[retro-gtk] video-filter: Add from_string()

[Adrien Plazas <aplazas src gnome org>]

commit cdca751ab3d6f34791f5d6e972c9f3ebbf1d9909
Author: theawless <theawless gmail com>
Date:   Tue Feb 21 00:30:39 2017 +0530

    video-filter: Add from_string()
    
    Parse the string to get the corresponding filter. In case of a failure,
    return the default one.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=777987

 retro-gtk/video/video-filter.vala |    9 ++++++++-
 1 files changed, 8 insertions(+), 1 deletions(-)
---
diff --git a/retro-gtk/video/video-filter.vala b/retro-gtk/video/video-filter.vala
index 218359b..17b135b 100644
--- a/retro-gtk/video/video-filter.vala
+++ b/retro-gtk/video/video-filter.vala
@@ -2,5 +2,12 @@
 
 public enum Retro.VideoFilter {
        SMOOTH,
-       SHARP,
+       SHARP;
+
+       public static VideoFilter from_string (string filter) {
+               var enumc = (EnumClass) typeof (VideoFilter).class_ref ();
+               var eval = enumc.get_value_by_nick (filter);
+
+               return eval == null ? VideoFilter.SMOOTH : (VideoFilter) eval.value;
+       }
 }