PyQt:如何设置QTreeView的行高

Question

在PyQt中,我正在寻找一种方法来设置a的行高QTreeView(类似于QTableView.setRowHeight(row, row_height),但QTreeView没有这个函数).QAbstractItemModel用于设置树模型.我在这里阅读了一些建议使用和子类,QAbstractItemDelegate.sizeHint(option, index)但我不知道如何在我的树模型中正确调用它们.

任何最小的代码或建议将不胜感激.谢谢.

Answer 1

根据QTreeView为每个项目返回的数据和大小提示,计算出每行的高度.我想你可能只需要为所有项目或至少第一行(如果有的话setUniformRowHeights(True))返回大小提示.顺便说一句,这可以显着提高性能,所以你应该设置它,如果可以的话.

所以你只需要实现你的AbstractItemModel.data()方法来返回一个大小提示SizeHintRole.像这样的东西:

def data(self, index, role = QtCore.Qt.DisplayRole):
    #  Check the index, possibly return None
    if role == QtCore.Qt.DisplayRole:
        # Return the data
    elif role == QtCore.Qt.SizeHintRole:
        return QtCore.QSize(item_width,item_height)
    # Other roles - maybe return None if you don't use them.

编辑:很好的例子

你说你还有问题所以这里是一个完整的工作示例,基于标准的QT项目视图示例.尝试更改数据方法中返回的QSize以查看视图如何更改:

import sys
from PySide import QtCore,QtGui

class TreeItem(object):
    def __init__(self, data, parent=None):
        self.parentItem = parent
        self.data = data
        self.childItems = []

    def appendChild(self, item):
        self.childItems.append(item)

    def row(self):
        if self.parentItem:
            return self.parentItem.childItems.index(self)
        return 0


class TreeModel(QtCore.QAbstractItemModel):
    def __init__(self, parent=None):
        super(TreeModel, self).__init__(parent)
        self.rootItem = TreeItem(None)
        for i,c in enumerate("abcdefg"):
            child = TreeItem([i,c],self.rootItem)
            self.rootItem.appendChild(child)
        parent = self.rootItem.childItems[1]
        child = TreeItem(["down","down"],parent)
        parent.appendChild(child)

    def columnCount(self, parent):
        return 2

    def data(self, index, role):
        if not index.isValid():
            return None
        if role == QtCore.Qt.DisplayRole:
            item = index.internalPointer()
            return item.data[index.column()]
        elif role == QtCore.Qt.SizeHintRole:
            print "giving size hint"
            return QtCore.QSize(40,40)

        return None


    def flags(self, index):
        if not index.isValid():
            return QtCore.Qt.NoItemFlags
        return QtCore.Qt.ItemIsEnabled | QtCore.Qt.ItemIsSelectable

    def headerData(self, section, orientation, role):
        if orientation == QtCore.Qt.Horizontal and role == QtCore.Qt.DisplayRole:
            return ["A","B"][section]
        return None

    def index(self, row, column, parent):
        if not self.hasIndex(row, column, parent):
            return QtCore.QModelIndex()

        if not parent.isValid():
            parentItem = self.rootItem
        else:
            parentItem = parent.internalPointer()

        childItem = parentItem.childItems[row]
        if childItem:
            return self.createIndex(row, column, childItem)
        else:
            return QtCore.QModelIndex()

    def parent(self, index):
        if not index.isValid():
            return QtCore.QModelIndex()
        parentItem = index.internalPointer().parentItem
        if parentItem == self.rootItem:
            return QtCore.QModelIndex()
        return self.createIndex(parentItem.row(), 0, parentItem)

    def rowCount(self, parent):
        if parent.column() > 0:
            return 0
        if not parent.isValid():
            parentItem = self.rootItem
        else:
            parentItem = parent.internalPointer()
        return len(parentItem.childItems)



if __name__ == '__main__':

    app = QtGui.QApplication(sys.argv)
    model = TreeModel()

    view = QtGui.QTreeView()
    view.setModel(model)
    view.setWindowTitle("Simple Tree Model")
    view.show()
    sys.exit(app.exec_())

Answer 2

使用样式表来做到这一点非常简单：

self.setStyleSheet("QTreeView::item { padding: 10px }")