Refactor and fix zoom handling

ColumnManager has to apply the zoom factor to newly added columns. Otherwise,
showing a previously hidden column appears with scale 1.0.

This also drops the value-changed signal emission for the vadjustment, as it is
apparently not needed.

2 files changed, 32 insertions, 10 deletions

diff --git a/GstDebugViewer/GUI/columns.py b/GstDebugViewer/GUI/columns.py
index 62df7f3..0579a41 100644
--- a/GstDebugViewer/GUI/columns.py
+++ b/GstDebugViewer/GUI/columns.py
@@ -377,6 +377,7 @@ class ColumnManager (Common.GUI.Manager):
 
         self.view = None
         self.actions = None
+        self.zoom = 1.0
         self.__columns_changed_id = None
         self.columns = []
         self.column_order = list (self.column_classes)
@@ -450,6 +451,15 @@ class ColumnManager (Common.GUI.Manager):
         sort_model.set_sort_column_id (TREE_SORTABLE_UNSORTED_COLUMN_ID,
                                        gtk.SORT_ASCENDING)
 
+    def set_zoom (self, scale):
+
+        for column in self.columns:
+            cell = column.view_column.get_cell_renderers ()[0]
+            cell.props.scale = scale
+            column.view_column.queue_resize ()
+
+        self.zoom = scale
+
     def get_toggle_action (self, column_class):
 
         action_name = "show-%s-column" % (column_class.name,)
@@ -463,8 +473,13 @@ class ColumnManager (Common.GUI.Manager):
 
         name = column.name
         pos = self.__get_column_insert_position (column)
+
         if self.view.props.fixed_height_mode:
             column.view_column.props.sizing = gtk.TREE_VIEW_COLUMN_FIXED
+
+        cell = column.view_column.get_cell_renderers ()[0]
+        cell.props.scale = self.zoom
+
         self.columns.insert (pos, column)
         self.view.insert_column (column.view_column, pos)
 
diff --git a/GstDebugViewer/GUI/window.py b/GstDebugViewer/GUI/window.py
index ee3437d..411c155 100644
--- a/GstDebugViewer/GUI/window.py
+++ b/GstDebugViewer/GUI/window.py
@@ -19,6 +19,8 @@
 
 """GStreamer Debug Viewer GUI module."""
 
+ZOOM_FACTOR = 1.15
+
 def _ (s):
     return s
 
@@ -286,6 +288,7 @@ class Window (object):
 
     def attach (self):
 
+        self.zoom_level = 0
         self.window_state.attach (window = self.gtk_window,
                                   state = self.app.state_section)
 
@@ -577,18 +580,22 @@ class Window (object):
         self.clipboard.set_text (self.get_active_line ()[col_id])
 
     def handle_enlarge_text_action_activate (self, action):
-        for col in self.column_manager.columns:
-            cell = col.view_column.get_cell_renderers ()[0]
-            cell.props.scale *= 1.15
-            col.view_column.queue_resize ()
-        self.widgets.log_view_scrolled_window.props.vadjustment.emit ("value-changed")
+
+        self.update_zoom_level (1)
 
     def handle_shrink_text_action_activate (self, action):
-        for col in self.column_manager.columns:
-            cell = col.view_column.get_cell_renderers ()[0]
-            cell.props.scale /= 1.15
-            col.view_column.queue_resize ()
-        self.widgets.log_view_scrolled_window.props.vadjustment.emit ("value-changed")
+
+        self.update_zoom_level (-1)
+
+    def update_zoom_level (self, delta_step):
+
+        if not delta_step:
+            return
+
+        self.zoom_level += delta_step
+        scale = ZOOM_FACTOR ** self.zoom_level
+
+        self.column_manager.set_zoom (scale)
 
     def add_model_filter (self, filter):