QListWiget - Flow "BottomToTop"？

Question

我想知道缺失的flow()属性"BottomToTop“是否有解决方法？

我目前正在做一个小小的宠物项目。一个简单的QListWidget，包含一个由用户添加的定制QWidget项。这部分没问题。我只想要列出的项目是"BottomToTop“。有什么建议吗？

Answer 1

是否只需要在列表的底部而不是顶部插入新元素？

我假设你的列表的开头是你所谓的底部？

如果是这样，您可以使用QListWidget::insertItem

yourListWidget->(0, yourNewWidgetItem);

Answer 2

这是我一直在问的问题的最接近的解决方案(归功于-ymoreau的Spacer想法)。但我对此并不完全满意。当添加了足够多的项目并且滚动条出现时，底部会出现一个令人讨厌的(在我看来)空白区域。有什么解决方案吗？和ofc。有没有更优雅的解决方案呢？在我看来有点过分了..。

from PyQt5.QtWidgets import (QApplication, QWidget, QListWidget,
                             QListWidgetItem, QVBoxLayout, QHBoxLayout,
                             QPushButton, QSpacerItem, QLabel, QSizePolicy)
from PyQt5.QtCore import QSize
from PyQt5 import QtCore

import sys


class SpacerWidget(QWidget):
    def __init__(self, parent=None):
        super(SpacerWidget, self).__init__(parent)

        self.spacer = QSpacerItem(self.width(), self.height(),
                                  QSizePolicy.Expanding,
                                  QSizePolicy.Expanding)

        self.setStyleSheet("border: none;")
        
        self.layout = QHBoxLayout()
        self.layout.setSpacing(0)
        self.layout.setContentsMargins(0, 0, 0, 0)

        self.layout.addItem(self.spacer)
        self.setLayout(self.layout)


class SpacerWidgetItem(QListWidgetItem):
    def __init__(self, parent=None):
        super(SpacerWidgetItem, self).__init__(parent)

    def setSize(self, width, new_height):

        if new_height < 10:
            self.setSizeHint(QSize(0, 0))
        else:
            self.setSizeHint(QSize(width, new_height))
        

class ItemWidget(QWidget):
    def __init__(self, parent=None):
        super(ItemWidget, self).__init__(parent)

        self.left_label = QLabel("Some info!")
        self.left_label.setMaximumHeight(35)
        self.left_label.setAlignment(QtCore.Qt.AlignLeft)

        self.right_label = QLabel("Some other info!")
        self.right_label.setMaximumHeight(35)
        self.right_label.setAlignment(QtCore.Qt.AlignRight)
        
        self.layout = QHBoxLayout()
        self.layout.setSpacing(0)
        self.layout.addWidget(self.left_label)
        self.layout.addWidget(self.right_label)
        self.setLayout(self.layout)
        

class Widget(QWidget):
    def __init__(self):
        super().__init__()
        self.initUI()

    def initUI(self):
        
        self.resize(300, 320)

        self.itemsinlist = 0

        self.layout = QVBoxLayout()

        self.add_btn = QPushButton("Add Item")
        self.add_btn.setMinimumSize(QSize(300, 50))
        self.add_btn.clicked.connect(self.addListItem)
        
        self.list_w = QListWidget()
        self.list_w.setMinimumSize(300, 270)
        self.list_w.resize(300, 270)
        self.list_w.setHorizontalScrollBarPolicy(QtCore.Qt.ScrollBarAlwaysOff)
        self.list_w.setResizeMode(1)

        self.spacer = SpacerWidgetItem(self.list_w)
        self.spacer.setSizeHint(QSize(self.list_w.minimumWidth(),
                                      self.list_w.minimumHeight()))

        self.spacer_widget = SpacerWidget()
        
        self.list_w.addItem(self.spacer)
        self.list_w.setItemWidget(self.spacer, self.spacer_widget)

        self.layout.addWidget(self.list_w)
        self.layout.addWidget(self.add_btn)
        self.layout.setContentsMargins(1, 1, 1, 1)
        self.layout.setSpacing(0)

        self.setLayout(self.layout)

        self.show()

    def addListItem(self):

        new_label = QListWidgetItem(self.list_w)
        new_label.setSizeHint(QSize(self.list_w.minimumWidth(), 35))

        new_label_widget = ItemWidget()

        self.list_w.addItem(new_label)
        self.list_w.setItemWidget(new_label, new_label_widget)
        self.list_w.scrollToBottom()
        self.itemsinlist += 1
        self.spacer.setSize(self.width(),
                            self.list_w.height() -
                            (self.itemsinlist * 35)-2)

    def resizeEvent(self, event):
        self.spacer.setSizeHint(QSize(self.width(),
                                      self.list_w.height() -
                                      (self.itemsinlist * 35)-2))
        self.list_w.scrollToBottom()


def main():

    app = QApplication(sys.argv)
    wid = Widget()
    sys.exit(app.exec_())


if __name__ == '__main__':
    main()