许多专业应用程序(例如Web浏览器)使用户能够从选项卡栏中分离选项卡.令人惊讶的是,Qt4不提供此功能.有些人可能会说使用表格化的QDockWidgets提供此功能.但是,也可以认为QDockWidgets实现使用户看起来不专业且不直观.
解决方法:
我在Qt中心论坛上找到了this post中部分工作的C示例.这是不完整和错误的.但是,我能够使用它作为参考和起点,使用PyQt创建我自己的DetachableTabWidget.由于我无法在PyQt中找到任何其他功能完备的例子,我想在此发布.也许对某人有用.
我不会称之为完美,所以我绝对愿意接受任何改进建议.
EDIT1
上一次迭代有一些严重的缺陷,直到我尝试在实际应用程序中使用它时才发现.我使用QDialog作为分离的选项卡,这意味着它们无法像典型的窗口那样被最小化或最大化.我也让它们成为选项卡主机的父级,这意味着分离的选项卡始终位于选项卡主机的顶部.以下是我的新版本,它使用QMainWindow作为分离的选项卡.
EDIT2
如Qt的文档中所述,QDrag.exec_()在Windows和Linux之间的行为有所不同.这导致我为EDIT1发布的迭代失去了在Linux中移动(重新排序)选项卡的能力.我对这个迭代做了一个小修复,现在它可以在Windows和Linux上运行.我还更新了评论,以反映从QDialog到QMainWindow的交换.
EDIT3
我添加了一个removeTabByName(name)函数,该函数将按名称删除选项卡,即使它已分离.
我添加了通过将标签拖回标签栏区域来重新附加标签的功能.如果它被放在另一个标签上,它将被插入该位置.如果它被拖放到选项卡栏旁边,它将作为最后一个选项卡附加.如果所有选项卡都已分离,则将DetachedTabWidget中的分离选项卡放在任何位置将重新附加选项卡.
from PyQt4 import QtGui, QtCore
from PyQt4.QtCore import pyqtSignal, pyqtSlot
##
# The DetachableTabWidget adds additional functionality to Qt's QTabWidget that allows it
# to detach and re-attach tabs.
#
# Additional Features:
# Detach tabs by
# dragging the tabs away from the tab bar
# double clicking the tab
# Re-attach tabs by
# dragging the detached tab's window into the tab bar
# closing the detached tab's window
# Remove tab (attached or detached) by name
#
# Modified Features:
# Re-ordering (moving) tabs by dragging was re-implemented
#
class DetachableTabWidget(QtGui.QTabWidget):
def __init__(self, parent=None):
QtGui.QTabWidget.__init__(self, parent)
self.tabBar = self.TabBar(self)
self.tabBar.onDetachTabSignal.connect(self.detachTab)
self.tabBar.onMoveTabSignal.connect(self.moveTab)
self.tabBar.detachedTabDropSignal.connect(self.detachedTabDrop)
self.setTabBar(self.tabBar)
# Used to keep a reference to detached tabs since their QMainWindow
# does not have a parent
self.detachedTabs = {}
# Close all detached tabs if the application is closed explicitly
QtGui.qApp.aboutToQuit.connect(self.closeDetachedTabs) # @UndefinedVariable
##
# The default movable functionality of QTabWidget must remain disabled
# so as not to conflict with the added features
def setMovable(self, movable):
pass
##
# Move a tab from one position (index) to another
#
# @param fromIndex the original index location of the tab
# @param toIndex the new index location of the tab
@pyqtSlot(int, int)
def moveTab(self, fromIndex, toIndex):
widget = self.widget(fromIndex)
icon = self.tabIcon(fromIndex)
text = self.tabText(fromIndex)
self.removeTab(fromIndex)
self.insertTab(toIndex, widget, icon, text)
self.setCurrentIndex(toIndex)
##
# Detach the tab by removing it's contents and placing them in
# a DetachedTab window
#
# @param index the index location of the tab to be detached
# @param point the screen position for creating the new DetachedTab window
@pyqtSlot(int, QtCore.QPoint)
def detachTab(self, index, point):
# Get the tab content
name = self.tabText(index)
icon = self.tabIcon(index)
if icon.isNull():
icon = self.window().windowIcon()
contentWidget = self.widget(index)
try:
contentWidgetRect = contentWidget.frameGeometry()
except AttributeError:
return
# Create a new detached tab window
detachedTab = self.DetachedTab(name, contentWidget)
detachedTab.setWindowModality(QtCore.Qt.NonModal)
detachedTab.setWindowIcon(icon)
detachedTab.setGeometry(contentWidgetRect)
detachedTab.onCloseSignal.connect(self.attachTab)
detachedTab.onDropSignal.connect(self.tabBar.detachedTabDrop)
detachedTab.move(point)
detachedTab.show()
# Create a reference to maintain access to the detached tab
self.detachedTabs[name] = detachedTab
##
# Re-attach the tab by removing the content from the DetachedTab window,
# closing it, and placing the content back into the DetachableTabWidget
#
# @param contentWidget the content widget from the DetachedTab window
# @param name the name of the detached tab
# @param icon the window icon for the detached tab
# @param insertAt insert the re-attached tab at the given index
def attachTab(self, contentWidget, name, icon, insertAt=None):
# Make the content widget a child of this widget
contentWidget.setParent(self)
# Remove the reference
del self.detachedTabs[name]
# Create an image from the given icon (for comparison)
if not icon.isNull():
try:
tabIconPixmap = icon.pixmap(icon.availableSizes()[0])
tabIconImage = tabIconPixmap.toImage()
except IndexError:
tabIconImage = None
else:
tabIconImage = None
# Create an image of the main window icon (for comparison)
if not icon.isNull():
try:
windowIconPixmap = self.window().windowIcon().pixmap(icon.availableSizes()[0])
windowIconImage = windowIconPixmap.toImage()
except IndexError:
windowIconImage = None
else:
windowIconImage = None
# Determine if the given image and the main window icon are the same.
# If they are, then do not add the icon to the tab
if tabIconImage == windowIconImage:
if insertAt == None:
index = self.addTab(contentWidget, name)
else:
index = self.insertTab(insertAt, contentWidget, name)
else:
if insertAt == None:
index = self.addTab(contentWidget, icon, name)
else:
index = self.insertTab(insertAt, contentWidget, icon, name)
# Make this tab the current tab
if index > -1:
self.setCurrentIndex(index)
##
# Remove the tab with the given name, even if it is detached
#
# @param name the name of the tab to be removed
def removeTabByName(self, name):
# Remove the tab if it is attached
attached = False
for index in xrange(self.count()):
if str(name) == str(self.tabText(index)):
self.removeTab(index)
attached = True
break
# If the tab is not attached, close it's window and
# remove the reference to it
if not attached:
for key in self.detachedTabs:
if str(name) == str(key):
self.detachedTabs[key].onCloseSignal.disconnect()
self.detachedTabs[key].close()
del self.detachedTabs[key]
break
##
# Handle dropping of a detached tab inside the DetachableTabWidget
#
# @param name the name of the detached tab
# @param index the index of an existing tab (if the tab bar
# determined that the drop occurred on an
# existing tab)
# @param dropPos the mouse cursor position when the drop occurred
@QtCore.pyqtSlot(QtCore.QString, int, QtCore.QPoint)
def detachedTabDrop(self, name, index, dropPos):
# If the drop occurred on an existing tab, insert the detached
# tab at the existing tab's location
if index > -1:
# Create references to the detached tab's content and icon
contentWidget = self.detachedTabs[name].contentWidget
icon = self.detachedTabs[name].windowIcon()
# Disconnect the detached tab's onCloseSignal so that it
# does not try to re-attach automatically
self.detachedTabs[name].onCloseSignal.disconnect()
# Close the detached
self.detachedTabs[name].close()
# Re-attach the tab at the given index
self.attachTab(contentWidget, name, icon, index)
# If the drop did not occur on an existing tab, determine if the drop
# occurred in the tab bar area (the area to the side of the QTabBar)
else:
# Find the drop position relative to the DetachableTabWidget
tabDropPos = self.mapFromGlobal(dropPos)
# If the drop position is inside the DetachableTabWidget...
if self.rect().contains(tabDropPos):
# If the drop position is inside the tab bar area (the
# area to the side of the QTabBar) or there are not tabs
# currently attached...
if tabDropPos.y() < self.tabBar.height() or self.count() == 0:
# Close the detached tab and allow it to re-attach
# automatically
self.detachedTabs[name].close()
##
# Close all tabs that are currently detached.
def closeDetachedTabs(self):
listOfDetachedTabs = []
for key in self.detachedTabs:
listOfDetachedTabs.append(self.detachedTabs[key])
for detachedTab in listOfDetachedTabs:
detachedTab.close()
##
# When a tab is detached, the contents are placed into this QMainWindow. The tab
# can be re-attached by closing the dialog or by dragging the window into the tab bar
class DetachedTab(QtGui.QMainWindow):
onCloseSignal = pyqtSignal(QtGui.QWidget, QtCore.QString, QtGui.QIcon)
onDropSignal = pyqtSignal(QtCore.QString, QtCore.QPoint)
def __init__(self, name, contentWidget):
QtGui.QMainWindow.__init__(self, None)
self.setObjectName(name)
self.setWindowTitle(name)
self.contentWidget = contentWidget
self.setCentralWidget(self.contentWidget)
self.contentWidget.show()
self.windowDropFilter = self.WindowDropFilter()
self.installEventFilter(self.windowDropFilter)
self.windowDropFilter.onDropSignal.connect(self.windowDropSlot)
##
# Handle a window drop event
#
# @param dropPos the mouse cursor position of the drop
@QtCore.pyqtSlot(QtCore.QPoint)
def windowDropSlot(self, dropPos):
self.onDropSignal.emit(self.objectName(), dropPos)
##
# If the window is closed, emit the onCloseSignal and give the
# content widget back to the DetachableTabWidget
#
# @param event a close event
def closeEvent(self, event):
self.onCloseSignal.emit(self.contentWidget, self.objectName(), self.windowIcon())
##
# An event filter class to detect a QMainWindow drop event
class WindowDropFilter(QtCore.QObject):
onDropSignal = pyqtSignal(QtCore.QPoint)
def __init__(self):
QtCore.QObject.__init__(self)
self.lastEvent = None
##
# Detect a QMainWindow drop event by looking for a NonClientAreaMouseMove (173)
# event that immediately follows a Move event
#
# @param obj the object that generated the event
# @param event the current event
def eventFilter(self, obj, event):
# If a NonClientAreaMouseMove (173) event immediately follows a Move event...
if self.lastEvent == QtCore.QEvent.Move and event.type() == 173:
# Determine the position of the mouse cursor and emit it with the
# onDropSignal
mouseCursor = QtGui.QCursor()
dropPos = mouseCursor.pos()
self.onDropSignal.emit(dropPos)
self.lastEvent = event.type()
return True
else:
self.lastEvent = event.type()
return False
##
# The TabBar class re-implements some of the functionality of the QTabBar widget
class TabBar(QtGui.QTabBar):
onDetachTabSignal = pyqtSignal(int, QtCore.QPoint)
onMoveTabSignal = pyqtSignal(int, int)
detachedTabDropSignal = pyqtSignal(QtCore.QString, int, QtCore.QPoint)
def __init__(self, parent=None):
QtGui.QTabBar.__init__(self, parent)
self.setAcceptDrops(True)
self.setElideMode(QtCore.Qt.ElideRight)
self.setSelectionBehaviorOnRemove(QtGui.QTabBar.SelectLeftTab)
self.dragStartPos = QtCore.QPoint()
self.dragDropedPos = QtCore.QPoint()
self.mouseCursor = QtGui.QCursor()
self.dragInitiated = False
##
# Send the onDetachTabSignal when a tab is double clicked
#
# @param event a mouse double click event
def mouseDoubleClickEvent(self, event):
event.accept()
self.onDetachTabSignal.emit(self.tabAt(event.pos()), self.mouseCursor.pos())
##
# Set the starting position for a drag event when the mouse button is pressed
#
# @param event a mouse press event
def mousePressEvent(self, event):
if event.button() == QtCore.Qt.LeftButton:
self.dragStartPos = event.pos()
self.dragDropedPos.setX(0)
self.dragDropedPos.setY(0)
self.dragInitiated = False
QtGui.QTabBar.mousePressEvent(self, event)
##
# Determine if the current movement is a drag. If it is, convert it into a QDrag. If the
# drag ends inside the tab bar, emit an onMoveTabSignal. If the drag ends outside the tab
# bar, emit an onDetachTabSignal.
#
# @param event a mouse move event
def mouseMoveEvent(self, event):
# Determine if the current movement is detected as a drag
if not self.dragStartPos.isNull() and ((event.pos() - self.dragStartPos).manhattanLength() < QtGui.QApplication.startDragDistance()):
self.dragInitiated = True
# If the current movement is a drag initiated by the left button
if (((event.buttons() & QtCore.Qt.LeftButton)) and self.dragInitiated):
# Stop the move event
finishMoveEvent = QtGui.QMouseEvent(QtCore.QEvent.MouseMove, event.pos(), QtCore.Qt.NoButton, QtCore.Qt.NoButton, QtCore.Qt.NoModifier)
QtGui.QTabBar.mouseMoveEvent(self, finishMoveEvent)
# Convert the move event into a drag
drag = QtGui.QDrag(self)
mimeData = QtCore.QMimeData()
mimeData.setData('action', 'application/tab-detach')
drag.setMimeData(mimeData)
# Create the appearance of dragging the tab content
pixmap = QtGui.QPixmap.grabWindow(self.parentWidget().currentWidget().winId())
targetPixmap = QtGui.QPixmap(pixmap.size())
targetPixmap.fill(QtCore.Qt.transparent)
painter = QtGui.QPainter(targetPixmap)
painter.setOpacity(0.85)
painter.drawPixmap(0, 0, pixmap)
painter.end()
drag.setPixmap(targetPixmap)
# Initiate the drag
dropAction = drag.exec_(QtCore.Qt.MoveAction | QtCore.Qt.CopyAction)
# For Linux: Here, drag.exec_() will not return MoveAction on Linux. So it
# must be set manually
if self.dragDropedPos.x() != 0 and self.dragDropedPos.y() != 0:
dropAction = QtCore.Qt.MoveAction
# If the drag completed outside of the tab bar, detach the tab and move
# the content to the current cursor position
if dropAction == QtCore.Qt.IgnoreAction:
event.accept()
self.onDetachTabSignal.emit(self.tabAt(self.dragStartPos), self.mouseCursor.pos())
# Else if the drag completed inside the tab bar, move the selected tab to the new position
elif dropAction == QtCore.Qt.MoveAction:
if not self.dragDropedPos.isNull():
event.accept()
self.onMoveTabSignal.emit(self.tabAt(self.dragStartPos), self.tabAt(self.dragDropedPos))
else:
QtGui.QTabBar.mouseMoveEvent(self, event)
##
# Determine if the drag has entered a tab position from another tab position
#
# @param event a drag enter event
def dragEnterEvent(self, event):
mimeData = event.mimeData()
formats = mimeData.formats()
if formats.contains('action') and mimeData.data('action') == 'application/tab-detach':
event.acceptProposedAction()
QtGui.QTabBar.dragMoveEvent(self, event)
##
# Get the position of the end of the drag
#
# @param event a drop event
def dropEvent(self, event):
self.dragDropedPos = event.pos()
QtGui.QTabBar.dropEvent(self, event)
##
# Determine if the detached tab drop event occurred on an existing tab,
# then send the event to the DetachableTabWidget
def detachedTabDrop(self, name, dropPos):
tabDropPos = self.mapFromGlobal(dropPos)
index = self.tabAt(tabDropPos)
self.detachedTabDropSignal.emit(name, index, dropPos)
if __name__ == '__main__':
import sys
app = QtGui.QApplication(sys.argv)
mainWindow = QtGui.QMainWindow()
tabWidget = DetachableTabWidget()
tab1 = QtGui.QLabel('Test Widget 1')
tabWidget.addTab(tab1, 'Tab1')
tab2 = QtGui.QLabel('Test Widget 2')
tabWidget.addTab(tab2, 'Tab2')
tab3 = QtGui.QLabel('Test Widget 3')
tabWidget.addTab(tab3, 'Tab3')
tabWidget.show()
mainWindow.setCentralWidget(tabWidget)
mainWindow.show()
try:
exitStatus = app.exec_()
print 'Done...'
sys.exit(exitStatus)
except:
pass
缺点
与Web浏览器不同,关闭窗口(分离选项卡)将始终将其重新附加到选项卡栏.在将来我想添加一个选项,以便能够关闭窗口而不是重新连接.
我仍然需要添加一个方法来从窗口小部件外部获取对分离选项卡的引用.
错误
任何有关这些的帮助将不胜感激.
>在极少数情况下,通过拖动删除选项卡时,拖动事件不会被检测为拖动.这是非常罕见的,我没有花太多时间在它上面.
>有时当分离选项卡时,保存分离选项卡的QMainWindow不会生成NonClientAreaMouseMove事件.让它再次开始生成此事件的唯一方法是让QMainWindow松散并重新获得焦点.我不确定这是不是我的错误.