Anchor Layout Example¶
This application demonstrates the use of QGraphicsAnchorLayout in a PySide6 Widget application. It creates a graphical scene with several QPushButton widgets arranged using anchor constraints, allowing for dynamic and flexible layout management within a QGraphicsView. It demonstrates the analogous Qt example Anchor Layout Example
# Copyright (C) 2013 Riverbank Computing Limited.
# Copyright (C) 2022 The Qt Company Ltd.
# SPDX-License-Identifier: LicenseRef-Qt-Commercial OR BSD-3-Clause
from __future__ import annotations
import sys
from PySide6.QtCore import QSizeF, Qt
from PySide6.QtWidgets import (QApplication, QGraphicsAnchorLayout,
QGraphicsProxyWidget, QGraphicsScene,
QGraphicsView, QGraphicsWidget,
QPushButton, QSizePolicy)
def create_item(minimum, preferred, maximum, name):
w = QGraphicsProxyWidget()
w.setWidget(QPushButton(name))
w.setMinimumSize(minimum)
w.setPreferredSize(preferred)
w.setMaximumSize(maximum)
w.setSizePolicy(QSizePolicy.Policy.Preferred, QSizePolicy.Policy.Preferred)
return w
if __name__ == '__main__':
app = QApplication(sys.argv)
scene = QGraphicsScene()
scene.setSceneRect(0, 0, 800, 480)
min_size = QSizeF(30, 100)
pref_size = QSizeF(210, 100)
max_size = QSizeF(300, 100)
a = create_item(min_size, pref_size, max_size, "A")
b = create_item(min_size, pref_size, max_size, "B")
c = create_item(min_size, pref_size, max_size, "C")
d = create_item(min_size, pref_size, max_size, "D")
e = create_item(min_size, pref_size, max_size, "E")
f = create_item(QSizeF(30, 50), QSizeF(150, 50), max_size, "F")
g = create_item(QSizeF(30, 50), QSizeF(30, 100), max_size, "G")
l = QGraphicsAnchorLayout() # noqa: E741
l.setSpacing(0)
w = QGraphicsWidget(None, Qt.WindowType.Window)
w.setPos(20, 20)
w.setLayout(l)
# Vertical
l.addAnchor(a, Qt.AnchorPoint.AnchorTop, l, Qt.AnchorPoint.AnchorTop)
l.addAnchor(b, Qt.AnchorPoint.AnchorTop, l, Qt.AnchorPoint.AnchorTop)
l.addAnchor(c, Qt.AnchorPoint.AnchorTop, a, Qt.AnchorPoint.AnchorBottom)
l.addAnchor(c, Qt.AnchorPoint.AnchorTop, b, Qt.AnchorPoint.AnchorBottom)
l.addAnchor(c, Qt.AnchorPoint.AnchorBottom, d, Qt.AnchorPoint.AnchorTop)
l.addAnchor(c, Qt.AnchorPoint.AnchorBottom, e, Qt.AnchorPoint.AnchorTop)
l.addAnchor(d, Qt.AnchorPoint.AnchorBottom, l, Qt.AnchorPoint.AnchorBottom)
l.addAnchor(e, Qt.AnchorPoint.AnchorBottom, l, Qt.AnchorPoint.AnchorBottom)
l.addAnchor(c, Qt.AnchorPoint.AnchorTop, f, Qt.AnchorPoint.AnchorTop)
l.addAnchor(c, Qt.AnchorPoint.AnchorVerticalCenter, f, Qt.AnchorPoint.AnchorBottom)
l.addAnchor(f, Qt.AnchorPoint.AnchorBottom, g, Qt.AnchorPoint.AnchorTop)
l.addAnchor(c, Qt.AnchorPoint.AnchorBottom, g, Qt.AnchorPoint.AnchorBottom)
# Horizontal.
l.addAnchor(l, Qt.AnchorPoint.AnchorLeft, a, Qt.AnchorPoint.AnchorLeft)
l.addAnchor(l, Qt.AnchorPoint.AnchorLeft, d, Qt.AnchorPoint.AnchorLeft)
l.addAnchor(a, Qt.AnchorPoint.AnchorRight, b, Qt.AnchorPoint.AnchorLeft)
l.addAnchor(a, Qt.AnchorPoint.AnchorRight, c, Qt.AnchorPoint.AnchorLeft)
l.addAnchor(c, Qt.AnchorPoint.AnchorRight, e, Qt.AnchorPoint.AnchorLeft)
l.addAnchor(b, Qt.AnchorPoint.AnchorRight, l, Qt.AnchorPoint.AnchorRight)
l.addAnchor(e, Qt.AnchorPoint.AnchorRight, l, Qt.AnchorPoint.AnchorRight)
l.addAnchor(d, Qt.AnchorPoint.AnchorRight, e, Qt.AnchorPoint.AnchorLeft)
l.addAnchor(l, Qt.AnchorPoint.AnchorLeft, f, Qt.AnchorPoint.AnchorLeft)
l.addAnchor(l, Qt.AnchorPoint.AnchorLeft, g, Qt.AnchorPoint.AnchorLeft)
l.addAnchor(f, Qt.AnchorPoint.AnchorRight, g, Qt.AnchorPoint.AnchorRight)
scene.addItem(w)
scene.setBackgroundBrush(Qt.GlobalColor.darkGreen)
view = QGraphicsView(scene)
view.show()
sys.exit(app.exec())