[gnome-control-center] shortcut-editor: use states to handle headerbar mode

[Bastien Nocera <hadess src gnome org>]

commit 40ee2253856bf1eb727206210f39f397045d2ba2
Author: Georges Basile Stavracas Neto <georges stavracas gmail com>
Date:   Tue Aug 30 11:43:43 2016 -0300

    shortcut-editor: use states to handle headerbar mode
    
    Instead of manually handling every button in the headerbar
    individually, using states to switch between modes. It's clearer
    and easier to maintain.
    
    This patch adds the headerbar mode handling code, and updates
    the current code to use it rather than by updating each individual
    button manually.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=769314

 panels/keyboard/cc-keyboard-shortcut-editor.c |   68 ++++++++++++++++---------
 1 files changed, 43 insertions(+), 25 deletions(-)
---
diff --git a/panels/keyboard/cc-keyboard-shortcut-editor.c b/panels/keyboard/cc-keyboard-shortcut-editor.c
index e9f9005..33d37bd 100644
--- a/panels/keyboard/cc-keyboard-shortcut-editor.c
+++ b/panels/keyboard/cc-keyboard-shortcut-editor.c
@@ -83,6 +83,16 @@ enum
   N_PROPS
 };
 
+typedef enum
+{
+  HEADER_MODE_NONE,
+  HEADER_MODE_ADD,
+  HEADER_MODE_SET,
+  HEADER_MODE_REPLACE,
+  HEADER_MODE_CUSTOM_CANCEL,
+  HEADER_MODE_CUSTOM_EDIT
+} HeaderMode;
+
 static GParamSpec *properties [N_PROPS] = { NULL, };
 
 static void
@@ -128,8 +138,6 @@ clear_custom_entries (CcKeyboardShortcutEditor *self)
   gtk_entry_set_text (GTK_ENTRY (self->name_entry), "");
   gtk_entry_set_text (GTK_ENTRY (self->command_entry), "");
 
-  gtk_widget_set_sensitive (self->add_button, FALSE);
-
   gtk_shortcut_label_set_accelerator (GTK_SHORTCUT_LABEL (self->custom_shortcut_accel_label), "");
   gtk_label_set_label (GTK_LABEL (self->new_shortcut_conflict_label), "");
   gtk_label_set_label (GTK_LABEL (self->shortcut_conflict_label), "");
@@ -233,13 +241,16 @@ get_current_shortcut_label (CcKeyboardShortcutEditor *self)
 }
 
 static void
-set_collision_headerbar (CcKeyboardShortcutEditor *self,
-                         gboolean                  has_collision)
+set_header_mode (CcKeyboardShortcutEditor *self,
+                 HeaderMode                mode)
 {
-  gtk_header_bar_set_show_close_button (GTK_HEADER_BAR (self->headerbar), !has_collision);
+  gtk_header_bar_set_show_close_button (GTK_HEADER_BAR (self->headerbar), mode == HEADER_MODE_CUSTOM_EDIT);
 
-  gtk_widget_set_visible (self->cancel_button, has_collision);
-  gtk_widget_set_visible (self->replace_button, has_collision);
+  gtk_widget_set_visible (self->add_button, mode == HEADER_MODE_ADD);
+  gtk_widget_set_visible (self->cancel_button, mode != HEADER_MODE_NONE &&
+                                               mode != HEADER_MODE_CUSTOM_EDIT);
+  gtk_widget_set_visible (self->replace_button, mode == HEADER_MODE_REPLACE);
+  gtk_widget_set_visible (self->set_button, mode == HEADER_MODE_SET);
 }
 
 static void
@@ -247,23 +258,30 @@ setup_custom_shortcut (CcKeyboardShortcutEditor *self)
 {
   GtkShortcutLabel *shortcut_label;
   CcKeyboardItem *collision_item;
+  HeaderMode mode;
+  gboolean is_custom;
   gboolean valid;
   gchar *accel;
 
+  is_custom = is_custom_shortcut (self);
   valid = is_valid_binding (self->custom_keyval, self->custom_mask, self->custom_keycode) &&
           gtk_accelerator_valid (self->custom_keyval, self->custom_mask) &&
           !self->custom_is_modifier;
 
   /* Additional checks for custom shortcuts */
-  if (is_custom_shortcut (self))
+  if (is_custom)
     {
       valid = valid &&
               gtk_entry_get_text_length (GTK_ENTRY (self->name_entry)) > 0 &&
               gtk_entry_get_text_length (GTK_ENTRY (self->command_entry)) > 0;
     }
 
-  gtk_widget_set_sensitive (self->add_button, valid);
+  if (valid)
+    set_header_mode (self, HEADER_MODE_ADD);
+  else
+    set_header_mode (self, is_custom ? HEADER_MODE_CUSTOM_CANCEL : HEADER_MODE_NONE);
 
+  /* Nothing else to do if the shortcut is invalid */
   if (!valid)
     return;
 
@@ -328,8 +346,19 @@ setup_custom_shortcut (CcKeyboardShortcutEditor *self)
    * the headerbar to display "Cancel" and "Replace". Otherwise, make sure to set
    * only the close button again.
    */
-  if (self->mode == CC_SHORTCUT_EDITOR_EDIT)
-    set_collision_headerbar (self, collision_item != NULL);
+  if (collision_item)
+    {
+      mode = HEADER_MODE_REPLACE;
+    }
+  else
+    {
+      if (self->mode == CC_SHORTCUT_EDITOR_EDIT)
+        mode = is_custom ? HEADER_MODE_CUSTOM_EDIT : HEADER_MODE_SET;
+      else
+        mode = is_custom ? HEADER_MODE_ADD : HEADER_MODE_SET;
+    }
+
+  set_header_mode (self, mode);
 
   self->collision_item = collision_item;
 
@@ -445,7 +474,8 @@ setup_keyboard_item (CcKeyboardShortcutEditor *self,
   /* Headerbar */
   gtk_header_bar_set_title (GTK_HEADER_BAR (self->headerbar),
                             is_custom ? _("Set Custom Shortcut") : _("Set Shortcut"));
-  gtk_header_bar_set_show_close_button (GTK_HEADER_BAR (self->headerbar), TRUE);
+
+  set_header_mode (self, is_custom ? HEADER_MODE_CUSTOM_EDIT : HEADER_MODE_NONE);
 
   gtk_widget_hide (self->add_button);
   gtk_widget_hide (self->cancel_button);
@@ -792,9 +822,6 @@ cc_keyboard_shortcut_editor_set_mode (CcKeyboardShortcutEditor *self,
 
   g_return_if_fail (CC_IS_KEYBOARD_SHORTCUT_EDITOR (self));
 
-  if (self->mode == mode)
-    return;
-
   self->mode = mode;
   is_create_mode = mode == CC_SHORTCUT_EDITOR_CREATE;
 
@@ -805,18 +832,9 @@ cc_keyboard_shortcut_editor_set_mode (CcKeyboardShortcutEditor *self,
       /* Cleanup whatever was set before */
       clear_custom_entries (self);
 
-      /* The 'Add' button is only sensitive when the shortcut is valid */
-      gtk_widget_set_sensitive (self->add_button, FALSE);
-
-      gtk_header_bar_set_show_close_button (GTK_HEADER_BAR (self->headerbar), FALSE);
+      set_header_mode (self, HEADER_MODE_CUSTOM_CANCEL);
       gtk_header_bar_set_title (GTK_HEADER_BAR (self->headerbar), _("Add Custom Shortcut"));
 
       gtk_stack_set_visible_child_name (GTK_STACK (self->stack), "custom");
-
-      gtk_widget_show (self->add_button);
-      gtk_widget_show (self->cancel_button);
-
-      gtk_widget_hide (self->remove_button);
-      gtk_widget_hide (self->replace_button);
     }
 }