I am planning to make a small photo cropping software and I encounter this problem where when I moved the QRubberband
I made, it is kind of moving past to the borders of the QLabel
.
Here is the sample code: (Left-click and drag to make a QRubberband
and Right-click to move the QRubberband
)
import sys
from PyQt5.QtGui import *
from PyQt5.QtCore import *
from PyQt5.QtWidgets import *
class ResizableRubberBand(QWidget):
def __init__(self, parent=None):
super(ResizableRubberBand, self).__init__(parent)
self.draggable = True
self.dragging_threshold = 5
self.mousePressPos = None
self.mouseMovePos = None
self.borderRadius = 5
self.setWindowFlags(Qt.SubWindow)
layout = QHBoxLayout(self)
layout.setContentsMargins(0, 0, 0, 0)
layout.addWidget(
QSizeGrip(self), 0,
Qt.AlignLeft | Qt.AlignTop)
layout.addWidget(
QSizeGrip(self), 0,
Qt.AlignRight | Qt.AlignBottom)
self._band = QRubberBand(
QRubberBand.Rectangle, self)
self._band.show()
self.show()
def resizeEvent(self, event):
self._band.resize(self.size())
def paintEvent(self, event):
# Get current window size
window_size = self.size()
qp = QPainter()
qp.begin(self)
qp.setRenderHint(QPainter.Antialiasing, True)
qp.drawRoundedRect(0, 0, window_size.width(), window_size.height(),
self.borderRadius, self.borderRadius)
qp.end()
def mousePressEvent(self, event):
if self.draggable and event.button() == Qt.RightButton:
self.mousePressPos = event.globalPos() # global
self.mouseMovePos = event.globalPos() - self.pos() # local
super(ResizableRubberBand, self).mousePressEvent(event)
def mouseMoveEvent(self, event):
if self.draggable and event.buttons() & Qt.RightButton:
globalPos = event.globalPos()
moved = globalPos - self.mousePressPos
if moved.manhattanLength() > self.dragging_threshold:
# Move when user drag window more than dragging_threshold
diff = globalPos - self.mouseMovePos
self.move(diff)
self.mouseMovePos = globalPos - self.pos()
super(ResizableRubberBand, self).mouseMoveEvent(event)
def mouseReleaseEvent(self, event):
if self.mousePressPos is not None:
if event.button() == Qt.RightButton:
moved = event.globalPos() - self.mousePressPos
if moved.manhattanLength() > self.dragging_threshold:
# Do not call click event or so on
event.ignore()
self.mousePressPos = None
super(ResizableRubberBand, self).mouseReleaseEvent(event)
class mQLabel(QLabel):
def __init__(self, parent=None):
QLabel.__init__(self, parent)
self.setContentsMargins(0,0,0,0)
self.setAlignment(Qt.AlignTop | Qt.AlignLeft)
self.setSizePolicy(QSizePolicy.MinimumExpanding, QSizePolicy.MinimumExpanding)
def mousePressEvent(self, event):
if event.button() == Qt.LeftButton: #and (hasattr(self, 'bla')):
self.first_mouse_location = (event.x(), event.y())
self.band = ResizableRubberBand(self)
self.band.setGeometry(event.x(), event.y(), 0, 0)
def mouseMoveEvent(self, event):
if event.buttons() & Qt.LeftButton:
first_mouse_location_x = self.first_mouse_location[0]
first_mouse_location_y = self.first_mouse_location[1]
new_x, new_y = event.x(), event.y()
difference_x = new_x - first_mouse_location_x
difference_y = new_y - first_mouse_location_y
self.band.resize(difference_x, difference_y)
class App(QWidget):
def __init__(self):
super().__init__()
## Set main window attributes
self.setFixedSize(1000,600)
# Add Label
self.label = mQLabel()
self.label.setStyleSheet("border: 1px solid black;")
self.label_layout = QHBoxLayout(self)
self.label_layout.addWidget(self.label)
self.show()
if __name__ == '__main__':
app = QApplication(sys.argv)
ex = App()
sys.exit(app.exec_())
I can't really think of a simple solution where I can do it. My first instinct is to get the size of the parent, but I don't know what should I do next.