Customizing List View Items

Challenge: Fill in the gaps in the code.

Subclassing QListViewItem

To draw custom list view items, we need to subclass QListViewItem:

from qt import QBrush, QFont, QFontMetrics, QListViewItem, QPen, Qt 

class ListViewItem(QListViewItem):

    normal_brush = QBrush(Qt.white)
    highlighted_brush = QBrush(Qt.white)
    normal_pen = QPen(Qt.black)
    highlighted_pen = QPen(Qt.red)

    def __init__(self, key, *args):
    
        QListViewItem.__init__(self,  *args)
        self.pen = self.normal_pen
        self.brush = self.normal_brush

Painting

The paintCell method allow us to draw the list view items in our preferred style. We can always use the QListViewItem base class to draw anything we are unsure about:

   def paintCell(self, painter, colour_group, column, width, alignment): 
    
        if self.isSelected():
            QListViewItem.paintCell(self, painter, colour_group, column, width, alignment)
        else:
            painter.save()
            painter.fillRect(0, 0, width, self.height(), self.brush)
            painter.setFont(self.fonts[column])
            painter.setPen(self.pen)
            painter.drawText(0, QFontMetrics(self.fonts[column]).ascent(), self.text(column))
            painter.restore()

Highlighting items

We can highlight the text in a particular column by calling a custom method. This just changes the pen and brush colours for the text in that column:

   def setHighlighted(self, column, enable): 
    
        if enable:
            self.pen = self.highlighted_pen
            self.brush = self.highlighted_brush
        else:
            self.pen = self.normal_pen
            self.brush = self.normal_brush
        
        self.listView().triggerUpdate()

Other issues

The font needs to be set for the text in any new columns that are created:

   def setText(self, column, text): 
    
        while column >= len(self.fonts):
        
            font = QFont()
            self.fonts.append(font)
        
        QListViewItem.setText(self, column, text)