pyqtgraph/widgets/TreeWidget.py
2013-12-23 11:16:39 -05:00

285 lines
10 KiB
Python

# -*- coding: utf-8 -*-
from ..Qt import QtGui, QtCore
from weakref import *
__all__ = ['TreeWidget', 'TreeWidgetItem']
class TreeWidget(QtGui.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)
def __init__(self, parent=None):
QtGui.QTreeWidget.__init__(self, parent)
#self.itemWidgets = WeakKeyDictionary()
self.setAcceptDrops(True)
self.setDragEnabled(True)
self.setEditTriggers(QtGui.QAbstractItemView.EditKeyPressed|QtGui.QAbstractItemView.SelectedClicked)
self.placeholders = []
self.childNestingLimit = None
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 = QtGui.QWidget() ## foster parent / surrogate child widget
l = QtGui.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)
QtGui.QTreeWidget.setItemWidget(self, item, col, w)
def itemWidget(self, item, col):
w = QtGui.QTreeWidget.itemWidget(self, item, col)
if w is not None:
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.
QtGui.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 != 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):
QtGui.QTreeWidget.dropEvent(self, 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 == 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.ItemIsDropEnabled))
else:
item.setFlags(item.flags() | QtCore.Qt.ItemIsDropEnabled)
@staticmethod
def informTreeWidgetChange(item):
if hasattr(item, 'treeWidgetChanged'):
item.treeWidgetChanged()
else:
for i in xrange(item.childCount()):
TreeWidget.informTreeWidgetChange(item.child(i))
def addTopLevelItem(self, item):
QtGui.QTreeWidget.addTopLevelItem(self, item)
self.informTreeWidgetChange(item)
def addTopLevelItems(self, items):
QtGui.QTreeWidget.addTopLevelItems(self, items)
for item in items:
self.informTreeWidgetChange(item)
def insertTopLevelItem(self, index, item):
QtGui.QTreeWidget.insertTopLevelItem(self, index, item)
self.informTreeWidgetChange(item)
def insertTopLevelItems(self, index, items):
QtGui.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 = QtGui.QTreeWidget.takeTopLevelItem(self, index)
self.prepareMove(item)
self.informTreeWidgetChange(item)
return item
def topLevelItems(self):
return map(self.topLevelItem, xrange(self.topLevelItemCount()))
def clear(self):
items = self.topLevelItems()
for item in items:
self.prepareMove(item)
QtGui.QTreeWidget.clear(self)
## Why do we want to do this? It causes RuntimeErrors.
#for item in items:
#self.informTreeWidgetChange(item)
class TreeWidgetItem(QtGui.QTreeWidgetItem):
"""
TreeWidgetItem that keeps track of its own widgets.
Widgets may be added to columns before the item is added to a tree.
"""
def __init__(self, *args):
QtGui.QTreeWidgetItem.__init__(self, *args)
self._widgets = {} # col: widget
self._tree = None
def setChecked(self, column, checked):
self.setCheckState(column, QtCore.Qt.Checked if checked else QtCore.Qt.Unchecked)
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)
def addChild(self, child):
QtGui.QTreeWidgetItem.addChild(self, child)
TreeWidget.informTreeWidgetChange(child)
def addChildren(self, childs):
QtGui.QTreeWidgetItem.addChildren(self, childs)
for child in childs:
TreeWidget.informTreeWidgetChange(child)
def insertChild(self, index, child):
QtGui.QTreeWidgetItem.insertChild(self, index, child)
TreeWidget.informTreeWidgetChange(child)
def insertChildren(self, index, childs):
QtGui.QTreeWidgetItem.addChildren(self, index, childs)
for child in childs:
TreeWidget.informTreeWidgetChange(child)
def removeChild(self, child):
QtGui.QTreeWidgetItem.removeChild(self, child)
TreeWidget.informTreeWidgetChange(child)
def takeChild(self, index):
child = QtGui.QTreeWidgetItem.takeChild(self, index)
TreeWidget.informTreeWidgetChange(child)
return child
def takeChildren(self):
childs = QtGui.QTreeWidgetItem.takeChildren(self)
for child in childs:
TreeWidget.informTreeWidgetChange(child)
return childs