That hasImage()
returns True does not imply that imageData()
returns a QImage since it only indicates that the user copied an image to the clipboard, and in what format do I copy the image? Well, it could be png, jpg, etc or it could provide the url for the client application to download or html to insert it into the client application and then obtain the image by rendering the HTML.
So in general the application from which the image was copied is responsible for the sending format and that there is no restrictive standard for that format but there are common formats.
The following example shows the logic to handle the images that come from urls and HTML:
#!/usr/bin/python
import sys
from functools import cached_property
from PyQt5.QtCore import pyqtSignal, QObject, QUrl
from PyQt5.QtNetwork import QNetworkAccessManager, QNetworkRequest, QNetworkReply
from PyQt5.QtGui import QGuiApplication, QImage, QPixmap
from PyQt5.QtWidgets import QApplication, QWidget, QLabel
from bs4 import BeautifulSoup
class ImageDownloader(QObject):
finished = pyqtSignal(QImage)
def __init__(self, parent=None):
super().__init__(parent)
self.manager.finished.connect(self.handle_finished)
@cached_property
def manager(self):
return QNetworkAccessManager()
def start_download(self, url):
self.manager.get(QNetworkRequest(url))
def handle_finished(self, reply):
if reply.error() != QNetworkReply.NoError:
print("error: ", reply.errorString())
return
image = QImage()
image.loadFromData(reply.readAll())
self.finished.emit(image)
class ClipboardManager(QObject):
imageChanged = pyqtSignal(QImage)
def __init__(self, parent=None):
super().__init__(parent)
QGuiApplication.clipboard().dataChanged.connect(
self.handle_clipboard_datachanged
)
self.downloader.finished.connect(self.imageChanged)
@cached_property
def downloader(self):
return ImageDownloader()
def handle_clipboard_datachanged(self):
mime = QGuiApplication.clipboard().mimeData()
if mime.hasImage():
image = mime.imageData()
if image is not None:
self.imageChanged.emit(image)
elif mime.hasUrls():
url = mime.urls()[0]
self.downloader.start_download(urls[0])
elif mime.hasHtml():
html = mime.html()
soup = BeautifulSoup(html, features="lxml")
imgs = soup.findAll("img")
if imgs:
url = QUrl.fromUserInput(imgs[0]["src"])
self.downloader.start_download(url)
else:
for fmt in mime.formats():
print(fmt, mime.data(fmt))
def main():
app = QApplication(sys.argv)
label = QLabel(scaledContents=True)
label.resize(250, 150)
label.move(300, 300)
label.setWindowTitle("Simple")
label.show()
manager = ClipboardManager()
manager.imageChanged.connect(
lambda image: label.setPixmap(QPixmap.fromImage(image))
)
sys.exit(app.exec_())
if __name__ == "__main__":
main()
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