How to use rubber band to zoom in and out in pyqt5 - python-3.x

Question

I would like to use the RubberBand to zoom in and out relative to the size of the box I would like to zoom in the view to fit whatever is inside the block to the full view.
Can anyone help?
The zoom in and out with the mouse works as expected.
You can see in the code the rubberband works but I don't know how to make the zoom relative to the size of the box.
code:
from PyQt5.QtCore import *
from PyQt5.QtGui import *
from PyQt5.QtWidgets import *
import sys
from math import sqrt
class Point(QGraphicsItem):
def __init__(self, x, y):
super(Point, self).__init__()
self.setFlag(QGraphicsItem.ItemIsSelectable, True)
self.rectF = QRectF(0, 0, 30, 30)
self.x=x
self.y=y
self._brush = QBrush(Qt.black)
def setBrush(self, brush):
self._brush = brush
self.update()
def boundingRect(self):
return self.rectF
def paint(self, painter=None, style=None, widget=None):
painter.fillRect(self.rectF, self._brush)
def hoverMoveEvent(self, event):
point = event.pos().toPoint()
print(point)
QGraphicsItem.hoverMoveEvent(self, event)
class Viewer(QGraphicsView):
photoClicked = pyqtSignal(QPoint)
rectChanged = pyqtSignal(QRect)
def __init__(self, parent):
super(Viewer, self).__init__(parent)
self.rubberBand = QRubberBand(QRubberBand.Rectangle, self)
self.setMouseTracking(True)
self.origin = QPoint()
self.changeRubberBand = False
self._zoom = 0
self._empty = True
self._scene = QGraphicsScene(self)
self.setTransformationAnchor(QGraphicsView.AnchorUnderMouse)
self.setResizeAnchor(QGraphicsView.AnchorUnderMouse)
self.setVerticalScrollBarPolicy(Qt.ScrollBarAlwaysOff)
self.setHorizontalScrollBarPolicy(Qt.ScrollBarAlwaysOff)
self.setFrameShape(QFrame.NoFrame)
self.area = float()
self.setPoints()
def setItems(self):
self.data = {'x': [-2414943.8686, -2417160.6592, -2417160.6592, -2417856.1783, -2417054.7618, -2416009.9966, -2416012.5232, -2418160.8952, -2418160.8952, -2416012.5232, -2417094.7694, -2417094.7694], 'y': [10454269.7008,
10454147.2672, 10454147.2672, 10453285.2456, 10452556.8132, 10453240.2808, 10455255.8752, 10455183.1912, 10455183.1912, 10455255.8752, 10456212.5959, 10456212.5959]}
maxX = max(self.data['x'])
minX = min(self.data['x'])
maxY = max(self.data['y'])
minY = min(self.data['y'])
distance = sqrt((maxX-minX)**2+(maxY-minY)**2)
self.area = QRectF(minX, minY, distance, distance)
for i,x in enumerate(self.data['x']):
x = self.data['x'][i]
y = self.data['y'][i]
p = Point(x,y)
p.setPos(x,y)
self._scene.addItem(p)
self.setScene(self._scene)
def fitInView(self, scale=True):
rect = QRectF(self.area)
if not rect.isNull():
self.setSceneRect(rect)
unity = self.transform().mapRect(QRectF(0, 0, 1, 1))
self.scale(1 / unity.width(), 1 / unity.height())
viewrect = self.viewport().rect()
scenerect = self.transform().mapRect(rect)
factor = min(viewrect.width() / scenerect.width(),
viewrect.height() / scenerect.height())
self.scale(factor, factor)
self._zoom = 0
def setPoints(self):
self._zoom = 0
self.setItems()
self.setDragMode(True)
self.fitInView()
def wheelEvent(self, event):
if event.angleDelta().y() > 0:
factor = 1.25
self._zoom += 1
else:
factor = 0.8
self._zoom -= 1
if self._zoom > 0:
self.scale(factor, factor)
elif self._zoom == 0:
self.fitInView()
else:
self._zoom = 0
def mousePressEvent(self, event):
if event.button() == Qt.LeftButton:
self.origin = event.pos()
self.rubberBand.setGeometry(QRect(self.origin, QSize()))
self.rectChanged.emit(self.rubberBand.geometry())
self.rubberBand.show()
self.changeRubberBand = True
return
#QGraphicsView.mousePressEvent(self,event)
elif event.button() == Qt.MidButton:
self.viewport().setCursor(Qt.ClosedHandCursor)
self.original_event = event
handmade_event = QMouseEvent(QEvent.MouseButtonPress,QPointF(event.pos()),Qt.LeftButton,event.buttons(),Qt.KeyboardModifiers())
QGraphicsView.mousePressEvent(self,handmade_event)
super(Viewer, self).mousePressEvent(event)
def mouseReleaseEvent(self, event):
if event.button() == Qt.LeftButton:
self.origin = event.pos()
self.rubberBand.setGeometry(QRect(self.origin, QSize()))
self.changeRubberBand = False
QGraphicsView.mouseReleaseEvent(self,event)
elif event.button() == Qt.MidButton:
self.viewport().setCursor(Qt.OpenHandCursor)
handmade_event = QMouseEvent(QEvent.MouseButtonRelease,QPointF(event.pos()),Qt.LeftButton,event.buttons(),Qt.KeyboardModifiers())
QGraphicsView.mouseReleaseEvent(self,handmade_event)
super(Viewer, self).mouseReleaseEvent(event)
def mouseMoveEvent(self, event):
if self.changeRubberBand:
self.rubberBand.setGeometry(QRect(self.origin, event.pos()).normalized())
self.rectChanged.emit(self.rubberBand.geometry())
QGraphicsView.mouseMoveEvent(self,event)
super(Viewer, self).mouseMoveEvent(event)
class Window(QWidget):
def __init__(self):
super(Window, self).__init__()
self.viewer = Viewer(self)
self.btnLoad = QToolButton(self)
self.btnLoad.setText('Load Points')
self.btnLoad.clicked.connect(self.loadPoints)
VBlayout = QVBoxLayout(self)
VBlayout.addWidget(self.viewer)
HBlayout = QHBoxLayout()
HBlayout.setAlignment(Qt.AlignLeft)
HBlayout.addWidget(self.btnLoad)
VBlayout.addLayout(HBlayout)
def loadPoints(self):
self.viewer.setPoints()
if __name__ == '__main__':
import sys
app = QApplication(sys.argv)
window = Window()
window.setGeometry(500, 300, 800, 600)
window.show()
sys.exit(app.exec_())