sharedmemory.py 文件源码

def loadFromMemory(self):
        """ This slot function is called in the second Dialog process, when the
        user presses the "Load Image from Shared Memory" button.  First, it
        attaches the process to the shared memory segment created by the first
        Dialog process.  Then it locks the segment for exclusive access, copies
        the image data from the segment into a QBuffer, and streams the QBuffer
        into a QImage.  Then it unlocks the shared memory segment, detaches
        from it, and finally displays the QImage in the Dialog.
        """

        if not self.sharedMemory.attach():
            self.ui.label.setText(
                    "Unable to attach to shared memory segment.\nLoad an "
                    "image first.")
            return

        buf = QBuffer()
        ins = QDataStream(buf)
        image = QImage()

        self.sharedMemory.lock()
        buf.setData(self.sharedMemory.constData())
        buf.open(QBuffer.ReadOnly)
        ins >> image
        self.sharedMemory.unlock()
        self.sharedMemory.detach()

        self.ui.label.setPixmap(QPixmap.fromImage(image))