递归很好,应该保持不变。针对你主要的问题,只需要这样做:
# after all your code
add_items(self.tree_widget, self.xml)
# select the root item
self.tree_widget.setCurrentItem(self.tree_widget.topLevelItem(0))
当你调用setCurrentItem时,确保该项已经被添加到树中,否则它不会真正起作用。有些方法要求该项已经与树相关联(例如setExpanded和setSelected)。
编辑
要递归地建立树结构而不影响树,请执行以下操作:
import lxml.etree as et
self.xml = et.XML(filters.filtersxml)
self.tree_widget = QTreeWidget(parent)
def add_items(parent, xmlroot):
output = []
for i in xmlroot.getchildren():
item = QTreeWidgetItem(parent, [i.get('name')])
output.append(item)
if len(i.getchildren()) != 0:
add_items(item, i)
return output
items = add_items(None, self.xml)
self.tree_widget.addTopLevelItems(items)
self.tree_widget.setCurrentItem(items[0])
编辑2:一次性全部加载
为了更进一步地进行优化,我个人会这样做来尽可能减少不必要的调用和列表:只构建一次子级循环:
import lxml.etree as et
self.xml = et.XML(filters.filtersxml)
self.tree_widget = QTreeWidget(parent)
def create_item(parent, xmlroot):
item = QTreeWidgetItem(parent, [xmlroot.get('name')])
for xmlchild in xmlroot.getchildren():
create_item(item, xmlchild)
return item
items = [create_item(None, xmlchild) for xmlchild in self.xml.getchildren()]
self.tree_widget.addTopLevelItems(items)
if ( items ):
self.tree_widget.setCurrentItem(items[0])
编辑 3:动态加载
既然提到了…一种动态加载子级的方法是存储每个层级,然后在展开后加载它们:
import lxml.etree as et
from PyQt4.QtGui import QTreeWidgetItem
class XmlTreeWidgetItem(QTreeWidgetItem):
def __init__( self, parent, xmlitem ):
super(MyTreeWidgetItem, self).__init__(parent)
self.setText(0, xmlitem.get('name'))
self.setChildIndicatorPolicy(self.ShowIndicator)
self._xmlitem = xmlitem
self._loaded = False
def loadChildren( self ):
if ( self._loaded ):
return
self._loaded = True
self.setChildIndicatorPolicy(self.DontShowIndicatorWhenChildless)
for xmlchild in self._xmlitem.getchildren():
XmlTreeWidgetItem(self, xmlchild)
class SomeClass(QWidget):
def __init__( self, parent = None ):
super(SomeClass, self).__init__(parent)
self.tree_widget = QTreeWidget(parent)
xml = et.XML(filters.filtersxml)
items = [XmlTreeWidgetItem(None, xchild) for xchild in xml.getchildren()]
self.tree_widget.addTopLevelItems(items)
if ( items ):
self.tree_widget.setCurrentItem(items[0])
self.tree_widget.itemExpanded.connect(self.loadItem)
def loadItem( self, item ):
item.loadChildren()
if parent is None
? - jdi