[Discuss-gnuradio] Using Qt5 widgets in an Embedded Python block

[Barry Duggan]

Hi,

My flowgraph has an Embedded Python block feeding a Throttle feeding a 
Text sink (https://github.com/dl1ksv/gr-display). In my Embedded Python 
block I have a QLineEdit widget and a QTextEdit widget. The user input 
is fed to the output port.

My problem is that I don't know how to tie the widgets to the parent GR. 
I get the following error:
```
Param - Code(_source_code):
	Can't create an instance of your block: arguments did not match any 
overloaded call:
	  QTextEdit(parent: QWidget = None): argument 1 has unexpected type 
'cons_in'
	  QTextEdit(str, parent: QWidget = None): argument 1 has unexpected 
type 'cons_in'
```

Here is my code:
```
"""
Embedded Python Block
"""

#  09/23/2019 Barry Duggan

import numpy as np
from gnuradio import gr
from PyQt5.QtWidgets import (QWidget, QLineEdit, QPushButton,
    QTextEdit, QGridLayout, QApplication)
from PyQt5.QtGui import QCursor
from PyQt5.QtCore import Qt, pyqtSlot

d_buffer = ""
textboxValue = ""

class cons_in (gr.sync_block):

    def __init__(self):
        gr.sync_block.__init__(self,
            name='Console Input',   # will show up in GRC
            in_sig=None,
            out_sig=[np.byte])
        self.initUI()

    def initUI(self):

        # create text display area
        self.textarea = QTextEdit(self)
        self.textarea.setReadOnly(True)

        # create input text area
        self.textbox = QLineEdit(self)
        self.textbox.editingFinished.connect(self.onEnter)
        self.textbox.setFocus()

        grid = QGridLayout()
        grid.setSpacing(10)

        grid.addWidget(self.textarea, 0, 0, 5, 1)
        grid.addWidget(self.textbox, 5, 0)

        self.setLayout(grid)
        self.show()

    def onEnter(self):
        global d_buffer
        global textboxValue

        textboxValue = self.textbox.text()
        d_buffer += (textboxValue + "\n")
        self.textarea.setText(d_buffer)
        self.textbox.setText("")

    def work(self, input_items, output_items):
        global textboxValue

        # <send textboxValue to output port>
        _num_elem = len(textboxValue)
        for x in range (_num_elem):
            output_items[0][x] = textboxValue[x]
        return (_num_elem)
```

A stand-alone version of the code works properly.

Thank you for your help!
--
Barry Duggan