[gimp/gimp-2-10] app: in the transform tools, blink type box when there's no item to transform

[Ell <ell src gnome org>]

commit a42f2cb2e7e769d6ed8a701d8dbc94708f5c8a85
Author: Ell <ell_se yahoo com>
Date:   Mon Dec 10 07:39:32 2018 -0500

    app: in the transform tools, blink type box when there's no item to transform
    
    In the transform tools, when there is no item of the selected type
    to transform, blink the move-type box widget in the tool options,
    in addition to showing an error message in the status bar, to hint
    at the source of the error.
    
    (cherry picked from commit 17412aa234f87b0236ae8692fa856deaf6e8a14f)

 app/tools/gimptransformoptions.c | 17 ++++++++++-------
 app/tools/gimptransformoptions.h | 13 ++++++++-----
 app/tools/gimptransformtool.c    |  3 +++
 3 files changed, 21 insertions(+), 12 deletions(-)
---
diff --git a/app/tools/gimptransformoptions.c b/app/tools/gimptransformoptions.c
index 4342318707..a9311c98f7 100644
--- a/app/tools/gimptransformoptions.c
+++ b/app/tools/gimptransformoptions.c
@@ -214,18 +214,21 @@ gimp_transform_options_gui (GimpToolOptions *tool_options,
                             gboolean         interpolation,
                             gboolean         clipping)
 {
-  GObject         *config = G_OBJECT (tool_options);
-  GtkWidget       *vbox   = gimp_tool_options_gui (tool_options);
-  GtkWidget       *hbox;
-  GtkWidget       *box;
-  GtkWidget       *label;
-  GtkWidget       *frame;
-  GtkWidget       *combo;
+  GObject              *config  = G_OBJECT (tool_options);
+  GimpTransformOptions *options = GIMP_TRANSFORM_OPTIONS (tool_options);
+  GtkWidget            *vbox    = gimp_tool_options_gui (tool_options);
+  GtkWidget            *hbox;
+  GtkWidget            *box;
+  GtkWidget            *label;
+  GtkWidget            *frame;
+  GtkWidget            *combo;
 
   hbox = gtk_box_new (GTK_ORIENTATION_HORIZONTAL, 2);
   gtk_box_pack_start (GTK_BOX (vbox), hbox, FALSE, FALSE, 0);
   gtk_widget_show (hbox);
 
+  options->type_box = hbox;
+
   label = gtk_label_new (_("Transform:"));
   gtk_box_pack_start (GTK_BOX (hbox), label, FALSE, FALSE, 0);
   gtk_widget_show (label);
diff --git a/app/tools/gimptransformoptions.h b/app/tools/gimptransformoptions.h
index 621087ed1b..e5a42acd96 100644
--- a/app/tools/gimptransformoptions.h
+++ b/app/tools/gimptransformoptions.h
@@ -35,12 +35,15 @@ typedef struct _GimpTransformOptionsClass GimpTransformOptionsClass;
 
 struct _GimpTransformOptions
 {
-  GimpToolOptions        parent_instance;
+  GimpToolOptions         parent_instance;
 
-  GimpTransformType      type;
-  GimpTransformDirection direction;
-  GimpInterpolationType  interpolation;
-  GimpTransformResize    clip;
+  GimpTransformType       type;
+  GimpTransformDirection  direction;
+  GimpInterpolationType   interpolation;
+  GimpTransformResize     clip;
+
+  /*  options gui  */
+  GtkWidget              *type_box;
 };
 
 struct _GimpTransformOptionsClass
diff --git a/app/tools/gimptransformtool.c b/app/tools/gimptransformtool.c
index 284e1ca863..c91f6d0883 100644
--- a/app/tools/gimptransformtool.c
+++ b/app/tools/gimptransformtool.c
@@ -43,6 +43,7 @@
 
 #include "widgets/gimpmessagedialog.h"
 #include "widgets/gimpmessagebox.h"
+#include "widgets/gimpwidgets-utils.h"
 
 #include "gimptoolcontrol.h"
 #include "gimptransformoptions.h"
@@ -560,6 +561,8 @@ gimp_transform_tool_check_active_item (GimpTransformTool  *tr_tool,
   if (! item)
     {
       g_set_error_literal (error, GIMP_ERROR, GIMP_FAILED, null_message);
+      if (error)
+        gimp_widget_blink (options->type_box);
       return NULL;
     }