[gimp] gui: #1140 Add image size template selector to resize canvas dialog

[Jehan <jehanp src gnome org>]

commit a6037760dacb58081713523f3faab007937973df
Author: Stanislav Grinkov <43956-stanislavgrinkov users noreply gitlab gnome org>
Date:   Mon Jan 25 02:03:25 2021 +0600

    gui: #1140 Add image size template selector to resize canvas dialog
    
    Adds option for selecting predefined page sizes using the same
    template selector as on "New Image" dialog.
    
    Syncs up size and offset unit selectors to have the same value
    when changing template and when resetting whole dialog.

 app/dialogs/resize-dialog.c | 81 +++++++++++++++++++++++++++++++++++++++++++--
 1 file changed, 79 insertions(+), 2 deletions(-)
---
diff --git a/app/dialogs/resize-dialog.c b/app/dialogs/resize-dialog.c
index fb452731b2..c4e72db686 100644
--- a/app/dialogs/resize-dialog.c
+++ b/app/dialogs/resize-dialog.c
@@ -26,10 +26,13 @@
 
 #include "dialogs-types.h"
 
+#include "core/gimp.h"
 #include "core/gimpcontext.h"
 #include "core/gimpimage.h"
 #include "core/gimplayer.h"
+#include "core/gimptemplate.h"
 
+#include "widgets/gimpcontainercombobox.h"
 #include "widgets/gimphelp-ids.h"
 #include "widgets/gimpsizebox.h"
 #include "widgets/gimpviewabledialog.h"
@@ -49,6 +52,7 @@ struct _ResizeDialog
 {
   GimpViewable       *viewable;
   GimpContext        *context;
+  GimpContext        *parent_context;
   GimpFillType        fill_type;
   GimpItemSet         layer_set;
   gboolean            resize_text_layers;
@@ -91,6 +95,9 @@ static void   offsets_changed        (GtkWidget    *area,
 static void   offset_center_clicked  (GtkWidget    *widget,
                                       ResizeDialog *private);
 
+static void   template_changed       (GimpContext  *context,
+                                      GimpTemplate *template,
+                                      ResizeDialog *private);
 
 /*  public function  */
 
@@ -119,6 +126,8 @@ resize_dialog_new (GimpViewable       *viewable,
   GtkWidget     *entry;
   GtkWidget     *hbox;
   GtkWidget     *combo;
+  GtkWidget     *label;
+  GtkWidget     *template_selector;
   GtkAdjustment *adjustment;
   GdkPixbuf     *pixbuf;
   GtkSizeGroup  *size_group   = NULL;
@@ -161,8 +170,12 @@ resize_dialog_new (GimpViewable       *viewable,
 
   private = g_slice_new0 (ResizeDialog);
 
+  private->parent_context = context;
+  private->context        = gimp_context_new (context->gimp,
+                                              "resize-dialog",
+                                              context);
+
   private->viewable           = viewable;
-  private->context            = context;
   private->fill_type          = fill_type;
   private->layer_set          = layer_set;
   private->resize_text_layers = resize_text_layers;
@@ -176,6 +189,8 @@ resize_dialog_new (GimpViewable       *viewable,
   private->old_layer_set          = private->layer_set;
   private->old_resize_text_layers = private->resize_text_layers;
 
+  gimp_context_set_template (private->context, NULL);
+
   dialog = gimp_viewable_dialog_new (g_list_prepend (NULL, viewable), context,
                                      title, role, GIMP_ICON_OBJECT_RESIZE, title,
                                      parent,
@@ -208,10 +223,40 @@ resize_dialog_new (GimpViewable       *viewable,
                       main_vbox, TRUE, TRUE, 0);
   gtk_widget_show (main_vbox);
 
+  /* template selector */
+  hbox = gtk_box_new (GTK_ORIENTATION_HORIZONTAL, 6);
+  gtk_box_pack_start (GTK_BOX (main_vbox), hbox, FALSE, FALSE, 0);
+  gtk_widget_show (hbox);
+
+  label = gtk_label_new_with_mnemonic (_("_Template:"));
+  gtk_box_pack_start (GTK_BOX (hbox), label, FALSE, FALSE, 0);
+  gtk_widget_show (label);
+
+  template_selector = g_object_new (GIMP_TYPE_CONTAINER_COMBO_BOX,
+                                    "container",         context->gimp->templates,
+                                    "context",           private->context,
+                                    "view-size",         16,
+                                    "view-border-width", 0,
+                                    "ellipsize",         PANGO_ELLIPSIZE_NONE,
+                                    "focus-on-click",    FALSE,
+                                    NULL);
+
+  gtk_box_pack_start (GTK_BOX (hbox), template_selector, TRUE, TRUE, 0);
+  gtk_widget_show (template_selector);
+
+  gtk_label_set_mnemonic_widget (GTK_LABEL (label), template_selector);
+
+  g_signal_connect (private->context,
+                    "template-changed",
+                    G_CALLBACK (template_changed),
+                    private);
+
+  /* size select frame */
   frame = gimp_frame_new (size_title);
   gtk_box_pack_start (GTK_BOX (main_vbox), frame, FALSE, FALSE, 0);
   gtk_widget_show (frame);
 
+  /* size box */
   gimp_image_get_resolution (image, &xres, &yres);
 
   private->box = g_object_new (GIMP_TYPE_SIZE_BOX,
@@ -392,6 +437,8 @@ resize_dialog_new (GimpViewable       *viewable,
 static void
 resize_dialog_free (ResizeDialog *private)
 {
+  g_object_unref (private->context);
+
   g_slice_free (ResizeDialog, private);
 }
 
@@ -420,7 +467,7 @@ resize_dialog_response (GtkWidget    *dialog,
 
       private->callback (dialog,
                          private->viewable,
-                         private->context,
+                         private->parent_context,
                          width,
                          height,
                          unit,
@@ -461,6 +508,11 @@ resize_dialog_reset (ResizeDialog *private)
   if (private->text_layers_button)
     gtk_toggle_button_set_active (GTK_TOGGLE_BUTTON (private->text_layers_button),
                                   private->old_resize_text_layers);
+
+  gimp_context_set_template (private->context, NULL);
+
+  gimp_size_entry_set_unit (GIMP_SIZE_ENTRY (private->offset),
+                            private->old_unit);
 }
 
 static void
@@ -546,3 +598,28 @@ offset_center_clicked (GtkWidget    *widget,
 
   g_signal_emit_by_name (private->offset, "value-changed", 0);
 }
+
+static void
+template_changed (GimpContext  *context,
+                  GimpTemplate *template,
+                  ResizeDialog *private)
+{
+  gint     width;
+  gint     height;
+  GimpUnit unit;
+
+  if (! template)
+    return;
+
+  width  = gimp_template_get_width (template);
+  height = gimp_template_get_height (template);
+  unit   = gimp_template_get_unit (template);
+
+  g_object_set (private->box,
+                "width",  width,
+                "height", height,
+                "unit",   unit,
+                NULL);
+
+  gimp_size_entry_set_unit (GIMP_SIZE_ENTRY (private->offset), unit);
+}