Get rid of BasicSplitter

Move custom drawing of splitter handle into the style where it belongs.
This means all splitters now use the custom handle without needing to
sprinkle a special class everywhere.

Note that this only works when using the calibre style not the system
one. This is by design, since we do not want to override drawing of
"system" components.

src/calibre/gui2/book_details.py

@@ -8,7 +8,7 @@ from collections import namedtuple
 from functools import partial
 from qt.core import (
     QAction, QApplication, QClipboard, QColor, QDialog, QEasingCurve, QIcon,
-    QKeySequence, QMenu, QMimeData, QPainter, QPen, QPixmap,
+    QKeySequence, QMenu, QMimeData, QPainter, QPen, QPixmap, QSplitter,
     QPropertyAnimation, QRect, QSize, QSizePolicy, Qt, QUrl, QWidget, pyqtProperty,
     pyqtSignal
 )
@@ -30,7 +30,6 @@ from calibre.gui2.dialogs.confirm_delete import confirm, confirm as confirm_dele
 from calibre.gui2.dnd import (
     dnd_get_files, dnd_get_image, dnd_has_extension, dnd_has_image, image_extensions
 )
-from calibre.gui2.widgets import BasicSplitter
 from calibre.gui2.widgets2 import HTMLDisplay
 from calibre.utils.config import tweaks
 from calibre.utils.img import blend_image, image_from_x
@@ -914,11 +913,11 @@ class BookInfo(HTMLDisplay):
 # }}}
 
 
-class DetailsLayout(BasicSplitter):  # {{{
+class DetailsLayout(QSplitter):  # {{{
 
     def __init__(self, vertical, parent):
         orientation = Qt.Orientation.Vertical if vertical else Qt.Orientation.Horizontal
-        BasicSplitter.__init__(self, orientation, parent)
+        super().__init__(orientation, parent)
         self.vertical = vertical
         self._children = []
         self.min_size = QSize(190, 200) if vertical else QSize(120, 120)

src/calibre/gui2/dialogs/book_info.py

@@ -7,7 +7,7 @@ from qt.core import (
     QAction, QApplication, QBrush, QCheckBox, QDialog, QGridLayout,
     QHBoxLayout, QIcon, QKeySequence, QLabel, QListView, QModelIndex, QPalette,
     QPixmap, QPushButton, QShortcut, QSize, Qt, QTimer, QToolButton,
-    QVBoxLayout, QWidget, pyqtSignal, QDialogButtonBox
+    QVBoxLayout, QWidget, pyqtSignal, QDialogButtonBox, QSplitter
 )
 
 from calibre import fit_image
@@ -17,7 +17,7 @@ from calibre.gui2.book_details import (
     set_html
 )
 from calibre.gui2.ui import get_gui
-from calibre.gui2.widgets import CoverView, BasicSplitter
+from calibre.gui2.widgets import CoverView
 from calibre.gui2.widgets2 import Dialog, HTMLDisplay
 
 
@@ -136,7 +136,7 @@ class BookInfo(QDialog):
         QDialog.__init__(self, parent)
         self.marked = None
         self.gui = parent
-        self.splitter = BasicSplitter(self)
+        self.splitter = QSplitter(self)
         self._l = l = QVBoxLayout(self)
         self.setLayout(l)
         l.addWidget(self.splitter)

src/calibre/gui2/dialogs/check_library.py

@@ -11,13 +11,12 @@ from qt.core import (
     QApplication, QCheckBox, QCursor, QDialog, QDialogButtonBox, QGridLayout,
     QHBoxLayout, QIcon, QLabel, QLineEdit, QProgressBar, QPushButton,
     QStackedLayout, Qt, QTextEdit, QTreeWidget, QTreeWidgetItem, QVBoxLayout,
-    QWidget, pyqtSignal
+    QWidget, pyqtSignal, QSplitter
 )
 from threading import Thread
 
 from calibre import as_unicode, prints
 from calibre.gui2.dialogs.confirm_delete import confirm
-from calibre.gui2.widgets import BasicSplitter
 from calibre.library.check_library import CHECKS, CheckLibrary
 from calibre.utils.recycle_bin import delete_file, delete_tree
 
@@ -126,7 +125,7 @@ class CheckLibraryDialog(QDialog):
 
         self._tl = QHBoxLayout()
         self.setLayout(self._tl)
-        self.splitter = BasicSplitter(self)
+        self.splitter = QSplitter(self)
         self.left = QWidget(self)
         self.splitter.addWidget(self.left)
         self.helpw = QTextEdit(self)

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, QStackedWidget, QStatusBar, QStyle, QStyleOption,
+    QSizePolicy, QStackedWidget, QStatusBar, QStyle, QStyleOption, QSplitter,
     QStylePainter, Qt, QTabBar, QTimer, QToolButton, QVBoxLayout, QWidget
 )
 
@@ -23,7 +23,7 @@ from calibre.gui2.library.alternate_views import GridView
 from calibre.gui2.library.views import BooksView, DeviceBooksView
 from calibre.gui2.notify import get_notifier
 from calibre.gui2.tag_browser.ui import TagBrowserWidget
-from calibre.gui2.widgets import LayoutButton, Splitter, BasicSplitter
+from calibre.gui2.widgets import LayoutButton, Splitter
 from calibre.utils.config import prefs
 from calibre.utils.icu import sort_key
 from calibre.utils.localization import localize_website_link
@@ -112,10 +112,10 @@ class LibraryViewMixin:  # {{{
     # }}}
 
 
-class QuickviewSplitter(BasicSplitter):  # {{{
+class QuickviewSplitter(QSplitter):  # {{{
 
     def __init__(self, parent=None, orientation=Qt.Orientation.Vertical, qv_widget=None):
-        BasicSplitter.__init__(self, parent=parent, orientation=orientation)
+        super().__init__(parent=parent, orientation=orientation)
         self.splitterMoved.connect(self.splitter_moved)
         self.setChildrenCollapsible(False)
         self.qv_widget = qv_widget
@@ -124,7 +124,7 @@ class QuickviewSplitter(BasicSplitter):  # {{{
         gprefs['quickview_dialog_heights'] = self.sizes()
 
     def resizeEvent(self, *args):
-        BasicSplitter.resizeEvent(self, *args)
+        super().resizeEvent(*args)
         if self.sizes()[1] != 0:
             gprefs['quickview_dialog_heights'] = self.sizes()
 

src/calibre/gui2/metadata/single.py

@@ -12,8 +12,8 @@ from functools import partial
 from qt.core import (
     QDialog, QDialogButtonBox, QFrame, QGridLayout, QGroupBox, QHBoxLayout, QIcon,
     QInputDialog, QKeySequence, QMenu, QPushButton, QScrollArea, QShortcut, QSize,
-    QSizePolicy, QSpacerItem, Qt, QTabWidget, QToolButton, QVBoxLayout,
-    QWidget, pyqtSignal
+    QSizePolicy, QSpacerItem, QSplitter, Qt, QTabWidget, QToolButton, QVBoxLayout,
+    QWidget, pyqtSignal,
 )
 
 from calibre.constants import ismacos
@@ -26,10 +26,9 @@ from calibre.gui2.metadata.basic_widgets import (
     AuthorsEdit, AuthorSortEdit, BuddyLabel, CommentsEdit, Cover, DateEdit,
     FormatsManager, IdentifiersEdit, LanguagesEdit, PubdateEdit, PublisherEdit,
     RatingEdit, RightClickButton, SeriesEdit, SeriesIndexEdit, TagsEdit, TitleEdit,
-    TitleSortEdit, show_locked_file_error
+    TitleSortEdit, show_locked_file_error,
 )
 from calibre.gui2.metadata.single_download import FullFetch
-from calibre.gui2.widgets import BasicSplitter
 from calibre.gui2.widgets2 import CenteredToolButton
 from calibre.library.comments import merge_comments as merge_two_comments
 from calibre.utils.date import local_tz
@@ -732,13 +731,13 @@ class MetadataSingleDialogBase(QDialog):
     # }}}
 
 
-class Splitter(BasicSplitter):
+class Splitter(QSplitter):
 
     frame_resized = pyqtSignal(object)
 
     def resizeEvent(self, ev):
         self.frame_resized.emit(ev)
-        return BasicSplitter.resizeEvent(self, ev)
+        return super().resizeEvent(ev)
 
 
 class MetadataSingleDialog(MetadataSingleDialogBase):  # {{{
@@ -1040,7 +1039,7 @@ class MetadataSingleDialogAlt1(MetadataSingleDialogBase):  # {{{
             QSizePolicy.Policy.Expanding))
         wgl.addWidget(self.formats_manager)
 
-        self.splitter = BasicSplitter(Qt.Orientation.Horizontal, tab1)
+        self.splitter = Splitter(Qt.Orientation.Horizontal, tab1)
         tab1.l.addWidget(self.splitter)
         self.splitter.addWidget(self.cover)
         self.splitter.addWidget(wsp)
@@ -1208,7 +1207,7 @@ class MetadataSingleDialogAlt2(MetadataSingleDialogBase):  # {{{
         cover_layout.addLayout(hl)
         sto(self.cover.buttons[-2], self.cover.buttons[-1])
         # Splitter for both cover & formats boxes
-        self.cover_and_formats = cover_and_formats = BasicSplitter(Qt.Orientation.Vertical)
+        self.cover_and_formats = cover_and_formats = Splitter(Qt.Orientation.Vertical)
         # Put a very small margin on the left so that the word "Cover" doesn't
         # touch the splitter
         cover_and_formats.setContentsMargins(1, 0, 0, 0)

src/calibre/gui2/metadata/single_download.py

@@ -17,7 +17,7 @@ from qt.core import (
     QStyledItemDelegate, QTextDocument, QRectF, QIcon, Qt, QApplication,
     QDialog, QVBoxLayout, QLabel, QDialogButtonBox, QStyle, QStackedWidget,
     QWidget, QTableView, QGridLayout, QPalette, QTimer, pyqtSignal,
-    QAbstractTableModel, QSize, QListView, QPixmap, QModelIndex,
+    QAbstractTableModel, QSize, QListView, QPixmap, QModelIndex, QSplitter,
     QAbstractListModel, QRect, QTextBrowser, QStringListModel, QMenu, QItemSelectionModel,
     QCursor, QHBoxLayout, QPushButton, QSizePolicy, QAbstractItemView)
 
@@ -29,7 +29,6 @@ from calibre.ebooks.metadata.book.base import Metadata
 from calibre.ebooks.metadata.opf2 import OPF
 from calibre.gui2 import error_dialog, rating_font, gprefs
 from calibre.gui2.progress_indicator import SpinAnimator
-from calibre.gui2.widgets import BasicSplitter
 from calibre.gui2.widgets2 import HTMLDisplay
 from calibre.utils.date import (utcnow, fromordinal, format_date,
         UNDEFINED_DATE, as_utc)
@@ -446,7 +445,7 @@ class IdentifyWidget(QWidget):  # {{{
         self.top.setWordWrap(True)
         l.addWidget(self.top)
 
-        self.splitter = s = BasicSplitter(self)
+        self.splitter = s = QSplitter(self)
         s.setChildrenCollapsible(False)
         l.addWidget(s, 100)
         self.results_view = ResultsView(self)

src/calibre/gui2/pin_columns.py

@@ -2,11 +2,10 @@
 # License: GPLv3 Copyright: 2018, Kovid Goyal <kovid at kovidgoyal.net>
 
 
-from qt.core import QTableView
+from qt.core import QTableView, QSplitter
 
 from calibre.gui2.library import DEFAULT_SORT
 from calibre.gui2 import gprefs
-from calibre.gui2.widgets import BasicSplitter
 
 
 class PinTableView(QTableView):
@@ -125,10 +124,10 @@ class PinTableView(QTableView):
                 self.apply_state(state)
 
 
-class PinContainer(BasicSplitter):
+class PinContainer(QSplitter):
 
     def __init__(self, books_view, parent=None):
-        BasicSplitter.__init__(self, parent)
+        super().__init__(parent)
         self.setChildrenCollapsible(False)
         self.books_view = books_view
         self.addWidget(books_view)

src/calibre/gui2/preferences/tweaks.py

@@ -11,7 +11,7 @@ from calibre import isbytestring, prepare_string_for_xml
 from calibre.gui2 import error_dialog, info_dialog
 from calibre.gui2.preferences import AbortCommit, ConfigWidgetBase, test_widget
 from calibre.gui2.search_box import SearchBox2
-from calibre.gui2.widgets import PythonHighlighter, BasicSplitter
+from calibre.gui2.widgets import PythonHighlighter
 from calibre.utils.config_base import (default_tweaks_raw, exec_tweaks,
                                        normalize_tweak, read_custom_tweaks,
                                        write_custom_tweaks)
@@ -22,7 +22,7 @@ from qt.core import (QAbstractItemView, QAbstractListModel, QApplication,
                      QComboBox, QDialog, QDialogButtonBox, QFont, QGridLayout,
                      QGroupBox, QIcon, QItemSelectionModel, QLabel, QListView,
                      QMenu, QModelIndex, QPlainTextEdit, QPushButton,
-                     QSizePolicy, Qt, QVBoxLayout, QWidget,
+                     QSizePolicy, Qt, QVBoxLayout, QWidget, QSplitter,
                      pyqtSignal)
 
 ROOT = QModelIndex()
@@ -371,7 +371,7 @@ class ConfigWidget(ConfigWidgetBase):
             _("Values for the tweaks are shown below. Edit them to change the behavior of calibre."
               " Your changes will only take effect <b>after a restart</b> of calibre."))
         l.addWidget(la), la.setWordWrap(True)
-        self.splitter = s = BasicSplitter(self)
+        self.splitter = s = QSplitter(self)
         s.setChildrenCollapsible(False)
         l.addWidget(s, 10)
 

src/calibre/gui2/progress_indicator/QProgressIndicator.cpp

@@ -336,6 +336,29 @@ void CalibreStyle::drawPrimitive(PrimitiveElement element, const QStyleOption *
 void CalibreStyle::drawControl(ControlElement element, const QStyleOption *option, QPainter *painter, const QWidget *widget) const {
     const QStyleOptionViewItem *vopt = NULL;
     switch(element) {
+        case CE_Splitter: {
+            painter->save();
+            // draw the separator bar.
+            painter->setPen(Qt::PenStyle::NoPen);
+            painter->setBrush(option->palette.color(QPalette::ColorGroup::Normal, QPalette::ColorRole::AlternateBase));
+            painter->drawRect(option->rect);
+            // draw the dots
+            painter->setBrush(option->palette.color(QPalette::ColorGroup::Normal, QPalette::ColorRole::Shadow));
+            bool horizontal = option->state & QStyle::State_Horizontal ? true : false;
+            static const int dot_count = 4;
+            int handle_width = horizontal ? option->rect.width() : option->rect.height();
+            int dot_size = std::max(1, handle_width);
+            int start_point = (horizontal ? option->rect.height()/2 : option->rect.width()/2) - (dot_count*dot_size/2);
+            QRect dot_rect;
+            for (int i = 0; i < dot_count; i++) {
+                // Move the rect to leave spaces between the dots
+                if (horizontal) dot_rect = QRect(0, start_point + i*dot_size*2, dot_size, dot_size);
+                else dot_rect = QRect(start_point + i*dot_size*2, 0, dot_size, dot_size);
+                painter->drawEllipse(dot_rect);
+            }
+            painter->restore();
+            return;
+        } break;
         case CE_ItemViewItem: {
             if (option->state & QStyle::State_HasFocus && (vopt = qstyleoption_cast<const QStyleOptionViewItem *>(option)) && widget && widget->property("highlight_current_item").toBool()) {
                 if (is_color_dark(option->palette.color(QPalette::Window))) {

src/calibre/gui2/widgets.py

@@ -980,46 +980,12 @@ class PythonHighlighter(QSyntaxHighlighter):  # {{{
 
 # Splitter {{{
 
-class BasicSplitterHandle(QSplitterHandle):
-
-    def paintEvent(self, event):
-        rect = event.rect()
-        painter = QPainter(self)
-        # draw the separator bar.
-        painter.setPen(Qt.NoPen)
-        palette = QApplication.palette()
-        painter.setBrush(palette.color(QPalette.ColorGroup.Normal, QPalette.ColorRole.AlternateBase))
-        painter.drawRect(rect)
-        # draw the dots
-        painter.setBrush(palette.color(QPalette.ColorGroup.Normal, QPalette.ColorRole.Shadow))
-        horizontal = self.orientation() == Qt.Orientation.Horizontal
-        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 spaces between the dots
-            if horizontal:
-                dot_rect = QRect(0, start_point + i*dot_size*2, dot_size, dot_size)
-            else:
-                dot_rect = QRect(start_point + i*dot_size*2, 0, dot_size, dot_size)
-            painter.drawEllipse(dot_rect)
-        painter.end()
-
-
-class BasicSplitter(QSplitter):
-
-    def createHandle(self):
-        return BasicSplitterHandle(self.orientation(), self)
-
-
-class SplitterHandle(BasicSplitterHandle):
+class SplitterHandle(QSplitterHandle):
 
     double_clicked = pyqtSignal(object)
 
     def __init__(self, orientation, splitter):
-        BasicSplitterHandle.__init__(self, orientation, splitter)
+        super().__init__(orientation, splitter)
         splitter.splitterMoved.connect(self.splitter_moved,
                 type=Qt.ConnectionType.QueuedConnection)
         self.double_clicked.connect(splitter.double_clicked,
@@ -1099,7 +1065,7 @@ class LayoutButton(QToolButton):
         return QToolButton.mouseReleaseEvent(self, ev)
 
 
-class Splitter(BasicSplitter):
+class Splitter(QSplitter):
 
     state_changed = pyqtSignal(object)
     reapply_sizes = pyqtSignal(object)
@@ -1108,7 +1074,7 @@ class Splitter(BasicSplitter):
             initial_side_size=120, connect_button=True,
             orientation=Qt.Orientation.Horizontal, side_index=0, parent=None,
             shortcut=None, hide_handle_on_single_panel=True):
-        BasicSplitter.__init__(self, parent)
+        super().__init__(parent)
         self.reapply_sizes.connect(self.setSizes, type=Qt.ConnectionType.QueuedConnection)
         self.hide_handle_on_single_panel = hide_handle_on_single_panel
         if hide_handle_on_single_panel:
@@ -1222,7 +1188,7 @@ class Splitter(BasicSplitter):
 
     def do_resize(self, *args):
         orig = self.desired_side_size
-        BasicSplitter.resizeEvent(self, self._resize_ev)
+        super().resizeEvent(self._resize_ev)
         if orig > 20 and self.desired_show:
             c = 0
             while abs(self.side_index_size - orig) > 10 and c < 5: