbutton.h"
 #include "gtkintl.h"
 #include "gtkorientable.h"
 #include "gtkentry.h"
@@ -61,6 +63,9 @@ struct _GtkColorEditorPrivate
   GtkAdjustment *v_adj;
   GtkAdjustment *a_adj;
 
+  GtkWidget *picker_button;
+  GtkColorPicker *picker;
+
   gint popup_position;
 
   guint text_changed : 1;
@@ -337,6 +342,36 @@ scaled_adjustment (GtkAdjustment *a,
   return as;
 }
 
+static void
+color_picked (GObject      *source,
+              GAsyncResult *res,
+              gpointer      data)
+{
+  GtkColorPicker *picker = GTK_COLOR_PICKER (source);
+  GtkColorEditor *editor = data;
+  GError *error = NULL;
+  GdkRGBA *color;
+
+  color = gtk_color_picker_pick_finish (picker, res, &error);
+  if (color == NULL)
+    {
+      g_warning ("Picking color failed: %s", error->message);
+      g_error_free (error);
+    }
+  else
+    {
+      gtk_color_chooser_set_rgba (GTK_COLOR_CHOOSER (editor), color);
+      gdk_rgba_free (color);
+    }
+}
+
+static void
+pick_color (GtkButton      *button,
+            GtkColorEditor *editor)
+{
+  gtk_color_picker_pick (editor->priv->picker, color_picked, editor);
+}
+
 static void
 gtk_color_editor_init (GtkColorEditor *editor)
 {
@@ -385,6 +420,10 @@ gtk_color_editor_init (GtkColorEditor *editor)
   gtk_widget_add_controller (editor->priv->a_entry, controller);
 
   gtk_style_context_remove_class (gtk_widget_get_style_context (editor->priv->swatch), "activatable");
+
+  editor->priv->picker = gtk_color_picker_new ();
+  if (editor->priv->picker == NULL)
+    gtk_widget_hide (editor->priv->picker_button);
 }
 
 static void
@@ -393,6 +432,7 @@ gtk_color_editor_dispose (GObject *object)
   GtkColorEditor *editor = GTK_COLOR_EDITOR (object);
 
   dismiss_current_popup (editor);
+  g_clear_object (&editor->priv->picker);
 
   G_OBJECT_CLASS (gtk_color_editor_parent_class)->dispose (object);
 }
@@ -495,6 +535,7 @@ gtk_color_editor_class_init (GtkColorEditorClass *class)
   gtk_widget_class_bind_template_child_private (widget_class, GtkColorEditor, s_adj);
   gtk_widget_class_bind_template_child_private (widget_class, GtkColorEditor, v_adj);
   gtk_widget_class_bind_template_child_private (widget_class, GtkColorEditor, a_adj);
+  gtk_widget_class_bind_template_child_private (widget_class, GtkColorEditor, picker_button);
 
   gtk_widget_class_bind_template_callback (widget_class, hsv_changed);
   gtk_widget_class_bind_template_callback (widget_class, dismiss_current_popup);
@@ -503,6 +544,7 @@ gtk_color_editor_class_init (GtkColorEditorClass *class)
   gtk_widget_class_bind_template_callback (widget_class, entry_apply);
   gtk_widget_class_bind_template_callback (widget_class, entry_focus_changed);
   gtk_widget_class_bind_template_callback (widget_class, popup_edit);
+  gtk_widget_class_bind_template_callback (widget_class, pick_color);
 }
 
 static void

gtk/gtkcolorpicker.c

@@ -0,0 +1,59 @@
+/* GTK - The GIMP Toolkit
+ * Copyright (C) 2018, Red Hat, Inc
+ *
+ * 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 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 <http://www.gnu.org/licenses/>.
+ */
+
+#include "config.h"
+
+#include "gtkcolorpickerprivate.h"
+#include "gtkcolorpickerportalprivate.h"
+#include "gtkcolorpickershellprivate.h"
+#include "gtkprivate.h"
+#include <gio/gio.h>
+
+
+G_DEFINE_INTERFACE_WITH_CODE (GtkColorPicker, gtk_color_picker, G_TYPE_OBJECT,
+                              g_type_interface_add_prerequisite (g_define_type_id, G_TYPE_INITABLE);)
+
+static void
+gtk_color_picker_default_init (GtkColorPickerInterface *iface)
+{
+}
+
+void
+gtk_color_picker_pick (GtkColorPicker      *picker,
+                       GAsyncReadyCallback  callback,
+                       gpointer             user_data)
+{
+  GTK_COLOR_PICKER_GET_INTERFACE (picker)->pick (picker, callback, user_data);
+}
+
+GdkRGBA *
+gtk_color_picker_pick_finish (GtkColorPicker  *picker,
+                              GAsyncResult    *res,
+                              GError         **error)
+{
+  return GTK_COLOR_PICKER_GET_INTERFACE (picker)->pick_finish (picker, res, error);
+}
+
+GtkColorPicker *
+gtk_color_picker_new (void)
+{
+  if (gtk_should_use_portal ())
+    return gtk_color_picker_portal_new ();
+  else
+    return gtk_color_picker_shell_new ();
+}
+

gtk/gtkcolorpickerportal.c

@@ -0,0 +1,239 @@
+/* GTK - The GIMP Toolkit
+ * Copyright (C) 2018, Red Hat, Inc
+ *
+ * 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 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 <http://www.gnu.org/licenses/>.
+ */
+
+#include "config.h"
+
+#include "gtkcolorpickerportalprivate.h"
+#include <gio/gio.h>
+
+struct _GtkColorPickerPortal
+{
+  GObject parent_instance;
+
+  GDBusProxy *portal_proxy;
+  guint portal_signal_id;
+  GTask *task;
+};
+
+struct _GtkColorPickerPortalClass
+{
+  GObjectClass parent_class;
+};
+
+static GInitableIface *initable_parent_iface;
+static void gtk_color_picker_portal_initable_iface_init (GInitableIface *iface);
+static void gtk_color_picker_portal_iface_init (GtkColorPickerInterface *iface);
+
+G_DEFINE_TYPE_WITH_CODE (GtkColorPickerPortal, gtk_color_picker_portal, G_TYPE_OBJECT,
+                         G_IMPLEMENT_INTERFACE (G_TYPE_INITABLE, gtk_color_picker_portal_initable_iface_init)
+                         G_IMPLEMENT_INTERFACE (GTK_TYPE_COLOR_PICKER, gtk_color_picker_portal_iface_init))
+
+static gboolean
+gtk_color_picker_portal_initable_init (GInitable     *initable,
+                                       GCancellable  *cancellable,
+                                       GError       **error)
+{
+  GtkColorPickerPortal *picker = GTK_COLOR_PICKER_PORTAL (initable);
+  char *owner;
+  GVariant *ret;
+  guint version;
+
+  picker->portal_proxy = g_dbus_proxy_new_for_bus_sync (G_BUS_TYPE_SESSION,
+                                                        G_DBUS_PROXY_FLAGS_NONE,
+                                                        NULL,
+                                                        "org.freedesktop.portal.Desktop",
+                                                        "/org/freedesktop/portal/desktop",
+                                                        "org.freedesktop.portal.Screenshot",
+                                                        NULL,
+                                                        error);
+
+  if (picker->portal_proxy == NULL)
+    {
+      g_warning ("No screenshot portal: %s", (*error)->message);
+      return FALSE;
+    }
+
+ owner = g_dbus_proxy_get_name_owner (picker->portal_proxy);
+  if (owner == NULL)
+    {
+      g_warning ("No screenshot portal");
+      g_clear_object (&picker->portal_proxy);
+      return FALSE;
+    }
+  g_free (owner);
+
+  ret = g_dbus_proxy_get_cached_property (picker->portal_proxy, "version");
+  g_variant_get (ret, "u", &version);
+  g_variant_unref (ret);
+  if (version != 2)
+    {
+      g_warning ("Screenshot portal version: %u", version);
+      g_clear_object (&picker->portal_proxy);
+      return FALSE;
+    }
+
+  return TRUE;
+}
+
+static void
+gtk_color_picker_portal_initable_iface_init (GInitableIface *iface)
+{
+  initable_parent_iface = g_type_interface_peek_parent (iface);
+  iface->init = gtk_color_picker_portal_initable_init;
+}
+
+static void
+gtk_color_picker_portal_init (GtkColorPickerPortal *picker)
+{
+}
+
+static void
+gtk_color_picker_portal_finalize (GObject *object)
+{
+  GtkColorPickerPortal *picker = GTK_COLOR_PICKER_PORTAL (object);
+
+  g_clear_object (&picker->portal_proxy);
+
+  G_OBJECT_CLASS (gtk_color_picker_portal_parent_class)->finalize (object);
+}
+
+static void
+gtk_color_picker_portal_class_init (GtkColorPickerPortalClass *class)
+{
+  GObjectClass *object_class = G_OBJECT_CLASS (class);
+
+  object_class->finalize = gtk_color_picker_portal_finalize;
+}
+
+GtkColorPicker *
+gtk_color_picker_portal_new (void)
+{
+  return GTK_COLOR_PICKER (g_initable_new (GTK_TYPE_COLOR_PICKER_PORTAL, NULL, NULL, NULL));
+}
+
+static void
+portal_response_received (GDBusConnection *connection,
+                          const char      *sender_name,
+                          const char      *object_path,
+                          const char      *interface_name,
+                          const char      *signal_name,
+                          GVariant        *parameters,
+                          gpointer         user_data)
+{
+  GtkColorPickerPortal *picker = user_data;
+  guint32 response;
+  GVariant *ret;
+
+  g_dbus_connection_signal_unsubscribe (connection, picker->portal_signal_id);
+  picker->portal_signal_id = 0;
+
+  g_variant_get (parameters, "(u@a{sv})", &response, &ret);
+
+  if (response == 0)
+    {
+      GdkRGBA c;
+
+      c.alpha = 1.0;
+      if (g_variant_lookup (ret, "color", "(ddd)", &c.red, &c.green, &c.blue))
+        g_task_return_pointer (picker->task, gdk_rgba_copy (&c), (GDestroyNotify)gdk_rgba_free);
+      else
+        g_task_return_new_error (picker->task,
+                                 G_IO_ERROR,
+                                 G_IO_ERROR_FAILED,
+                                 "No color received");
+    }
+  else
+    g_task_return_new_error (picker->task,
+                             G_IO_ERROR,
+                             G_IO_ERROR_FAILED,
+                             "PickColor error");
+
+  g_variant_unref (ret);
+
+  g_clear_object (&picker->task);
+}
+
+static void
+gtk_color_picker_portal_pick (GtkColorPicker      *cp,
+                              GAsyncReadyCallback  callback,
+                              gpointer             user_data)
+{
+  GtkColorPickerPortal *picker = GTK_COLOR_PICKER_PORTAL (cp);
+  GVariantBuilder options;
+  char *token;
+  GDBusConnection *connection;
+  char *sender;
+  char *handle;
+  int i;
+
+  if (picker->task)
+    return;
+
+  picker->task = g_task_new (picker, NULL, callback, user_data);
+
+  connection = g_dbus_proxy_get_connection (picker->portal_proxy);
+
+  token = g_strdup_printf ("gtk%d", g_random_int_range (0, G_MAXINT));
+  sender = g_strdup (g_dbus_connection_get_unique_name (connection) + 1);
+  for (i = 0; sender[i]; i++)
+    if (sender[i] == '.')
+      sender[i] = '_';
+
+  handle = g_strdup_printf ("/org/freedesktop/portal/desktop/request/%s/%s", sender, token);
+  picker->portal_signal_id = g_dbus_connection_signal_subscribe (connection,
+                                                                 "org.freedesktop.portal.Desktop",
+                                                                 "org.freedesktop.portal.Request",
+                                                                 "Response",
+                                                                 handle,
+                                                                 NULL,
+                                                                 G_DBUS_SIGNAL_FLAGS_NO_MATCH_RULE,
+                                                                 portal_response_received,
+                                                                 picker,
+                                                                 NULL);
+
+  g_free (handle);
+
+  g_variant_builder_init (&options, G_VARIANT_TYPE_VARDICT);
+  g_variant_builder_add (&options, "{sv}", "handle_token", g_variant_new_string (token));
+  g_free (token);
+
+  g_dbus_proxy_call (picker->portal_proxy,
+                     "PickColor",
+                     g_variant_new ("(sa{sv})", "", &options),
+                     0,
+                     -1,
+                     NULL,
+                     NULL,
+                     NULL);
+}
+
+static GdkRGBA *
+gtk_color_picker_portal_pick_finish (GtkColorPicker  *cp,
+                                     GAsyncResult    *res,
+                                     GError         **error)
+{
+  g_return_val_if_fail (g_task_is_valid (res, cp), NULL);
+
+  return g_task_propagate_pointer (G_TASK (res), error);
+}
+
+static void
+gtk_color_picker_portal_iface_init (GtkColorPickerInterface *iface)
+{
+  iface->pick = gtk_color_picker_portal_pick;
+  iface->pick_finish = gtk_color_picker_portal_pick_finish;
+}

gtk/gtkcolorpickerportalprivate.h

@@ -0,0 +1,41 @@
+/*
+ * GTK - The GIMP Toolkit
+ * Copyright (C) 2018 Red Hat, Inc.
+ * All rights reserved.
+ *
+ * This Library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Library General Public License as
+ * published by the Free Software Foundation; either version 2 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
+ * Library General Public License for more details.
+ *
+ * You should have received a copy of the GNU Library General Public
+ * License along with this library. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef __GTK_COLOR_PICKER_PORTAL_H__
+#define __GTK_COLOR_PICKER_PORTAL_H__
+
+
+#if !defined (__GTK_H_INSIDE__) && !defined (GTK_COMPILATION)
+#error "Only <gtk/gtk.h> can be included directly."
+#endif
+
+#include <gtk/gtkcolorpickerprivate.h>
+
+G_BEGIN_DECLS
+
+
+#define GTK_TYPE_COLOR_PICKER_PORTAL gtk_color_picker_portal_get_type ()
+G_DECLARE_FINAL_TYPE (GtkColorPickerPortal, gtk_color_picker_portal, GTK, COLOR_PICKER_PORTAL, GObject)
+
+GDK_AVAILABLE_IN_ALL
+GtkColorPicker * gtk_color_picker_portal_new (void);
+
+G_END_DECLS
+
+#endif  /* __GTK_COLOR_PICKER_PORTAL_H__ */

gtk/gtkcolorpickerprivate.h

@@ -0,0 +1,69 @@
+/*
+ * GTK - The GIMP Toolkit
+ * Copyright (C) 2018 Red Hat, Inc.
+ * All rights reserved.
+ *
+ * This Library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Library General Public License as
+ * published by the Free Software Foundation; either version 2 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
+ * Library General Public License for more details.
+ *
+ * You should have received a copy of the GNU Library General Public
+ * License along with this library. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef __GTK_COLOR_PICKER_H__
+#define __GTK_COLOR_PICKER_H__
+
+
+#if !defined (__GTK_H_INSIDE__) && !defined (GTK_COMPILATION)
+#error "Only <gtk/gtk.h> can be included directly."
+#endif
+
+#include <gtk/gtkwindow.h>
+
+G_BEGIN_DECLS
+
+
+#define GTK_TYPE_COLOR_PICKER             (gtk_color_picker_get_type ())
+#define GTK_COLOR_PICKER(o)               (G_TYPE_CHECK_INSTANCE_CAST ((o), GTK_TYPE_COLOR_PICKER, GtkColorPicker))
+#define GTK_IS_COLOR_PICKER(o)            (G_TYPE_CHECK_INSTANCE_TYPE ((o), GTK_TYPE_COLOR_PICKER))
+#define GTK_COLOR_PICKER_GET_INTERFACE(o) (G_TYPE_INSTANCE_GET_INTERFACE ((o), GTK_TYPE_COLOR_PICKER, GtkColorPickerInterface))
+
+
+typedef struct _GtkColorPicker            GtkColorPicker;
+typedef struct _GtkColorPickerInterface   GtkColorPickerInterface;
+
+struct _GtkColorPickerInterface {
+  GTypeInterface g_iface;
+
+  void (* pick)             (GtkColorPicker      *picker,
+                             GAsyncReadyCallback  callback,
+                             gpointer             user_data);
+
+  GdkRGBA * (* pick_finish) (GtkColorPicker      *picker,
+                             GAsyncResult        *res,
+                             GError             **error);
+};
+
+GDK_AVAILABLE_IN_ALL
+GType            gtk_color_picker_get_type    (void) G_GNUC_CONST;
+GDK_AVAILABLE_IN_ALL
+GtkColorPicker * gtk_color_picker_new         (void);
+GDK_AVAILABLE_IN_ALL
+void             gtk_color_picker_pick        (GtkColorPicker       *picker,
+                                               GAsyncReadyCallback   callback,
+                                               gpointer              user_data);
+GDK_AVAILABLE_IN_ALL
+GdkRGBA *        gtk_color_picker_pick_finish (GtkColorPicker       *picker,
+                                               GAsyncResult         *res,
+                                               GError              **error);
+
+G_END_DECLS
+
+#endif  /* __GTK_COLOR_PICKER_H__ */

gtk/gtkcolorpickershell.c

@@ -0,0 +1,183 @@
+/* GTK - The GIMP Toolkit
+ * Copyright (C) 2018, Red Hat, Inc
+ *
+ * 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 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 <http://www.gnu.org/licenses/>.
+ */
+
+#include "config.h"
+
+#include "gtkcolorpickershellprivate.h"
+#include <gio/gio.h>
+
+struct _GtkColorPickerShell
+{
+  GObject parent_instance;
+
+  GDBusProxy *shell_proxy;
+  GTask *task;
+};
+
+struct _GtkColorPickerShellClass
+{
+  GObjectClass parent_class;
+};
+
+static GInitableIface *initable_parent_iface;
+static void gtk_color_picker_shell_initable_iface_init (GInitableIface *iface);
+static void gtk_color_picker_shell_iface_init (GtkColorPickerInterface *iface);
+
+G_DEFINE_TYPE_WITH_CODE (GtkColorPickerShell, gtk_color_picker_shell, G_TYPE_OBJECT,
+                         G_IMPLEMENT_INTERFACE (G_TYPE_INITABLE, gtk_color_picker_shell_initable_iface_init)
+                         G_IMPLEMENT_INTERFACE (GTK_TYPE_COLOR_PICKER, gtk_color_picker_shell_iface_init))
+
+static gboolean
+gtk_color_picker_shell_initable_init (GInitable     *initable,
+                                      GCancellable  *cancellable,
+                                      GError       **error)
+{
+  GtkColorPickerShell *picker = GTK_COLOR_PICKER_SHELL (initable);
+  char *owner;
+
+  picker->shell_proxy = g_dbus_proxy_new_for_bus_sync (G_BUS_TYPE_SESSION,
+                                                        G_DBUS_PROXY_FLAGS_NONE,
+                                                        NULL,
+                                                        "org.gnome.Shell.Screenshot",
+                                                        "/org/gnome/Shell/Screenshot",
+                                                        "org.gnome.Shell.Screenshot",
+                                                        NULL,
+                                                        error);
+
+  if (picker->shell_proxy == NULL)
+    {
+      g_warning ("No shell screenshot proxy: %s", (*error)->message);
+      return FALSE;
+    }
+
+  owner = g_dbus_proxy_get_name_owner (picker->shell_proxy);
+  if (owner == NULL)
+    {
+      g_warning ("No shell screenshot proxy");
+      g_clear_object (&picker->shell_proxy);
+      return FALSE;
+    }
+  g_free (owner);
+
+  return TRUE;
+}
+
+static void
+gtk_color_picker_shell_initable_iface_init (GInitableIface *iface)
+{
+  initable_parent_iface = g_type_interface_peek_parent (iface);
+  iface->init = gtk_color_picker_shell_initable_init;
+}
+
+static void
+gtk_color_picker_shell_init (GtkColorPickerShell *picker)
+{
+}
+
+static void
+gtk_color_picker_shell_finalize (GObject *object)
+{
+  GtkColorPickerShell *picker = GTK_COLOR_PICKER_SHELL (object);
+
+  g_clear_object (&picker->shell_proxy);
+
+  G_OBJECT_CLASS (gtk_color_picker_shell_parent_class)->finalize (object);
+}
+
+static void
+gtk_color_picker_shell_class_init (GtkColorPickerShellClass *class)
+{
+  GObjectClass *object_class = G_OBJECT_CLASS (class);
+
+  object_class->finalize = gtk_color_picker_shell_finalize;
+}
+
+GtkColorPicker *
+gtk_color_picker_shell_new (void)
+{
+  return GTK_COLOR_PICKER (g_initable_new (GTK_TYPE_COLOR_PICKER_SHELL, NULL, NULL, NULL));
+}
+
+static void
+color_picked (GObject      *source,
+              GAsyncResult *res,
+              gpointer      data)
+{
+  GtkColorPickerShell *picker = GTK_COLOR_PICKER_SHELL (data);
+  GError *error = NULL;
+  GVariant *ret;
+
+  ret = g_dbus_proxy_call_finish (picker->shell_proxy, res, &error);
+
+  if (ret == NULL)
+    {
+      g_task_return_error (picker->task, error);
+    }
+  else
+    {
+      GdkRGBA c;
+
+      c.alpha = 1;
+      if (!g_variant_lookup (ret, "color", "(ddd)", &c.red, &c.green, &c.blue))
+        g_task_return_new_error (picker->task, G_IO_ERROR, G_IO_ERROR_FAILED, "No color received");
+      else
+        g_task_return_pointer (picker->task, gdk_rgba_copy (&c), (GDestroyNotify)gdk_rgba_free);
+
+      g_variant_unref (ret);
+    }
+
+  g_clear_object (&picker->task);
+}
+
+static void
+gtk_color_picker_shell_pick (GtkColorPicker      *cp,
+                             GAsyncReadyCallback  callback,
+                             gpointer             user_data)
+{
+  GtkColorPickerShell *picker = GTK_COLOR_PICKER_SHELL (cp);
+
+  if (picker->task)
+    return;
+
+  picker->task = g_task_new (picker, NULL, callback, user_data);
+
+  g_dbus_proxy_call (picker->shell_proxy,
+                     "PickColor",
+                     NULL,
+                     0,
+                     -1,
+                     NULL,
+                     color_picked,
+                     picker);
+}
+
+static GdkRGBA *
+gtk_color_picker_shell_pick_finish (GtkColorPicker  *cp,
+                                     GAsyncResult    *res,
+                                     GError         **error)
+{
+  g_return_val_if_fail (g_task_is_valid (res, cp), NULL);
+
+  return g_task_propagate_pointer (G_TASK (res), error);
+}
+
+static void
+gtk_color_picker_shell_iface_init (GtkColorPickerInterface *iface)
+{
+  iface->pick = gtk_color_picker_shell_pick;
+  iface->pick_finish = gtk_color_picker_shell_pick_finish;
+}

gtk/gtkcolorpickershellprivate.h

@@ -0,0 +1,41 @@
+/*
+ * GTK - The GIMP Toolkit
+ * Copyright (C) 2018 Red Hat, Inc.
+ * All rights reserved.
+ *
+ * This Library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Library General Public License as
+ * published by the Free Software Foundation; either version 2 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
+ * Library General Public License for more details.
+ *
+ * You should have received a copy of the GNU Library General Public
+ * License along with this library. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef __GTK_COLOR_PICKER_SHELL_H__
+#define __GTK_COLOR_PICKER_SHELL_H__
+
+
+#if !defined (__GTK_H_INSIDE__) && !defined (GTK_COMPILATION)
+#error "Only <gtk/gtk.h> can be included directly."
+#endif
+
+#include <gtk/gtkcolorpickerprivate.h>
+
+G_BEGIN_DECLS
+
+
+#define GTK_TYPE_COLOR_PICKER_SHELL gtk_color_picker_shell_get_type ()
+G_DECLARE_FINAL_TYPE (GtkColorPickerShell, gtk_color_picker_shell, GTK, COLOR_PICKER_SHELL, GObject)
+
+GDK_AVAILABLE_IN_ALL
+GtkColorPicker * gtk_color_picker_shell_new (void);
+
+G_END_DECLS
+
+#endif  /* __GTK_COLOR_PICKER_SHELL_H__ */

gtk/meson.build

@@ -30,6 +30,9 @@ gtk_private_sources = files([
   'gtkcellareaboxcontext.c',
   'gtkcoloreditor.c',
   'gtkcolorplane.c',
+  'gtkcolorpicker.c',
+  'gtkcolorpickerportal.c',
+  'gtkcolorpickershell.c',
   'gtkcolorscale.c',
   'gtkcolorswatch.c',
   'gtkcssanimatedstyle.c',

gtk/ui/gtkcoloreditor.ui

@@ -38,6 +38,19 @@
             <property name="margin-end">30</property>
             <property name="row-spacing">12</property>
             <property name="column-spacing">12</property>
+            <child>
+              <object class="GtkButton" id="picker_button">
+                <property name="can-focus">1</property>
+                <property name="relief">none</property>
+                <property name="icon-name">color-select-symbolic</property>
+                <property name="tooltip-text" translatable="yes">Pick a color from the screen</property>
+                <signal name="clicked" handler="pick_color"/>
+              </object>
+              <packing>
+                <property name="left-attach">0</property>
+                <property name="top-attach">0</property>
+              </packing>
+            </child>
             <child>
               <object class="GtkColorSwatch" id="swatch">
                 <property name="name">editor-color-sample</property>