计算QTextEdit的高度

Question

我在QListWidget中有一个QTextEdit，我需要能够计算QTextEdit的高度，以便可以在列表中设置QListWidgetItem的大小提示。我想出了如何获得一条线的高度并将其乘以行数，但是QTextEdit.document().lineCount()每次都会返回1。我认为这是因为尚未设置文档的宽度，因此它还没有弄清楚如何拆分行。如果正确，那么在查询行数之前，我将如何强制它“布置”文本？所有这些都需要在绘画事件之前发生。

list = QtGui.QListWidget()

text = QtGui.QTextEdit()
text.setHtml("Some html stuff in here that spans multiple lines")

fm = QtGui.QFontMetricsF(text.font())
height = text.document().lineCount() * fm.lineSpacing()
text.setFixedHeight(height + 10)

item = QtGui.QListWidgetItem()
item.setSizeHint(text.size())
list.addItem(item)

Answer 1

我不知道您到底想要什么，但是我想尝试一下。临近您想要的内容吗？

from PyQt4 import QtGui, QtCore
import sys
class CustomListView(QtGui.QListView):
    def __init__(self, parent=None):
        super(CustomListView, self).__init__(parent=None)
        pass
class ListItem(object):
    def __init__(self, html = "Some html stuff in here that spans multiple lines"*100):
        self.html = html

class CustomListModel(QtCore.QAbstractListModel):
    def __init__(self, parent=None):
        super(CustomListModel, self).__init__(parent=None)
        self.items = [ListItem()]
    def rowCount(self, index=QtCore.QModelIndex()):
        return len(self.items)
    def columnCount(self, index= QtCore.QModelIndex()):
        return 1
    def data(self, index = QtCore.QModelIndex(), role=QtCore.Qt.ItemDataRole.DisplayRole):
        row = index.row()
        if role == QtCore.Qt.ItemDataRole.DisplayRole:
            return self.items[row]
    def setData(self, index, value, role=QtCore.Qt.EditRole):
        if role == QtCore.Qt.EditRole:
            row = index.row()
            item = self.items[row]
            item.html = value
            return True
    def flags(self, index):
        return QtCore.Qt.ItemFlag.ItemIsEditable|QtCore.Qt.ItemFlag.ItemIsEnabled|QtCore.Qt.ItemFlag.ItemIsSelectable
class StyledItemDelegate(QtGui.QStyledItemDelegate):
    def __init__(self, parent=None):
        super(StyledItemDelegate, self).__init__(parent=None)
        self.doc = QtGui.QTextDocument(self)
        limitSize = QtCore.QSizeF(797, 1123)
        self.doc.setPageSize(limitSize)
    def paint(self, painter, option, index):        
        painter.save()
        pen = painter.pen()
        pen.setWidth(5)
        pen.setStyle(QtCore.Qt.PenStyle.SolidLine)
        painter.setPen(pen)
        brush = painter.brush()
        brush.setStyle(QtCore.Qt.BrushStyle.SolidPattern)
        brush.setColor(QtCore.Qt.blue)
        painter.setBrush(brush)
        data = index.data(QtCore.Qt.ItemDataRole.DisplayRole)
        self.doc.setHtml(data.html)
        option = QtGui.QStyleOptionViewItemV4(option)
        style = QtGui.QApplication.style() if option.widget is None \
            else option.widget.style()
        textRect = style.subElementRect(QtGui.QStyle.SE_ItemViewItemText, option, None)
        ctx = QtGui.QAbstractTextDocumentLayout.PaintContext()
        ctx.clip = textRect
        self.doc.drawContents(painter, ctx.clip)
        painter.restore()
    def sizeHint(self, option, index):        
        data = index.data(QtCore.Qt.ItemDataRole.DisplayRole)       
        self.doc.setHtml(data.html)          
        size = self.doc.size().toSize()
        return size
    def createEditor(self, parent, option, index):     
        data = index.data(QtCore.Qt.DisplayRole)
        parent = QtGui.QTextEdit(parent)
        parent.setFixedSize(self.sizeHint(option, index))
        parent.setHtml(data.html)        
        return parent
    def setEditorData(self, editor, index):
        data = index.data(QtCore.Qt.DisplayRole)
        editor.setHtml(data.html)
    def setModelData(self, editor, model, index):
        html = editor.toHtml()
        model.setData(index, html)

def main():
    if QtGui.QApplication.instance() is None:
        app = QtGui.QApplication([])
    else:
        app = QtGui.QApplication.instance()        
    list = CustomListView()
    model = CustomListModel()
    list.setModel(model)
    delegate = StyledItemDelegate()
    list.setItemDelegate(delegate) 
    list.show()
    sys.exit(app.exec_())
if __name__ == "__main__":
    main()