我想知道如何设置QgraphicsView的背景图像。
在此画家程序中，背景仅为白色。
我想加载一些图像（jpg，png，..任何东西）并将其设置为画家的背景。
在绘画之后，我只想保存绘画（不包括背景，仅是我的绘画。）
我该怎么做？请帮助我。
import sys
from PyQt5.QtCore import *
from PyQt5.QtCore import Qt
from PyQt5.QtGui import *
from PyQt5.QtWidgets import *
from PyQt5.QtWidgets import (QApplication, QCheckBox, QGridLayout, QGroupBox,
QPushButton, QVBoxLayout, QWidget, QSlider)
QApplication.setAttribute(Qt.AA_EnableHighDpiScaling, True)
class CWidget(QWidget):
def __init__(self):
super().__init__()
# 전체 폼 박스
formbox = QHBoxLayout()
self.setLayout(formbox)
# 좌, 우 레이아웃박스
left = QVBoxLayout()
right = QVBoxLayout()
# 그룹박스2
gb = QGroupBox('펜 설정')
left.addWidget(gb)
grid = QGridLayout()
gb.setLayout(grid)
label = QLabel('펜 색상')
grid.addWidget(label, 1, 0)
self.pencolor = QColor(0, 0, 0)
self.penbtn = QPushButton()
self.penbtn.setStyleSheet('background-color: rgb(0,0,0)')
self.penbtn.clicked.connect(self.showColorDlg)
grid.addWidget(self.penbtn, 1, 1)
label = QLabel('펜 굵기')
grid.addWidget(label, 2, 0)
self.slider = QSlider(Qt.Horizontal)
self.slider.setMinimum(3)
self.slider.setMaximum(21)
self.slider.setValue(5)
self.slider.setFocusPolicy(Qt.StrongFocus)
self.slider.setTickPosition(QSlider.TicksBothSides)
self.slider.setTickInterval(1)
self.slider.setSingleStep(1)
grid.addWidget(self.slider)
# 그룹박스4
gb = QGroupBox('지우개')
left.addWidget(gb)
hbox = QHBoxLayout()
gb.setLayout(hbox)
self.checkbox = QCheckBox('지우개')
self.checkbox.stateChanged.connect(self.checkClicked)
hbox.addWidget(self.checkbox)
left.addStretch(1)
# 우 레이아웃 박스에 그래픽 뷰 추가
self.view = CView(self)
right.addWidget(self.view)
# 전체 폼박스에 좌우 박스 배치
formbox.addLayout(left)
formbox.addLayout(right)
formbox.setStretchFactor(left, 0)
formbox.setStretchFactor(right, 1)
self.setGeometry(100, 100, 800, 500)
def checkClicked(self):
pass
def createExampleGroup(self):
groupBox = QGroupBox("Slider Example")
slider = QSlider(Qt.Horizontal)
slider.setFocusPolicy(Qt.StrongFocus)
slider.setTickPosition(QSlider.TicksBothSides)
slider.setTickInterval(10)
slider.setSingleStep(1)
vbox = QVBoxLayout()
vbox.addWidget(slider)
vbox.addStretch(1)
groupBox.setLayout(vbox)
return groupBox
def showColorDlg(self):
# 색상 대화상자 생성
color = QColorDialog.getColor()
sender = self.sender()
# 색상이 유효한 값이면 참, QFrame에 색 적용
self.pencolor = color
self.penbtn.setStyleSheet('background-color: {}'.format(color.name()))
# QGraphicsView display QGraphicsScene
class CView(QGraphicsView):
def __init__(self, parent):
super().__init__(parent)
self.scene = QGraphicsScene()
self.setScene(self.scene)
self.items = []
self.start = QPointF()
self.end = QPointF()
self.setRenderHint(QPainter.HighQualityAntialiasing)
def moveEvent(self, e):
rect = QRectF(self.rect())
rect.adjust(0, 0, -2, -2)
self.scene.setSceneRect(rect)
def mousePressEvent(self, e):
if e.button() == Qt.LeftButton:
# 시작점 저장
self.start = e.pos()
self.end = e.pos()
def mouseMoveEvent(self, e):
# e.buttons()는 정수형 값을 리턴, e.button()은 move시 Qt.Nobutton 리턴
if e.buttons() & Qt.LeftButton:
self.end = e.pos()
if self.parent().checkbox.isChecked():
pen = QPen(QColor(255, 255, 255), 10)
path = QPainterPath()
path.moveTo(self.start)
path.lineTo(self.end)
self.scene.addPath(path, pen)
self.start = e.pos()
return None
pen = QPen(self.parent().pencolor, self.parent().slider.value())
# Path 이용
path = QPainterPath()
path.moveTo(self.start)
path.lineTo(self.end)
self.scene.addPath(path, pen)
# 시작점을 다시 기존 끝점으로
self.start = e.pos()
def open(self):
fileName, _ = QFileDialog.getOpenFileName(self, "Open File",
QDir.currentPath())
if fileName:
image = QImage(fileName)
if image.isNull():
QMessageBox.information(self, "Image Viewer",
"Cannot load %s." % fileName)
return
self.imageLabel.setPixmap(QPixmap.fromImage(image))
self.scaleFactor = 1.0
self.printAct.setEnabled(True)
self.fitToWindowAct.setEnabled(True)
self.updateActions()
if not self.fitToWindowAct.isChecked():
self.imageLabel.adjustSize()
if __name__ == '__main__':
app = QApplication(sys.argv)
w = CWidget()
w.show()
sys.exit(app.exec_())
答案 0 :(得分：1)
您可以创建QGraphicsPixmapItem的实例并将其添加到场景中，下面是一个示例：
import sys
from PyQt5.QtCore import *
from PyQt5.QtCore import Qt
from PyQt5.QtGui import *
from PyQt5.QtWidgets import *
from PyQt5.QtWidgets import (QApplication, QCheckBox, QGridLayout, QGroupBox,
QPushButton, QVBoxLayout, QWidget, QSlider)
QApplication.setAttribute(Qt.AA_EnableHighDpiScaling, True)
class CWidget(QWidget):
def __init__(self):
super().__init__()
# 전체 폼 박스
formbox = QHBoxLayout()
self.setLayout(formbox)
# 좌, 우 레이아웃박스
left = QVBoxLayout()
right = QVBoxLayout()
# 그룹박스2
gb = QGroupBox('펜 설정')
left.addWidget(gb)
grid = QGridLayout()
gb.setLayout(grid)
label = QLabel('펜 색상')
grid.addWidget(label, 1, 0)
self.pencolor = QColor(0, 0, 0)
self.penbtn = QPushButton()
self.penbtn.setStyleSheet('background-color: rgb(0,0,0)')
self.penbtn.clicked.connect(self.showColorDlg)
grid.addWidget(self.penbtn, 1, 1)
label = QLabel('펜 굵기')
grid.addWidget(label, 2, 0)
self.slider = QSlider(Qt.Horizontal)
self.slider.setMinimum(3)
self.slider.setMaximum(21)
self.slider.setValue(5)
self.slider.setFocusPolicy(Qt.StrongFocus)
self.slider.setTickPosition(QSlider.TicksBothSides)
self.slider.setTickInterval(1)
self.slider.setSingleStep(1)
grid.addWidget(self.slider)
# 그룹박스4
gb = QGroupBox('지우개')
left.addWidget(gb)
hbox = QHBoxLayout()
gb.setLayout(hbox)
self.checkbox = QCheckBox('지우개')
self.checkbox.stateChanged.connect(self.checkClicked)
hbox.addWidget(self.checkbox)
left.addStretch(1)
# 우 레이아웃 박스에 그래픽 뷰 추가
self.view = CView(self)
right.addWidget(self.view)
# 전체 폼박스에 좌우 박스 배치
formbox.addLayout(left)
formbox.addLayout(right)
formbox.setStretchFactor(left, 0)
formbox.setStretchFactor(right, 1)
self.setGeometry(100, 100, 800, 500)
def checkClicked(self, state):
self.view.stretch(state)
def createExampleGroup(self):
groupBox = QGroupBox("Slider Example")
slider = QSlider(Qt.Horizontal)
slider.setFocusPolicy(Qt.StrongFocus)
slider.setTickPosition(QSlider.TicksBothSides)
slider.setTickInterval(10)
slider.setSingleStep(1)
vbox = QVBoxLayout()
vbox.addWidget(slider)
vbox.addStretch(1)
groupBox.setLayout(vbox)
return groupBox
def showColorDlg(self):
# 색상 대화상자 생성
color = QColorDialog.getColor()
sender = self.sender()
# 색상이 유효한 값이면 참, QFrame에 색 적용
self.pencolor = color
self.penbtn.setStyleSheet('background-color: {}'.format(color.name()))
# QGraphicsView display QGraphicsScene
class CView(QGraphicsView):
def __init__(self, parent):
super().__init__(parent)
self.scene = QGraphicsScene()
self.setScene(self.scene)
self.items = []
self.start = QPointF()
self.end = QPointF()
self.backgroundImage = None
self.graphicsPixmapItem = None
self.setRenderHint(QPainter.HighQualityAntialiasing)
self.open()
def moveEvent(self, e):
rect = QRectF(self.rect())
rect.adjust(0, 0, -2, -2)
self.scene.setSceneRect(rect)
def mousePressEvent(self, e):
if e.button() == Qt.LeftButton:
# 시작점 저장
self.start = e.pos()
self.end = e.pos()
def mouseMoveEvent(self, e):
# e.buttons()는 정수형 값을 리턴, e.button()은 move시 Qt.Nobutton 리턴
if e.buttons() & Qt.LeftButton:
self.end = e.pos()
if self.parent().checkbox.isChecked():
pen = QPen(QColor(255, 255, 255), 10)
path = QPainterPath()
path.moveTo(self.start)
path.lineTo(self.end)
self.scene.addPath(path, pen)
self.start = e.pos()
return None
pen = QPen(self.parent().pencolor, self.parent().slider.value())
# Path 이용
path = QPainterPath()
path.moveTo(self.start)
path.lineTo(self.end)
self.scene.addPath(path, pen)
# 시작점을 다시 기존 끝점으로
self.start = e.pos()
def stretch(self, state):
self._set_image(state == 2)
def open(self):
fileName, _ = QFileDialog.getOpenFileName(self, "Open File", QDir.currentPath(), filter='Images (*.png *.xpm *.jpg)')
if fileName:
image = QImage(fileName)
if image.isNull():
QMessageBox.information(self, "Image Viewer",
"Cannot load %s." % fileName)
return
self.backgroundImage = fileName
self._set_image(False)
def _set_image(self, stretch: bool):
tempImg = QPixmap(self.backgroundImage)
if stretch:
tempImg = tempImg.scaled(self.scene.width(), self.scene.height())
if self.graphicsPixmapItem is not None:
self.scene.removeItem(self.graphicsPixmapItem)
self.graphicsPixmapItem = QGraphicsPixmapItem(tempImg)
self.scene.addItem(self.graphicsPixmapItem)
if __name__ == '__main__':
app = QApplication(sys.argv)
w = CWidget()
w.show()
sys.exit(app.exec_())