from ..Qt import QtCore, QtWidgets __all__ = ['TreeWidget', 'TreeWidgetItem'] class TreeWidget(QtWidgets.QTreeWidget): """Extends QTreeWidget to allow internal drag/drop with widgets in the tree. Also maintains the expanded state of subtrees as they are moved. This class demonstrates the absurd lengths one must go to to make drag/drop work.""" sigItemMoved = QtCore.Signal(object, object, object) # (item, parent, index) sigItemCheckStateChanged = QtCore.Signal(object, object) sigItemTextChanged = QtCore.Signal(object, object) sigColumnCountChanged = QtCore.Signal(object, object) # self, count def __init__(self, parent=None): QtWidgets.QTreeWidget.__init__(self, parent) # wrap this item so that we can propagate tree change information # to children. self._invRootItem = InvisibleRootItem(QtWidgets.QTreeWidget.invisibleRootItem(self)) self.setAcceptDrops(True) self.setDragEnabled(True) self.setEditTriggers(QtWidgets.QAbstractItemView.EditTrigger.EditKeyPressed|QtWidgets.QAbstractItemView.EditTrigger.SelectedClicked) self.placeholders = [] self.childNestingLimit = None self.itemClicked.connect(self._itemClicked) def setItemWidget(self, item, col, wid): """ Overrides QTreeWidget.setItemWidget such that widgets are added inside an invisible wrapper widget. This makes it possible to move the item in and out of the tree without its widgets being automatically deleted. """ w = QtWidgets.QWidget() ## foster parent / surrogate child widget l = QtWidgets.QVBoxLayout() l.setContentsMargins(0,0,0,0) w.setLayout(l) w.setSizePolicy(wid.sizePolicy()) w.setMinimumHeight(wid.minimumHeight()) w.setMinimumWidth(wid.minimumWidth()) l.addWidget(wid) w.realChild = wid self.placeholders.append(w) QtWidgets.QTreeWidget.setItemWidget(self, item, col, w) def itemWidget(self, item, col): w = QtWidgets.QTreeWidget.itemWidget(self, item, col) if w is not None and hasattr(w, 'realChild'): w = w.realChild return w def dropMimeData(self, parent, index, data, action): item = self.currentItem() p = parent #print "drop", item, "->", parent, index while True: if p is None: break if p is item: return False #raise Exception("Can not move item into itself.") p = p.parent() if not self.itemMoving(item, parent, index): return False currentParent = item.parent() if currentParent is None: currentParent = self.invisibleRootItem() if parent is None: parent = self.invisibleRootItem() if currentParent is parent and index > parent.indexOfChild(item): index -= 1 self.prepareMove(item) currentParent.removeChild(item) #print " insert child to index", index parent.insertChild(index, item) ## index will not be correct self.setCurrentItem(item) self.recoverMove(item) #self.emit(QtCore.SIGNAL('itemMoved'), item, parent, index) self.sigItemMoved.emit(item, parent, index) return True def itemMoving(self, item, parent, index): """Called when item has been dropped elsewhere in the tree. Return True to accept the move, False to reject.""" return True def prepareMove(self, item): item.__widgets = [] item.__expanded = item.isExpanded() for i in range(self.columnCount()): w = self.itemWidget(item, i) item.__widgets.append(w) if w is None: continue w.setParent(None) for i in range(item.childCount()): self.prepareMove(item.child(i)) def recoverMove(self, item): for i in range(self.columnCount()): w = item.__widgets[i] if w is None: continue self.setItemWidget(item, i, w) for i in range(item.childCount()): self.recoverMove(item.child(i)) item.setExpanded(False) ## Items do not re-expand correctly unless they are collapsed first. QtWidgets.QApplication.instance().processEvents() item.setExpanded(item.__expanded) def collapseTree(self, item): item.setExpanded(False) for i in range(item.childCount()): self.collapseTree(item.child(i)) def removeTopLevelItem(self, item): for i in range(self.topLevelItemCount()): if self.topLevelItem(i) is item: self.takeTopLevelItem(i) return raise Exception("Item '%s' not in top-level items." % str(item)) def listAllItems(self, item=None): items = [] if item is not None: items.append(item) else: item = self.invisibleRootItem() for cindex in range(item.childCount()): foundItems = self.listAllItems(item=item.child(cindex)) for f in foundItems: items.append(f) return items def dropEvent(self, ev): super().dropEvent(ev) self.updateDropFlags() def updateDropFlags(self): ### intended to put a limit on how deep nests of children can go. ### self.childNestingLimit is upheld when moving items without children, but if the item being moved has children/grandchildren, the children/grandchildren ### can end up over the childNestingLimit. if self.childNestingLimit is None: pass # enable drops in all items (but only if there are drops that aren't enabled? for performance...) else: items = self.listAllItems() for item in items: parentCount = 0 p = item.parent() while p is not None: parentCount += 1 p = p.parent() if parentCount >= self.childNestingLimit: item.setFlags(item.flags() & (~QtCore.Qt.ItemFlag.ItemIsDropEnabled)) else: item.setFlags(item.flags() | QtCore.Qt.ItemFlag.ItemIsDropEnabled) @staticmethod def informTreeWidgetChange(item): if hasattr(item, 'treeWidgetChanged'): item.treeWidgetChanged() for i in range(item.childCount()): TreeWidget.informTreeWidgetChange(item.child(i)) def addTopLevelItem(self, item): QtWidgets.QTreeWidget.addTopLevelItem(self, item) self.informTreeWidgetChange(item) def addTopLevelItems(self, items): QtWidgets.QTreeWidget.addTopLevelItems(self, items) for item in items: self.informTreeWidgetChange(item) def insertTopLevelItem(self, index, item): QtWidgets.QTreeWidget.insertTopLevelItem(self, index, item) self.informTreeWidgetChange(item) def insertTopLevelItems(self, index, items): QtWidgets.QTreeWidget.insertTopLevelItems(self, index, items) for item in items: self.informTreeWidgetChange(item) def takeTopLevelItem(self, index): item = self.topLevelItem(index) if item is not None: self.prepareMove(item) item = QtWidgets.QTreeWidget.takeTopLevelItem(self, index) self.prepareMove(item) self.informTreeWidgetChange(item) return item def topLevelItems(self): return [self.topLevelItem(i) for i in range(self.topLevelItemCount())] def clear(self): items = self.topLevelItems() for item in items: self.prepareMove(item) QtWidgets.QTreeWidget.clear(self) ## Why do we want to do this? It causes RuntimeErrors. #for item in items: #self.informTreeWidgetChange(item) def invisibleRootItem(self): return self._invRootItem def itemFromIndex(self, index): """Return the item and column corresponding to a QModelIndex. """ col = index.column() rows = [] while index.row() >= 0: rows.insert(0, index.row()) index = index.parent() item = self.topLevelItem(rows[0]) for row in rows[1:]: item = item.child(row) return item, col def setColumnCount(self, c): QtWidgets.QTreeWidget.setColumnCount(self, c) self.sigColumnCountChanged.emit(self, c) def _itemClicked(self, item, col): if hasattr(item, 'itemClicked'): item.itemClicked(col) class TreeWidgetItem(QtWidgets.QTreeWidgetItem): """ TreeWidgetItem that keeps track of its own widgets and expansion state. * Widgets may be added to columns before the item is added to a tree. * Expanded state may be set before item is added to a tree. * Adds setCheked and isChecked methods. * Adds addChildren, insertChildren, and takeChildren methods. """ def __init__(self, *args): QtWidgets.QTreeWidgetItem.__init__(self, *args) self._widgets = {} # col: widget self._tree = None self._expanded = False def setChecked(self, column, checked): self.setCheckState(column, QtCore.Qt.CheckState.Checked if checked else QtCore.Qt.CheckState.Unchecked) def isChecked(self, col): return self.checkState(col) == QtCore.Qt.CheckState.Checked def setExpanded(self, exp): self._expanded = exp QtWidgets.QTreeWidgetItem.setExpanded(self, exp) def isExpanded(self): return self._expanded def setWidget(self, column, widget): if column in self._widgets: self.removeWidget(column) self._widgets[column] = widget tree = self.treeWidget() if tree is None: return else: tree.setItemWidget(self, column, widget) def removeWidget(self, column): del self._widgets[column] tree = self.treeWidget() if tree is None: return tree.removeItemWidget(self, column) def treeWidgetChanged(self): tree = self.treeWidget() if self._tree is tree: return self._tree = self.treeWidget() if tree is None: return for col, widget in self._widgets.items(): tree.setItemWidget(self, col, widget) QtWidgets.QTreeWidgetItem.setExpanded(self, self._expanded) def childItems(self): return [self.child(i) for i in range(self.childCount())] def addChild(self, child): QtWidgets.QTreeWidgetItem.addChild(self, child) TreeWidget.informTreeWidgetChange(child) def addChildren(self, childs): QtWidgets.QTreeWidgetItem.addChildren(self, childs) for child in childs: TreeWidget.informTreeWidgetChange(child) def insertChild(self, index, child): QtWidgets.QTreeWidgetItem.insertChild(self, index, child) TreeWidget.informTreeWidgetChange(child) def insertChildren(self, index, childs): QtWidgets.QTreeWidgetItem.addChildren(self, index, childs) for child in childs: TreeWidget.informTreeWidgetChange(child) def removeChild(self, child): QtWidgets.QTreeWidgetItem.removeChild(self, child) TreeWidget.informTreeWidgetChange(child) def takeChild(self, index): child = QtWidgets.QTreeWidgetItem.takeChild(self, index) TreeWidget.informTreeWidgetChange(child) return child def takeChildren(self): childs = QtWidgets.QTreeWidgetItem.takeChildren(self) for child in childs: TreeWidget.informTreeWidgetChange(child) return childs def setData(self, column, role, value): # credit: ekhumoro # http://stackoverflow.com/questions/13662020/how-to-implement-itemchecked-and-itemunchecked-signals-for-qtreewidget-in-pyqt4 checkstate = self.checkState(column) text = self.text(column) QtWidgets.QTreeWidgetItem.setData(self, column, role, value) treewidget = self.treeWidget() if treewidget is None: return if (role == QtCore.Qt.ItemDataRole.CheckStateRole and checkstate != self.checkState(column)): treewidget.sigItemCheckStateChanged.emit(self, column) elif (role in (QtCore.Qt.ItemDataRole.DisplayRole, QtCore.Qt.ItemDataRole.EditRole) and text != self.text(column)): treewidget.sigItemTextChanged.emit(self, column) def itemClicked(self, col): """Called when this item is clicked on. Override this method to react to user clicks. """ class InvisibleRootItem(object): """Wrapper around a TreeWidget's invisible root item that calls TreeWidget.informTreeWidgetChange when child items are added/removed. """ def __init__(self, item): self._real_item = item def addChild(self, child): self._real_item.addChild(child) TreeWidget.informTreeWidgetChange(child) def addChildren(self, childs): self._real_item.addChildren(childs) for child in childs: TreeWidget.informTreeWidgetChange(child) def insertChild(self, index, child): self._real_item.insertChild(index, child) TreeWidget.informTreeWidgetChange(child) def insertChildren(self, index, childs): self._real_item.addChildren(index, childs) for child in childs: TreeWidget.informTreeWidgetChange(child) def removeChild(self, child): self._real_item.removeChild(child) TreeWidget.informTreeWidgetChange(child) def takeChild(self, index): child = self._real_item.takeChild(index) TreeWidget.informTreeWidgetChange(child) return child def takeChildren(self): childs = self._real_item.takeChildren() for child in childs: TreeWidget.informTreeWidgetChange(child) return childs def __getattr__(self, attr): return getattr(self._real_item, attr)