Tag browser: Add an option to control the spacing between items

Also tighten the default spacing a little bit

src/calibre/gui2/__init__.py

@@ -150,6 +150,7 @@ def create_defs():
     defs['tag_browser_show_counts'] = True
     defs['row_numbers_in_book_list'] = True
     defs['hidpi'] = 'auto'
+    defs['tag_browser_item_padding'] = 0.5
 
 
 create_defs()

src/calibre/gui2/preferences/look_feel.py

@@ -350,7 +350,7 @@ class ConfigWidget(ConfigWidgetBase, Ui_Form):
         r('book_list_tooltips', gprefs)
         r('show_layout_buttons', gprefs, restart_required=True)
         r('row_numbers_in_book_list', gprefs)
-        r('tag_browser_old_look', gprefs, restart_required=True)
+        r('tag_browser_old_look', gprefs)
         r('tag_browser_hide_empty_categories', gprefs)
         r('bd_show_cover', gprefs)
         r('bd_overlay_cover_size', gprefs)
@@ -361,6 +361,7 @@ class ConfigWidget(ConfigWidgetBase, Ui_Form):
         r('cover_grid_spacing', gprefs)
         r('cover_grid_show_title', gprefs)
         r('tag_browser_show_counts', gprefs)
+        r('tag_browser_item_padding', gprefs)
 
         r('cover_flow_queue_length', config, restart_required=True)
         r('cover_browser_reflections', gprefs)
@@ -707,6 +708,7 @@ class ConfigWidget(ConfigWidgetBase, Ui_Form):
         m = gui.library_view.model()
         m.beginResetModel(), m.endResetModel()
         self.update_font_display()
+        gui.tags_view.set_look_and_feel()
         gui.tags_view.reread_collapse_parameters()
         gui.library_view.refresh_book_details()
         gui.library_view.set_row_header_visibility()

src/calibre/gui2/preferences/look_feel.ui

@@ -839,7 +839,7 @@ A value of zero means calculate automatically.</string>
        <property name="fieldGrowthPolicy">
         <enum>QFormLayout::ExpandingFieldsGrow</enum>
        </property>
-       <item row="2" column="0">
+       <item row="3" column="0">
         <widget class="QLabel" name="label_10">
          <property name="text">
           <string>Co&amp;llapse when more items than:</string>
@@ -849,7 +849,7 @@ A value of zero means calculate automatically.</string>
          </property>
         </widget>
        </item>
-       <item row="2" column="1">
+       <item row="3" column="1">
         <widget class="QSpinBox" name="opt_tags_browser_collapse_at">
          <property name="toolTip">
           <string>If a Tag browser category has more than this number of items, it is divided
@@ -860,7 +860,7 @@ up into subcategories. If the partition method is set to disable, this value is
          </property>
         </widget>
        </item>
-       <item row="3" column="0">
+       <item row="5" column="0">
         <widget class="QLabel" name="label_8111">
          <property name="text">
           <string>Categories &amp;not to partition:</string>
@@ -870,7 +870,7 @@ up into subcategories. If the partition method is set to disable, this value is
          </property>
         </widget>
        </item>
-       <item row="3" column="1">
+       <item row="5" column="1">
         <widget class="EditWithComplete" name="opt_tag_browser_dont_collapse">
          <property name="sizePolicy">
           <sizepolicy hsizetype="Expanding" vsizetype="Fixed">
@@ -887,7 +887,7 @@ a few top-level elements.</string>
          </property>
         </widget>
        </item>
-       <item row="5" column="0">
+       <item row="7" column="0">
         <widget class="QLabel" name="label_81">
          <property name="text">
           <string>Categories with &amp;hierarchical items:</string>
@@ -897,7 +897,7 @@ a few top-level elements.</string>
          </property>
         </widget>
        </item>
-       <item row="5" column="1">
+       <item row="7" column="1">
         <widget class="EditWithComplete" name="opt_categories_using_hierarchy">
          <property name="sizePolicy">
           <sizepolicy hsizetype="Expanding" vsizetype="Fixed">
@@ -915,14 +915,14 @@ then the tags will be displayed each on their own line.</string>
          </property>
         </widget>
        </item>
-       <item row="8" column="0" colspan="2">
+       <item row="10" column="0" colspan="2">
         <widget class="QCheckBox" name="opt_tag_browser_old_look">
          <property name="text">
           <string>Use &amp;alternating row colors in the Tag browser</string>
          </property>
         </widget>
        </item>
-       <item row="9" column="0" colspan="2">
+       <item row="11" column="0" colspan="2">
         <widget class="QCheckBox" name="opt_tag_browser_hide_empty_categories">
          <property name="toolTip">
           <string>When checked, calibre will automatically hide any category
@@ -956,7 +956,7 @@ if you never want subcategories</string>
          </property>
         </widget>
        </item>
-       <item row="6" column="0">
+       <item row="8" column="0">
         <widget class="QCheckBox" name="opt_show_avg_rating">
          <property name="text">
           <string>Show &amp;average ratings in the Tag browser</string>
@@ -966,7 +966,7 @@ if you never want subcategories</string>
          </property>
         </widget>
        </item>
-       <item row="7" column="0" colspan="2">
+       <item row="9" column="0" colspan="2">
         <widget class="QCheckBox" name="opt_tag_browser_show_counts">
          <property name="toolTip">
           <string>Show counts for items in the Tag browser. Such as the number of books
@@ -978,6 +978,38 @@ see the counts by hovering your mouse over any item.</string>
          </property>
         </widget>
        </item>
+       <item row="4" column="0">
+        <widget class="QLabel" name="label">
+         <property name="text">
+          <string>&amp;Padding between items:</string>
+         </property>
+         <property name="buddy">
+          <cstring>opt_tag_browser_item_padding</cstring>
+         </property>
+        </widget>
+       </item>
+       <item row="4" column="1">
+        <widget class="QDoubleSpinBox" name="opt_tag_browser_item_padding">
+         <property name="toolTip">
+          <string>The spacing between consecutive items in the Tag browser. In units of (ex) which is the approximate height of the letter 'x' in the currently used font. </string>
+         </property>
+         <property name="suffix">
+          <string> ex</string>
+         </property>
+         <property name="decimals">
+          <number>1</number>
+         </property>
+         <property name="minimum">
+          <double>-1.000000000000000</double>
+         </property>
+         <property name="maximum">
+          <double>2.000000000000000</double>
+         </property>
+         <property name="singleStep">
+          <double>0.100000000000000</double>
+         </property>
+        </widget>
+       </item>
       </layout>
      </widget>
      <widget class="QWidget" name="cover_browser_tab">

src/calibre/gui2/tag_browser/view.py

@@ -30,7 +30,7 @@ class TagDelegate(QStyledItemDelegate):  # {{{
 
     def __init__(self, *args, **kwargs):
         QStyledItemDelegate.__init__(self, *args, **kwargs)
-        self.old_look = gprefs['tag_browser_old_look']
+        self.old_look = False
         self.rating_pat = re.compile(r'[%s]' % rating_to_stars(3, True))
         self.rating_font = QFont(rating_font())
 
@@ -162,6 +162,12 @@ class TagsView(QTreeView):  # {{{
         self._model.user_categories_edited.connect(self.user_categories_edited,
                 type=Qt.QueuedConnection)
         self._model.drag_drop_finished.connect(self.drag_drop_finished)
+        self.set_look_and_feel()
+        # Allowing keyboard focus looks bad in the Qt Fusion style and is useless
+        # anyway since the enter/spacebar keys do nothing
+        self.setFocusPolicy(Qt.NoFocus)
+
+    def set_look_and_feel(self):
         stylish_tb = '''
                 QTreeView {
                     background-color: palette(window);
@@ -172,8 +178,8 @@ class TagsView(QTreeView):  # {{{
         self.setStyleSheet('''
                 QTreeView::item {
                     border: 1px solid transparent;
-                    padding-top:0.8ex;
+                    padding-top:PADex;
-                    padding-bottom:0.8ex;
+                    padding-bottom:PADex;
                 }
 
                 QTreeView::item:hover {
@@ -181,12 +187,10 @@ class TagsView(QTreeView):  # {{{
                     border: 1px solid #bfcde4;
                     border-radius: 6px;
                 }
-        ''' + ('' if gprefs['tag_browser_old_look'] else stylish_tb))
+        '''.replace('PAD', str(gprefs['tag_browser_item_padding'])) + (
-        if gprefs['tag_browser_old_look']:
+            '' if gprefs['tag_browser_old_look'] else stylish_tb))
-            self.setAlternatingRowColors(True)
+        self.setAlternatingRowColors(gprefs['tag_browser_old_look'])
-        # Allowing keyboard focus looks bad in the Qt Fusion style and is useless
+        self.itemDelegate().old_look = gprefs['tag_browser_old_look']
-        # anyway since the enter/spacebar keys do nothing
-        self.setFocusPolicy(Qt.NoFocus)
 
     @property
     def hidden_categories(self):