Cleanup previous PR

- Improve rendering of splitter handle using fewer, closer spaced,
  circular dots

- Fix book details splitter not being rendered correctly on first start
  when there is no saved state to restore

- Remove geometry save/restore of splitter as this is handled by
  restore_state

- Remove call to setChildrenCollapsible before any children were added,
  causing Qt to print an error to stderr

Fixes #1994065 [Enhancement Request: Details pane: Splitter between cover and details](https://bugs.launchpad.net/calibre/+bug/1994065)

src/calibre/gui2/book_details.py

@@ -10,7 +10,7 @@ from qt.core import (
     QAction, QApplication, QClipboard, QColor, QDialog, QEasingCurve, QIcon,
     QKeySequence, QMenu, QMimeData, QPainter, QPen, QPixmap,
     QPropertyAnimation, QRect, QSize, QSizePolicy, Qt, QUrl, QWidget, pyqtProperty,
-    QTimer, pyqtSignal
+    pyqtSignal
 )
 
 from calibre import fit_image, sanitize_file_name
@@ -920,13 +920,9 @@ class DetailsLayout(BasicSplitter):  # {{{
         orientation = Qt.Orientation.Vertical if vertical else Qt.Orientation.Horizontal
         BasicSplitter.__init__(self, orientation, parent)
         self.vertical = vertical
-        self.setCollapsible(0, True)
-
         self._children = []
-
         self.min_size = QSize(190, 200) if vertical else QSize(120, 120)
         self.setContentsMargins(0, 0, 0, 0)
-        self.restore_geometry(gprefs, 'book_details_splitter')
         self.splitterMoved.connect(self.do_splitter_moved)
 
     def minimumSize(self):
@@ -945,14 +941,16 @@ class DetailsLayout(BasicSplitter):  # {{{
 
     def restore_splitter_state(self):
         s = gprefs.get('book_details_widget_splitter_state')
-        if s is not None:
+        if s is None:
+            # Without this on first start the splitter is rendered over the cover
+            self.setSizes([20, 80])
+        else:
             self.restoreState(s)
         self.setOrientation(Qt.Orientation.Vertical if self.vertical else Qt.Orientation.Horizontal)
 
     def setGeometry(self, r):
-        BasicSplitter.setGeometry(self, r)
+        super().setGeometry(r)
         self.do_layout(r)
-        self.restore_splitter_state()
 
     def do_splitter_moved(self, *args):
         gprefs['book_details_widget_splitter_state'] = bytearray(self.saveState())
@@ -1004,8 +1002,7 @@ class DetailsLayout(BasicSplitter):  # {{{
             cover.setGeometry(QRect(x, y, cw, r.height()))
             x += cw + 5
             details.setGeometry(QRect(x, y, r.width() - cw - 5, r.height()))
-        self.restore_splitter_state() # only required on first call to do_layout, but ...
-        self.save_geometry(gprefs, 'book_details_splitter')
+        self.restore_splitter_state()  # only required on first call to do_layout, but ...
         cover.do_layout()
 # }}}
 

src/calibre/gui2/init.py

@@ -8,7 +8,7 @@ __docformat__ = 'restructuredtext en'
 import functools
 from qt.core import (
     QAction, QApplication, QDialog, QEvent, QIcon, QLabel, QMenu, QPixmap, QUrl,
-    QSizePolicy, QSplitter, QStackedWidget, QStatusBar, QStyle, QStyleOption,
+    QSizePolicy, QStackedWidget, QStatusBar, QStyle, QStyleOption,
     QStylePainter, Qt, QTabBar, QTimer, QToolButton, QVBoxLayout, QWidget
 )
 

src/calibre/gui2/widgets.py

@@ -982,10 +982,6 @@ class PythonHighlighter(QSyntaxHighlighter):  # {{{
 
 class BasicSplitterHandle(QSplitterHandle):
 
-    def __init__(self, orientation, splitter):
-        QSplitterHandle.__init__(self, orientation, splitter)
-        self.handle_width = splitter.handleWidth()
-
     def paintEvent(self, event):
         rect = event.rect()
         painter = QPainter(self)
@@ -997,16 +993,18 @@ class BasicSplitterHandle(QSplitterHandle):
         # draw the dots
         painter.setBrush(palette.color(QPalette.ColorGroup.Normal, QPalette.ColorRole.Shadow))
         horizontal = self.orientation() == Qt.Orientation.Horizontal
-        dot_count = 6
-        dot_size = int(max(1, self.handle_width/2))
+        dot_count = 4
+        cr = self.contentsRect()
+        handle_width = cr.width() if horizontal else cr.height()
+        dot_size = int(max(1, handle_width))
         start_point = max(0, int((rect.height()/2 if horizontal else rect.width()/2) - (dot_count*dot_size/2)))
         for i in range(dot_count):
-            # Move the rect to leave 2 dot spaces between the dots
+            # Move the rect to leave spaces between the dots
             if horizontal:
-                dot_rect = QRect(1, start_point + i*dot_size*3, dot_size, dot_size)
+                dot_rect = QRect(0, start_point + i*dot_size*2, dot_size, dot_size)
             else:
-                dot_rect = QRect(start_point + i*dot_size*3, 1, dot_size, dot_size)
-            painter.drawRect(dot_rect)
+                dot_rect = QRect(start_point + i*dot_size*2, 0, dot_size, dot_size)
+            painter.drawEllipse(dot_rect)
         painter.end()