[pitivi] elements: Remove unuseful tooltip

[Alexandru Băluț <alexbalut src gnome org>]

commit 7319d3a6d02f9f01b11eb805d0b55dc77ff8e999
Author: Alexandru Băluț <alexandru balut gmail com>
Date:   Thu Aug 11 01:12:25 2016 +0200

    elements: Remove unuseful tooltip
    
    The "Setting property: <property>" is not useful because when it's
    displayed the user does not interact with the keyframe curve.
    
    Now the tooltip appears only when the keyframe curve is hovered,
    otherwise the clip's tooltip appears showing the name of the clip.
    
    Reviewed-by: Thibault Saunier <tsaunier gnome org>
    Differential Revision: https://phabricator.freedesktop.org/D1273

 pitivi/timeline/elements.py |   30 +++++++++++++++++-------------
 1 files changed, 17 insertions(+), 13 deletions(-)
---
diff --git a/pitivi/timeline/elements.py b/pitivi/timeline/elements.py
index d23d664..4aa44a7 100644
--- a/pitivi/timeline/elements.py
+++ b/pitivi/timeline/elements.py
@@ -95,7 +95,6 @@ class KeyframeCurve(FigureCanvas, Loggable):
         self.__source.connect("value-changed", self.__controlSourceChangedCb)
         self.__propertyName = binding.props.name
         self.__paramspec = binding.pspec
-        self.__resetTooltip()
         self.get_style_context().add_class("KeyframeCurve")
 
         self.__ylim_min, self.__ylim_max = KeyframeCurve.YLIM_OVERRIDES.get(
@@ -298,7 +297,7 @@ class KeyframeCurve(FigureCanvas, Loggable):
                 ydata = max(self.__ylim_min, min(event.ydata, self.__ylim_max))
                 self.__source.set(keyframe_ts, ydata)
                 self.__offset = keyframe_ts
-                self.__setTooltip(event)
+                self.__update_tooltip(event)
                 hovering = True
             elif self.__clicked_line:
                 self.__dragged = True
@@ -315,7 +314,7 @@ class KeyframeCurve(FigureCanvas, Loggable):
 
         if hovering:
             cursor = DRAG_CURSOR
-            self.__setTooltip(event)
+            self.__update_tooltip(event)
             if not self.__hovered:
                 self.emit("enter")
                 self.__hovered = True
@@ -323,7 +322,7 @@ class KeyframeCurve(FigureCanvas, Loggable):
             cursor = NORMAL_CURSOR
             if self.__hovered:
                 self.emit("leave")
-                self.__resetTooltip()
+                self.__update_tooltip(None)
                 self.__hovered = False
 
         self.__timeline.get_window().set_cursor(cursor)
@@ -353,21 +352,26 @@ class KeyframeCurve(FigureCanvas, Loggable):
             else:
                 self.__keyframe_removed = False
 
-    def __setTooltip(self, event):
-        if event.xdata:
+    def __update_tooltip(self, event):
+        """Sets or clears the tooltip showing info about the hovered line."""
+        markup = None
+        if event:
+            if not event.xdata:
+                return
             xdata = max(self.__line_xs[0], min(event.xdata, self.__line_xs[-1]))
             res, value = self.__source.control_source_get_value(xdata)
             assert res
             pmin = self.__paramspec.minimum
             pmax = self.__paramspec.maximum
             value = value * (pmax - pmin) + pmin
-            self.set_tooltip_markup(_("Property: %s\nTimestamp: %s\nValue: %s")
-                                    % (self.__propertyName,
-                                       Gst.TIME_ARGS(xdata),
-                                       "{:.3f}".format(value)))
-
-    def __resetTooltip(self):
-        self.set_tooltip_markup(_("Setting property: %s") % self.__propertyName)
+            # Translators: This is a tooltip for a clip's keyframe curve,
+            # showing what the keyframe curve affects, the timestamp at
+            # the mouse cursor location, and the value at that timestamp.
+            markup = _("Property: %s\nTimestamp: %s\nValue: %s") % (
+                self.__propertyName,
+                Gst.TIME_ARGS(xdata),
+                "{:.3f}".format(value))
+        self.set_tooltip_markup(markup)
 
     def __computeKeyframeNewTimestamp(self, event):
         # The user can not change the timestamp of the first