如何更改 QTableView 图像大小

Question

模型的data() 正确地为每个QModelIndex 分配了一个缩放为64x64 的像素图。但是猴子被剪掉了，因为行的高度太短了。 下面的两行仅调整第二行的大小（为什么只有第二行？！）：

    self.tableviewA.resizeColumnToContents(True)
    self.tableviewA.resizeRowToContents(True)

当然，我可以手动迭代每一行和setRowHeight(row, heightInt)。但这将是机器执行的额外计算。我想知道是否有更好更简单的方法让QTableView 调整每一行的大小以适应拇指（或任何其他上下文）填充它...

这是运行下面发布的示例代码所需的猴子图标的链接（右键单击以将其另存为“monkey.png”到运行脚本的同一文件夹）：

from PyQt4.QtCore import *
from PyQt4.QtGui import *
import sys, os

class Model(QAbstractTableModel):
    def __init__(self, parent=None, *args):
        QAbstractTableModel.__init__(self, parent, *args)
        self.images = ['monkey.png','monkey.png','monkey.png']
        self.items = ['Row0_Column0','Row0_Column1','Row0_Column2']

        self.thumbSize=64

    def resizePixmap(self, mult):
        self.thumbSize=self.thumbSize*mult
        self.reset()

    def flags(self, index):
        return Qt.ItemIsEnabled | Qt.ItemIsSelectable | Qt.ItemIsEditable

    def rowCount(self, parent):
        return len(self.items)       
    def columnCount(self, parent):
        return 3

    def data(self, index, role):
        if not index.isValid(): return QVariant()
        row=index.row()
        if row>len(self.items): return QVariant()

        if role == Qt.DisplayRole:
            return QVariant(self.items[row])

        elif role == Qt.DecorationRole:

            image=self.images[row]
            pixmap=QPixmap(image).scaled(QSize(self.thumbSize, self.thumbSize), Qt.KeepAspectRatio)
            return pixmap

        return QVariant()

    def setData(self, index, value, role=Qt.EditRole):
        if index.isValid():            
            if role == Qt.EditRole:                
                row = index.row()
                self.items[row]=value  
                return True
        return False

class MyWindow(QWidget):
    def __init__(self, *args):
        QWidget.__init__(self, *args)

        self.tablemodel=Model(self)               

        self.tableviewA=QTableView() 
        self.tableviewA.setModel(self.tablemodel)   

        buttonPlus=QPushButton('Plus')
        buttonMinus=QPushButton('Minus') 

        buttonPlus.clicked.connect(self.plus)
        buttonMinus.clicked.connect(self.minus)

        layout = QVBoxLayout(self)
        layout.addWidget(self.tableviewA)
        layout.addWidget(buttonPlus)
        layout.addWidget(buttonMinus)
        self.setLayout(layout)

        self.tableviewA.resizeColumnToContents(True)
        self.tableviewA.resizeRowToContents(True)

    def plus(self, arg):
        self.tablemodel.resizePixmap(1.1)

        thumbSize=self.tableviewA.model().thumbSize 
        totalRows=self.tablemodel.rowCount(QModelIndex())
        for row in range(totalRows):
            self.tableviewA.setRowHeight(row, thumbSize*1.1)

    def minus(self, arg):
        self.tablemodel.resizePixmap(0.9)

        thumbSize=self.tableviewA.model().thumbSize 
        totalRows=self.tablemodel.rowCount(QModelIndex())
        for row in range(totalRows):
            self.tableviewA.setRowHeight(row, thumbSize*0.9)


if __name__ == "__main__":
    app = QApplication(sys.argv)
    w = MyWindow()
    w.show()
    sys.exit(app.exec_())

Answer 1

问题在于没有使用

self.tableviewA.resizeRowsToContents()
self.tableviewA.resizeColumnsToContents()

分别重置行高和列宽的方法。 在下面发布的解决方案中，我也包含了一个elif role == Qt.SizeHintRole:...（此处用于教育目的）。

from PyQt4.QtCore import *
from PyQt4.QtGui import *
import sys, os

class Model(QAbstractTableModel):
    def __init__(self, parent=None, *args):
        QAbstractTableModel.__init__(self, parent, *args)
        self.images = ['monkey.png','monkey.png','monkey.png']
        self.items = ['Row0_Column0','Row0_Column1','Row0_Column2']

        self.thumbSize=64

    def resizePixmap(self, mult):
        self.thumbSize=self.thumbSize*mult
        self.reset()

    def flags(self, index):
        return Qt.ItemIsEnabled | Qt.ItemIsSelectable | Qt.ItemIsEditable

    def rowCount(self, parent):
        return len(self.items)       
    def columnCount(self, parent):
        return 3

    def data(self, index, role):
        if not index.isValid(): return QVariant()
        row=index.row()
        if row>len(self.items): return QVariant()

        if role == Qt.DisplayRole:
            return QVariant(self.items[row])

        elif role == Qt.DecorationRole:
            image=self.images[row]
            pixmap=QPixmap(image).scaled(QSize(self.thumbSize, self.thumbSize), Qt.KeepAspectRatio)
            return pixmap

        elif role == Qt.SizeHintRole:
            print 'Model.data(role == Qt.SizeHintRole) row: %s; column %s'%(index.row(), index.column())
            # return QSize(32, 32)

        return QVariant()

    def setData(self, index, value, role=Qt.EditRole):
        if index.isValid():            
            if role == Qt.EditRole:                
                row = index.row()
                self.items[row]=value  
                return True
        return False


class MyWindow(QWidget):
    def __init__(self, *args):
        QWidget.__init__(self, *args)

        self.tablemodel=Model(self)               

        self.tableviewA=QTableView() 
        self.tableviewA.setModel(self.tablemodel)   

        buttonResize=QPushButton('Resize')
        buttonZoomIn=QPushButton('Zoom In')
        buttonZoomOut=QPushButton('Zoom Out') 

        buttonResize.clicked.connect(self.resizeView)
        buttonZoomIn.clicked.connect(self.zoomIn)
        buttonZoomOut.clicked.connect(self.zoomOut)

        layout = QVBoxLayout(self)
        layout.addWidget(self.tableviewA)
        layout.addWidget(buttonResize)
        layout.addWidget(buttonZoomIn)
        layout.addWidget(buttonZoomOut)

        self.setLayout(layout)

        # self.tableviewA.resizeRowsToContents()
        # self.tableviewA.resizeColumnsToContents()

    def zoomIn(self, arg):
        self.tablemodel.resizePixmap(1.1)
        self.resizeView()

    def zoomOut(self, arg):
        self.tablemodel.resizePixmap(0.9)
        self.resizeView()

    def resizeView(self):
        self.tableviewA.resizeRowsToContents()
        self.tableviewA.resizeColumnsToContents()       

if __name__ == "__main__":
    app = QApplication(sys.argv)
    w = MyWindow()
    w.show()
    sys.exit(app.exec_())