Use an icon rather than a color to report errors in line edits. Fixes #2003652 [color frame in edit metadata](https://bugs.launchpad.net/calibre/+bug/2003652)

src/calibre/gui2/__init__.py

@@ -1291,10 +1291,6 @@ class Application(QApplication):
         ans.setDevicePixelRatio(device_pixel_ratio)
         return ans
 
-    def stylesheet_for_line_edit(self, is_error=False):
-        col = '#FF2400' if is_error else '#50c878'
-        return f'QLineEdit {{ border: 2px solid {col}; border-radius: 3px }}'
-
     def _send_file_open_events(self):
         with self._file_open_lock:
             if self._file_open_paths:

src/calibre/gui2/dialogs/metadata_bulk.py

@@ -7,9 +7,8 @@ import regex
 from collections import defaultdict, namedtuple
 from io import BytesIO
 from qt.core import (
-    QApplication, QComboBox, QCompleter, QDateTime, QDialog, QDialogButtonBox, QFont,
-    QGridLayout, QInputDialog, QLabel, QLineEdit, QProgressBar, QSize, Qt, QVBoxLayout,
-    pyqtSignal,
+    QComboBox, QCompleter, QDateTime, QDialog, QDialogButtonBox, QFont, QGridLayout,
+    QInputDialog, QLabel, QLineEdit, QProgressBar, QSize, Qt, QVBoxLayout, pyqtSignal,
 )
 from threading import Thread
 
@@ -27,7 +26,9 @@ from calibre.gui2.custom_column_widgets import populate_metadata_page
 from calibre.gui2.dialogs.metadata_bulk_ui import Ui_MetadataBulkDialog
 from calibre.gui2.dialogs.tag_editor import TagEditor
 from calibre.gui2.dialogs.template_line_editor import TemplateLineEditor
-from calibre.gui2.widgets import LineEditECM
+from calibre.gui2.widgets import (
+    LineEditECM, setup_status_actions, update_status_actions,
+)
 from calibre.startup import connect_lambda
 from calibre.utils.config import JSONConfig, dynamic, prefs, tweaks
 from calibre.utils.date import internal_iso_format_string, qt_to_dt
@@ -499,6 +500,7 @@ class MetadataBulkDialog(QDialog, Ui_MetadataBulkDialog):
     def __init__(self, window, rows, model, tab, refresh_books):
         QDialog.__init__(self, window)
         self.setupUi(self)
+        setup_status_actions(self.test_result)
         self.series.set_sort_func(title_sort)
         self.model = model
         self.db = model.db
@@ -899,10 +901,11 @@ class MetadataBulkDialog(QDialog, Ui_MetadataBulkDialog):
         self.s_r_search_field_changed(self.search_field.currentIndex())
 
     def s_r_set_colors(self):
+        tt = ''
         if self.s_r_error is not None:
-            self.test_result.setText(error_message(self.s_r_error))
-        self.test_result.setStyleSheet(
-                QApplication.instance().stylesheet_for_line_edit(self.s_r_error is not None))
+            tt = error_message(self.s_r_error)
+            self.test_result.setText(tt)
+        update_status_actions(self.test_result, self.s_r_error is None, tt)
         for i in range(0,self.s_r_number_of_books):
             getattr(self, 'book_%d_result'%(i+1)).setText('')
 

src/calibre/gui2/metadata/basic_widgets.py

@@ -37,7 +37,7 @@ from calibre.gui2.comments_editor import Editor
 from calibre.gui2.complete2 import EditWithComplete
 from calibre.gui2.dialogs.tag_editor import TagEditor
 from calibre.gui2.languages import LanguagesEdit as LE
-from calibre.gui2.widgets import EnLineEdit, FormatList as _FormatList, ImageView
+from calibre.gui2.widgets import EnLineEdit, FormatList as _FormatList, ImageView, LineEditIndicators
 from calibre.gui2.widgets2 import (
     DateTimeEdit, Dialog, RatingEditor, RightClickButton, access_key,
     populate_standard_spinbox_context_menu,
@@ -261,7 +261,7 @@ class TitleEdit(EnLineEdit, ToMetadataMixin):
         self.dialog = None
 
 
-class TitleSortEdit(TitleEdit, ToMetadataMixin):
+class TitleSortEdit(TitleEdit, ToMetadataMixin, LineEditIndicators):
 
     TITLE_ATTR = FIELD_NAME = 'title_sort'
     TOOLTIP = _('Specify how this book should be sorted when by title.'
@@ -270,15 +270,16 @@ class TitleSortEdit(TitleEdit, ToMetadataMixin):
 
     def __init__(self, parent, title_edit, autogen_button, languages_edit):
         TitleEdit.__init__(self, parent)
+        self.setup_status_actions()
         self.title_edit = title_edit
         self.languages_edit = languages_edit
 
         base = self.TOOLTIP
         ok_tooltip = '<p>' + textwrap.fill(base+'<br><br>' + _(
-            ' The green color indicates that the current '
+            ' The ok icon indicates that the current '
             'title sort matches the current title'))
         bad_tooltip = '<p>'+textwrap.fill(base + '<br><br>' + _(
-            ' The red color warns that the current '
+            ' The error icon warns that the current '
             'title sort does not match the current title. '
             'No action is required if this is what you want.'))
         self.tooltips = (ok_tooltip, bad_tooltip)
@@ -314,8 +315,8 @@ class TitleSortEdit(TitleEdit, ToMetadataMixin):
     def update_state(self, *args):
         ts = title_sort(self.title_edit.current_val, lang=self.book_lang)
         normal = ts == self.current_val
-        self.setStyleSheet(QApplication.instance().stylesheet_for_line_edit(not normal))
         tt = self.tooltips[0 if normal else 1]
+        self.update_status_actions(normal, tt)
         self.setToolTip(tt)
         self.setWhatsThis(tt)
 
@@ -456,7 +457,7 @@ class AuthorsEdit(EditWithComplete, ToMetadataMixin):
             pass
 
 
-class AuthorSortEdit(EnLineEdit, ToMetadataMixin):
+class AuthorSortEdit(EnLineEdit, ToMetadataMixin, LineEditIndicators):
 
     TOOLTIP = _('Specify how the author(s) of this book should be sorted. '
             'For example Charles Dickens should be sorted as Dickens, '
@@ -470,15 +471,16 @@ class AuthorSortEdit(EnLineEdit, ToMetadataMixin):
     def __init__(self, parent, authors_edit, autogen_button, db,
             copy_a_to_as_action, copy_as_to_a_action, a_to_as, as_to_a):
         EnLineEdit.__init__(self, parent)
+        self.setup_status_actions()
         self.authors_edit = authors_edit
         self.db = db
 
         base = self.TOOLTIP
         ok_tooltip = '<p>' + textwrap.fill(base+'<br><br>' + _(
-            ' The green color indicates that the current '
+            ' The ok icon indicates that the current '
             'author sort matches the current author'))
         bad_tooltip = '<p>'+textwrap.fill(base + '<br><br>'+ _(
-            ' The red color indicates that the current '
+            ' The error icon indicates that the current '
             'author sort does not match the current author. '
             'No action is required if this is what you want.'))
         self.tooltips = (ok_tooltip, bad_tooltip)
@@ -529,8 +531,8 @@ class AuthorSortEdit(EnLineEdit, ToMetadataMixin):
         au = self.author_sort_from_authors(string_to_authors(au))
 
         normal = au == self.current_val
-        self.setStyleSheet(QApplication.instance().stylesheet_for_line_edit(not normal))
         tt = self.tooltips[0 if normal else 1]
+        self.update_status_actions(normal, tt)
         self.setToolTip(tt)
         self.setWhatsThis(tt)
 
@@ -1572,7 +1574,7 @@ class Identifiers(Dialog):
         Dialog.accept(self)
 
 
-class IdentifiersEdit(QLineEdit, ToMetadataMixin):
+class IdentifiersEdit(QLineEdit, ToMetadataMixin, LineEditIndicators):
     LABEL = _('&Ids:')
     BASE_TT = _('Edit the identifiers for this book. '
             'For example: \n\n%s\n\nIf an identifier value contains a comma, you can use the | character to represent it.')%(
@@ -1582,6 +1584,7 @@ class IdentifiersEdit(QLineEdit, ToMetadataMixin):
 
     def __init__(self, parent):
         QLineEdit.__init__(self, parent)
+        self.setup_status_actions()
         self.pat = re.compile(r'[^0-9a-zA-Z]')
         self.textChanged.connect(self.validate)
         self.textChanged.connect(self.data_changed)
@@ -1652,16 +1655,17 @@ class IdentifiersEdit(QLineEdit, ToMetadataMixin):
         isbn = identifiers.get('isbn', '')
         tt = self.BASE_TT
         extra = ''
+        ok = None
         if not isbn:
-            sheet = ''
+            pass
         elif check_isbn(isbn) is not None:
-            sheet = QApplication.instance().stylesheet_for_line_edit()
+            ok = True
             extra = '\n\n'+_('This ISBN is valid')
         else:
-            sheet = QApplication.instance().stylesheet_for_line_edit(True)
+            ok = False
             extra = '\n\n' + _('This ISBN is invalid')
         self.setToolTip(tt+extra)
-        self.setStyleSheet(sheet)
+        self.update_status_actions(ok, self.toolTip())
 
     def paste_identifier(self):
         identifier_found = self.parse_clipboard_for_identifier()
@@ -1751,6 +1755,9 @@ class IdentifiersEdit(QLineEdit, ToMetadataMixin):
         return False
 # }}}
 
+class IndicatorLineEdit(QLineEdit, LineEditIndicators):
+    pass
+
 
 class ISBNDialog(QDialog):  # {{{
 
@@ -1763,7 +1770,8 @@ class ISBNDialog(QDialog):  # {{{
         l.addWidget(w, 0, 0, 1, 2)
         w = QLabel(_('ISBN:'))
         l.addWidget(w, 1, 0, 1, 1)
-        self.line_edit = w = QLineEdit()
+        self.line_edit = w = IndicatorLineEdit()
+        w.setup_status_actions()
         w.setText(txt)
         w.selectAll()
         w.textChanged.connect(self.checkText)
@@ -1787,17 +1795,17 @@ class ISBNDialog(QDialog):  # {{{
 
     def checkText(self, txt):
         isbn = str(txt)
+        ok = None
         if not isbn:
-            sheet = ''
-            extra = ''
+            pass
         elif check_isbn(isbn) is not None:
-            sheet = QApplication.instance().stylesheet_for_line_edit()
             extra = _('This ISBN is valid')
+            ok = True
         else:
-            sheet = QApplication.instance().stylesheet_for_line_edit(True)
             extra = _('This ISBN is invalid')
+            ok = False
         self.line_edit.setToolTip(extra)
-        self.line_edit.setStyleSheet(sheet)
+        self.line_edit.update_status_actions(ok, extra)
 
     def text(self):
         return check_isbn(str(self.line_edit.text()))

src/calibre/gui2/search_box.py

@@ -158,7 +158,6 @@ class SearchBox2(QComboBox):  # {{{
                 items.append(item)
         self.addItems(items)
         self.line_edit.setPlaceholderText(help_text)
-        self.colorize = colorize
         self.clear()
 
     def clear_history(self):
@@ -210,10 +209,6 @@ class SearchBox2(QComboBox):  # {{{
             self.clear(emit_search=False)
             return
         self._in_a_search = ok
-        if self.colorize:
-            self.line_edit.setStyleSheet(QApplication.instance().stylesheet_for_line_edit(not ok))
-        else:
-            self.line_edit.setStyleSheet('')
 
     # Comes from the lineEdit control
     def key_pressed(self, event):
@@ -337,7 +332,7 @@ class SearchBoxMixin:  # {{{
         pass
 
     def init_search_box_mixin(self):
-        self.search.initialize('main_search_history', colorize=True,
+        self.search.initialize('main_search_history',
                 help_text=_('Search (For advanced search click the gear icon to the left)'))
         self.search.cleared.connect(self.search_box_cleared)
         # Queued so that search.current_text will be correct

src/calibre/gui2/widgets.py

@@ -546,6 +546,35 @@ class EnLineEdit(LineEditECM, QLineEdit):  # {{{
 # }}}
 
 
+# LineEditIndicators {{{
+
+def setup_status_actions(self: QLineEdit):
+    self.status_actions = (
+        self.addAction(QIcon.ic('ok.png'), QLineEdit.ActionPosition.TrailingPosition),
+        self.addAction(QIcon.ic('dialog_error.png'), QLineEdit.ActionPosition.TrailingPosition))
+    self.status_actions[0].setVisible(False)
+    self.status_actions[1].setVisible(False)
+
+def update_status_actions(self: QLineEdit, ok, tooltip: str = ''):
+    self.status_actions[0].setVisible(bool(ok))
+    self.status_actions[1].setVisible(not ok)
+    if ok:
+        self.status_actions[0].setToolTip(tooltip)
+    elif ok is None:
+        self.status_actions[1].setVisible(False)
+    else:
+        self.status_actions[1].setToolTip(tooltip)
+
+class LineEditIndicators:
+
+    def setup_status_actions(self):
+        setup_status_actions(self)
+
+    def update_status_actions(self, ok, tooltip=''):
+        update_status_actions(self, ok, tooltip)
+# }}}
+
+
 class ItemsCompleter(QCompleter):  # {{{
 
     '''