<p>最简单的方法似乎是通过子类化<code>QItemDelegate</code>,因为文本是由一个单独的虚函数<code>drawDisplay</code>(使用<code>QStyledItemDelegate</code>你几乎必须从头开始重新绘制项目,并且需要从<code>QProxyStyle</code>派生的附加类):</p>
<ul>
<li>HTML文本用<code>QTextDocument</code>和<code>QTextDocument.documentLayout().draw()</code>绘制</li>
<li>当鼠标进入一个项目时,该项目被重新绘制并调用<code>drawDisplay</code>,我们保存了绘制文本时的位置(因此保存的位置始终是鼠标所在项目的文本位置)</li>
<li>该位置用于<code>editorEvent</code>中,以获取文档中鼠标的相对位置,并使用<code>QAbstractTextDocumentLayout.anchorAt</code>获取文档中该位置的链接。在</li>
</ul>
<pre class="lang-py prettyprint-override"><code>import sys
from PySide.QtCore import *
from PySide.QtGui import *
class LinkItemDelegate(QItemDelegate):
linkActivated = Signal(str)
linkHovered = Signal(str) # to connect to a QStatusBar.showMessage slot
def __init__(self, parentView):
QItemDelegate.__init__(self, parentView)
assert isinstance(parentView, QAbstractItemView), \
"The first argument must be the view"
# We need that to receive mouse move events in editorEvent
parentView.setMouseTracking(True)
# Revert the mouse cursor when the mouse isn't over
# an item but still on the view widget
parentView.viewportEntered.connect(parentView.unsetCursor)
# documents[0] will contain the document for the last hovered item
# documents[1] will be used to draw ordinary (not hovered) items
self.documents = []
for i in range(2):
self.documents.append(QTextDocument(self))
self.documents[i].setDocumentMargin(0)
self.lastTextPos = QPoint(0,0)
def drawDisplay(self, painter, option, rect, text):
# Because the state tells only if the mouse is over the row
# we have to check if it is over the item too
mouseOver = option.state & QStyle.State_MouseOver \
and rect.contains(self.parent().viewport() \
.mapFromGlobal(QCursor.pos())) \
and option.state & QStyle.State_Enabled
if mouseOver:
# Use documents[0] and save the text position for editorEvent
doc = self.documents[0]
self.lastTextPos = rect.topLeft()
doc.setDefaultStyleSheet("")
else:
doc = self.documents[1]
# Links are decorated by default, so disable it
# when the mouse is not over the item
doc.setDefaultStyleSheet("a {text-decoration: none}")
doc.setDefaultFont(option.font)
doc.setHtml(text)
painter.save()
painter.translate(rect.topLeft())
ctx = QAbstractTextDocumentLayout.PaintContext()
ctx.palette = option.palette
doc.documentLayout().draw(painter, ctx)
painter.restore()
def editorEvent(self, event, model, option, index):
if event.type() not in [QEvent.MouseMove, QEvent.MouseButtonRelease] \
or not (option.state & QStyle.State_Enabled):
return False
# Get the link at the mouse position
# (the explicit QPointF conversion is only needed for PyQt)
pos = QPointF(event.pos() - self.lastTextPos)
anchor = self.documents[0].documentLayout().anchorAt(pos)
if anchor == "":
self.parent().unsetCursor()
else:
self.parent().setCursor(Qt.PointingHandCursor)
if event.type() == QEvent.MouseButtonRelease:
self.linkActivated.emit(anchor)
return True
else:
self.linkHovered.emit(anchor)
return False
def sizeHint(self, option, index):
# The original size is calculated from the string with the html tags
# so we need to subtract from it the difference between the width
# of the text with and without the html tags
size = QItemDelegate.sizeHint(self, option, index)
# Use a QTextDocument to strip the tags
doc = self.documents[1]
html = index.data() # must add .toString() for PyQt "API 1"
doc.setHtml(html)
plainText = doc.toPlainText()
fontMetrics = QFontMetrics(option.font)
diff = fontMetrics.width(html) - fontMetrics.width(plainText)
return size - QSize(diff, 0)
</code></pre>
<p>只要不启用按内容自动调整列大小(这将为每个项调用sizeHint),它似乎不会比没有委托慢。<br/>对于自定义模型,可以通过在模型内直接缓存一些数据(例如,使用和存储QStaticText来代替QTextDocument)来加快速度。在</p>