[latexila] Search entry: red background when text not found

[Sébastien Wilmet <swilmet src gnome org>]

commit 20f732f3ecc20ff598bffdfe0c2ee4b20ad173e1
Author: Sébastien Wilmet <swilmet gnome org>
Date:   Fri Oct 4 17:19:22 2013 +0200

    Search entry: red background when text not found

 src/search.vala |   10 ++++++++++
 1 files changed, 10 insertions(+), 0 deletions(-)
---
diff --git a/src/search.vala b/src/search.vala
index 6741f5e..0eb553f 100644
--- a/src/search.vala
+++ b/src/search.vala
@@ -400,6 +400,16 @@ public class SearchAndReplace : GLib.Object
             _search_context = new SourceSearchContext (_main_window.active_document,
                 _search_settings);
 
+            _search_context.notify["occurrences-count"].connect (() =>
+            {
+                if (_search_context.occurrences_count == 0 &&
+                    _search_settings.get_search_text () != null)
+                    ErrorEntry.add_error (_entry_find);
+
+                else if (_search_context.occurrences_count >= 0)
+                    ErrorEntry.remove_error (_entry_find);
+            });
+
             bool readonly = _main_window.active_document.readonly;
             _replace_grid.set_sensitive (! readonly);
         }