contents_scale_test - GitPress.io

Example Python program contents_scale_test.py This program creates a PyQt GUI

Modules

from PyQt5.QtGui import QPainter
from PyQt5.QtCore import *
from PyQt5.QtQuick import *
from PyQt5.QtWidgets import *
import sys

Classes

class Item(QQuickPaintedItem):
class Window(QMainWindow):

Methods

def init(self, useBoundRect, parent=None):
def getBoundRect(self):
def paint(self, painter):
def init(self, parent=None):
def add_item(self, useBoundRect, x, y, w, h, ss, cw, ch, cs, col):

Code

Example Python PyQt program :

#!/usr/bin/env python3

from PyQt5.QtGui import QPainter
from PyQt5.QtCore import *
from PyQt5.QtQuick import *
from PyQt5.QtWidgets import *

class Item(QQuickPaintedItem):
    def __init__(self, useBoundRect, parent=None):
        super().__init__(parent)
        self._ubr = useBoundRect

    def getBoundRect(self):
        if self._ubr:
            return self.contentsBoundingRect()
        else:
            return QRectF(0, 0, self.width(), self.height())

    def paint(self, painter):
        br = self.getBoundRect()
        font = painter.font()
        painter.drawText(br, Qt.TextWordWrap | Qt.AlignCenter, 'Hello, cruel world!')

class Window(QMainWindow):
    def __init__(self, parent=None):
        super().__init__(parent)
        self._win = QQuickWindow()
        self._cont = QWidget.createWindowContainer(self._win)
        self._items = []
        self.setCentralWidget(self._cont)
        self.resize(420, 400)

    def add_item(self, useBoundRect, x, y, w, h, ss, cw, ch, cs, col):
        root = self._win.contentItem()
        it = Item(useBoundRect, root)
        it.setX(x)
        it.setY(y)
        it.setScale(ss)
        it.setWidth(w)
        it.setHeight(h)
        it.setContentsScale(cs)
        it.setContentsSize(QSize(cw, ch))
        it.setFillColor(col)
        self._items.append(it)
        return it

if __name__ == '__main__':
    import sys
    app = QApplication(sys.argv)
    win = Window()
    win.show()
    # First and second rows: painting uses contentsBoundingRect()
    # First row: just use item's scale. Content is low-res, but scaled
    #           BoRect,   x    y    w   h  scale cw  ch  cscale, color
    win.add_item(True,   10,  10, 100, 50,   1,   -1, -1,   1, Qt.green)
    win.add_item(True,  150,  20, 100, 50, 1.5,   -1, -1,   1, Qt.yellow)
    win.add_item(True,  275,  10, 100, 50, 0.5,   -1, -1,   1, Qt.yellow)
    # Second row: scale the contents instead of the item
    #           BoRect,   x    y    w   h  scale cw  ch  cscale, color
    win.add_item(True,  10,  100,   1,  1,   1,  100, 50,   1, Qt.red)
    win.add_item(True,  125, 100,   1,  1,   1,  100, 50, 1.5, Qt.magenta)
    win.add_item(True,  300, 100,   1,  1,   1,   50, 25, 0.5, Qt.magenta)

    # Third and fourth rows: painting uses width() and height()
    # Third row: scale the item, same result as before
    win.add_item(False,  10, 210, 100, 50,   1,   -1, -1,   1, Qt.darkGreen)
    win.add_item(False, 150, 220, 100, 50, 1.5,   -1, -1,   1, Qt.darkYellow)
    win.add_item(False, 275, 220, 100, 50, 0.5,   -1, -1,   1, Qt.darkYellow)
    # Fourth row: scale the content
    win.add_item(False,  10, 300, 100, 50,   1,  100, 50,   1, Qt.darkRed)
    win.add_item(False, 125, 300, 100, 50,   1,  100, 50, 1.5, Qt.darkMagenta)
    win.add_item(False, 300, 300, 100, 50,   1,   50, 25, 0.5, Qt.darkMagenta)
    #           BoRect,   x    y    w   h  scale cw  ch  cscale, color

    sys.exit(app.exec_())

Useful Links

Articles: https://python-commandments.org/
PyQt: https://pythonpyqt.com/
Tutorial: https://pythonprogramminglanguage.com/