from collections.abc import Callable
from AnyQt.QtWidgets import QTextBrowser
from AnyQt.QtGui import QStatusTipEvent, QWhatsThisClickedEvent
from AnyQt.QtCore import QObject, QCoreApplication, QEvent, QTimer, QUrl
from AnyQt.QtCore import pyqtSignal as Signal
[docs]class QuickHelp(QTextBrowser):
#: Emitted when the shown text changes.
textChanged = Signal()
def __init__(self, *args, **kwargs):
super().__init__(*args, **kwargs)
self.setOpenExternalLinks(False)
self.setOpenLinks(False)
self.__text = ""
self.__permanentText = ""
self.__defaultText = ""
self.__timer = QTimer(self, timeout=self.__on_timeout,
singleShot=True)
self.anchorClicked.connect(self.__on_anchorClicked)
[docs] def showHelp(self, text, timeout=0):
"""
Show help for `timeout` milliseconds. if timeout is 0 then
show the text until it is cleared with clearHelp or showHelp is
called with an empty string.
"""
if self.__text != text:
self.__text = text
self.__update()
self.textChanged.emit()
if timeout > 0:
self.__timer.start(timeout)
[docs] def clearHelp(self):
"""
Clear help text previously set with `showHelp`.
"""
self.__timer.stop()
self.showHelp("")
[docs] def showPermanentHelp(self, text):
"""
Set permanent help text. The text may be temporarily overridden
by showHelp but will be shown again when that is cleared.
"""
if self.__permanentText != text:
self.__permanentText = text
self.__update()
self.textChanged.emit()
[docs] def setDefaultText(self, text):
"""
Set default help text. The text is overriden by normal and permanent help messages,
but is show again after such messages are cleared.
"""
if self.__defaultText != text:
self.__defaultText = text
self.__update()
self.textChanged.emit()
[docs] def currentText(self):
"""
Return the current shown text.
"""
return self.__text or self.__permanentText
def __update(self):
if self.__text:
self.setHtml(self.__text)
elif self.__permanentText:
self.setHtml(self.__permanentText)
else:
self.setHtml(self.__defaultText)
def __on_timeout(self):
if self.__text:
self.__text = ""
self.__update()
self.textChanged.emit()
def __on_anchorClicked(self, anchor):
ev = QuickHelpDetailRequestEvent(anchor.toString(), anchor)
QCoreApplication.postEvent(self, ev)
class QuickHelpTipEvent(QStatusTipEvent):
Temporary, Normal, Permanent = range(1, 4)
def __init__(self, tip, html=None, priority=Normal, timeout=None):
super().__init__(tip)
self.__html = html or ""
self.__priority = priority
self.__timeout = timeout
def html(self):
return self.__html
def priority(self):
return self.__priority
def timeout(self):
return self.__timeout
class QuickHelpDetailRequestEvent(QWhatsThisClickedEvent):
def __init__(self, href, url):
super().__init__(href)
self.__url = QUrl(url)
def url(self):
return QUrl(self.__url)
class StatusTipPromoter(QObject):
"""
Promotes `QStatusTipEvent` to `QuickHelpTipEvent` using ``whatsThis``
property of the object.
"""
def eventFilter(self, obj, event):
if event.type() == QEvent.StatusTip and \
not isinstance(event, QuickHelpTipEvent) and \
hasattr(obj, "whatsThis") and \
isinstance(obj.whatsThis, Callable):
tip = event.tip()
try:
text = obj.whatsThis()
except Exception:
text = None
if text:
ev = QuickHelpTipEvent(tip, text if tip else "")
return QCoreApplication.sendEvent(obj, ev)
return super().eventFilter(obj, event)