[pitivi] project: Fix w/h UI update when a preset is selected and link is checked

[Thibault Saunier <tsaunier src gnome org>]

commit 2fcf8cd07449a359e78d1857206368c0a81f658b
Author: Alexandru Băluț <alexandru balut gmail com>
Date:   Thu May 7 08:27:00 2015 +0200

    project: Fix w/h UI update when a preset is selected and link is checked
    
    The bug manifests when the width and height are linked and you select
    a different preset, then right away the height is updated based on the
    preset's width and the *old* w/h fraction.

 pitivi/preset.py  |   26 ++++++++++++++------------
 pitivi/project.py |   16 +++++++++-------
 2 files changed, 23 insertions(+), 19 deletions(-)
---
diff --git a/pitivi/preset.py b/pitivi/preset.py
index f1ff147..306bd43 100644
--- a/pitivi/preset.py
+++ b/pitivi/preset.py
@@ -67,7 +67,7 @@ class PresetManager(object):
         self.ordered = Gtk.ListStore(str, object)
         self.cur_preset = None
         # Whether to ignore the updateValue calls.
-        self._ignore_update_requests = False
+        self.ignore_update_requests = False
         self.system = system.getSystem()
 
     def loadAll(self):
@@ -180,7 +180,7 @@ class PresetManager(object):
 
     def updateValue(self, name, value):
         """Update a value in the current preset, if any."""
-        if self._ignore_update_requests:
+        if self.ignore_update_requests:
             # This is caused by restorePreset, nothing to do.
             return
         if self.cur_preset:
@@ -196,20 +196,22 @@ class PresetManager(object):
         @param preset: The name of the preset to be selected.
         @type preset: str
         """
-        self._ignore_update_requests = True
         if preset is None:
             self.cur_preset = None
             return
-        elif preset not in self.presets:
+        if preset not in self.presets:
             return
-        values = self.presets[preset]
-        self.cur_preset = preset
-        for field, (setter, getter) in self.widget_map.items():
-            if values[field] != 0:
-                setter(values[field])
-            else:
-                setter(self.presets[_("No preset")][field])
-        self._ignore_update_requests = False
+        self.ignore_update_requests = True
+        try:
+            values = self.presets[preset]
+            self.cur_preset = preset
+            for field, (setter, getter) in self.widget_map.items():
+                if values[field] != 0:
+                    setter(values[field])
+                else:
+                    setter(self.presets[_("No preset")][field])
+        finally:
+            self.ignore_update_requests = False
 
     def saveCurrentPreset(self):
         """Update the current preset values from the widgets and save it."""
diff --git a/pitivi/project.py b/pitivi/project.py
index 3cb29be..aa9ecc4 100644
--- a/pitivi/project.py
+++ b/pitivi/project.py
@@ -1631,6 +1631,7 @@ class ProjectSettingsDialog():
         else:
             preset = None
         mgr.restorePreset(preset)
+        self._updateSar()
         update_preset_buttons_func()
         self._hidePresetManagerError(mgr)
 
@@ -1660,7 +1661,7 @@ class ProjectSettingsDialog():
         infobar.hide()
 
     def constrained(self):
-        return self.constrain_sar_button.props.active
+        return self.constrain_sar_button.props.active and not self.video_presets.ignore_update_requests
 
     def _updateFraction(self, unused, fraction, combo):
         fraction.setWidgetValue(get_combo_value(combo))
@@ -1673,9 +1674,11 @@ class ProjectSettingsDialog():
         height = int(self.height_spinbutton.get_value())
         return Gst.Fraction(width, height)
 
-    def _constrainSarButtonToggledCb(self, button):
-        if button.props.active:
-            self.sar = self.getSAR()
+    def _constrainSarButtonToggledCb(self, unused_button):
+        self._updateSar()
+
+    def _updateSar(self):
+        self.sar = self.getSAR()
 
     def _selectDarRadiobuttonToggledCb(self, button):
         state = button.props.active
@@ -1768,7 +1771,7 @@ class ProjectSettingsDialog():
 
     def updateHeight(self):
         width = int(self.width_spinbutton.get_value())
-        self.height_spinbutton.set_value(width * (1 / self.sar))
+        self.height_spinbutton.set_value(width / self.sar)
 
     def updateDarFromPar(self):
         par = self.par_fraction_widget.getWidgetValue()
@@ -1778,7 +1781,7 @@ class ProjectSettingsDialog():
     def updateParFromDar(self):
         dar = self.dar_fraction_widget.getWidgetValue()
         sar = self.getSAR()
-        self.par_fraction_widget.setWidgetValue(dar * (1 / sar))
+        self.par_fraction_widget.setWidgetValue(dar / sar)
 
     def updateDarFromCombo(self):
         self.dar_fraction_widget.setWidgetValue(
@@ -1797,7 +1800,6 @@ class ProjectSettingsDialog():
             self.par_combo, self.par_fraction_widget.getWidgetValue())
 
     def updateUI(self):
-
         self.width_spinbutton.set_value(self.project.videowidth)
         self.height_spinbutton.set_value(self.project.videoheight)