Python Qt5 : Add and remove items between two QTreeWidgets.

Today's tutorial will show you how to add and remove items between two QTreeWidgets.
The source code is very simple to understand: the user interface is created with two QTreeWidgets.
One is completed with elements and when the buttons are pressed, the elements are interchanged.

import sys
from PyQt5.QtWidgets import QApplication, QWidget, QDesktopWidget, QPushButton
from PyQt5.QtWidgets import QBoxLayout,QTreeWidget,QTreeWidgetItem

class my_app_class(QWidget):
    def __init__(self):
        super().__init__()

        self.add_button=QPushButton('Add item here')
        self.remove_button=QPushButton('Remove item')
        self.wishlist=QTreeWidget(self)
        self.tree_list=QTreeWidget(self)
        # init the UI
        self.initUI()

    def initUI(self):
        # set title of window
        self.setWindowTitle('add and remove items from QTreeWidget!')

        self.init_tree()

        self.resize(800, 480)
        self.center()
        self.show()

    def center(self):
        geometry_frame = self.frameGeometry()
        center_pos = QDesktopWidget().availableGeometry().center()
        geometry_frame.moveCenter(center_pos)
        self.move(geometry_frame.topLeft())


    def init_tree(self):
        headers = ['A','B','C','D']

        self.tree_list.setColumnCount(len(headers))
        self.tree_list.setHeaderLabels(headers)

        self.wishlist.setColumnCount(len(headers))
        self.wishlist.setHeaderLabels(headers)


        list_layout = QBoxLayout(QBoxLayout.LeftToRight)
        list_layout.addWidget(self.tree_list)
        list_layout.addWidget(self.wishlist)

        tree_root = QTreeWidget.invisibleRootItem(self.tree_list)
        # add data to QTreeWidget with QTreeWidgetItem
        my_data = ['1','2','3','4']
        item = QTreeWidgetItem()
        for idx, data in enumerate(my_data):
            item.setText(idx, data)

        tree_root.addChild(item)

        my_data = ['11','10','01','D']
        item = QTreeWidgetItem()
        for idx, data in enumerate(my_data):
            item.setText(idx, data)

        tree_root.addChild(item)

        my_data = ['s', 'c', 'c', 'c']
        item = QTreeWidgetItem()
        for idx, data in enumerate(my_data):
            item.setText(idx, data)

        tree_root.addChild(item)

        btn_layout = QBoxLayout(QBoxLayout.RightToLeft)
        btn_layout.addWidget(self.add_button)
        btn_layout.addWidget(self.remove_button)

        main_layout = QBoxLayout(QBoxLayout.TopToBottom)
        main_layout.addLayout(list_layout)
        main_layout.addLayout(btn_layout)

        self.add_button.clicked.connect(self.move_item)
        self.remove_button.clicked.connect(self.move_item)

        self.setLayout(main_layout)
        return main_layout


    def move_item(self):
        sender = self.sender()

        if self.add_button == sender:
            source = self.tree_list
            target = self.wishlist
        else:
            source = self.wishlist
            target = self.tree_list

        item = QTreeWidget.invisibleRootItem(source).takeChild(source.currentIndex().row())
        QTreeWidget.invisibleRootItem(target).addChild(item)

if __name__=='__main__':
    # start the QApplication
    my_application = QApplication(sys.argv)
    # create aplication with the class
    example = my_app_class()
    # use exit for QApplication
    sys.exit(my_application.exec_())

Python 3.8.5 : Testing with openpyxl - part 001 .

The Python executes the code line by line because is an interpreter language.
This allows users to solve issues in the programming area, fast and easy.
I use python versiono 3.8.5 build on Aug 12 2020 at 00:00:00, see the result of interactive mode:

[mythcat@desk ~]$ python
Python 3.8.5 (default, Aug 12 2020, 00:00:00) 
[GCC 10.2.1 20200723 (Red Hat 10.2.1-1)] on linux
Type "help", "copyright", "credits" or "license" for more information.

Today I will show you how to start using openpyxl python package.
Another tutorial about python and documents can be found here.
The openpyxl was created by Eric Gazoni, Charlie Clark, and is a Python library to read/write Excel 2010 xlsx/xlsm/xltx/xltm files.
Let's install the openpyxl python package:

[mythcat@desk ~]$ pip3 install openpyxl --user
Collecting openpyxl
...
Installing collected packages: openpyxl
Successfully installed openpyxl-3.0.5

I tested with the default example source code and works well.

from openpyxl import Workbook
wb = Workbook()

# grab the active worksheet
ws = wb.active

# Data can be assigned directly to cells
ws['A1'] = 42

# Rows can also be appended
ws.append([1, 2, 3])

# Python types will automatically be converted
import datetime
ws['A2'] = datetime.datetime.now()

# Save the file
wb.save("sample.xlsx")

The next example gets all data about asteroids close to planet Earth and put into xlsx file type.
The rows with dangerous asteroids are fill with the red color:

# check asteroids close to planet Earth and add it to file
# import json python package
import json, urllib.request, time

# import openpyxl python package
from openpyxl import Workbook
from openpyxl.styles import PatternFill
# use active worksheet
wb = Workbook()
ws = wb.active

today = time.strftime('%Y-%m-%d', time.gmtime())
print("Time is: " + today)
now = today
# retrieve data about asteroids approaching planet Earth into json format
url = "https://api.nasa.gov/neo/rest/v1/feed?start_date=" + today + "&end_date=" + today + "&api_key=DEMO_KEY"
response = urllib.request.urlopen(url)
result = json.loads(response.read())

print("Now, " + str(result["element_count"]) + " asteroids is close to planet Earth.")
asteroids = result["near_earth_objects"]

no_data = ""
dangerous = ""

ws.append(['today', 'name', 'dangerous?', 'no_data'])
# parsing all the JSON data and add to file
for asteroid in asteroids:
    for field in asteroids[asteroid]:

      try:
        name = "Asteroid Name: " + field["name"]

        if field["is_potentially_hazardous_asteroid"]:   
          dangerous = "... dangerous to planet Earth!"

        else:
          dangerous = "... not threat to planet Earth!"

      except:
        no_data = "no data"
      ws.append([today, name, dangerous, no_data]) 

# create a red patern to fill
redFill = PatternFill(start_color='FFFF0000',
                   end_color='FFFF0000',
                   fill_type='solid')

# check the row with the dangerous asteroid and fill it
for row in ws.rows:
 if row[2].value == "... dangerous to planet Earth!":
  for cell in row:
      cell.fill = redFill

# write all data to file 
wb.save(str(now)+"_asteroids.xlsx")

I run it and result working well:

[mythcat@desk ~]$ python asteroid_data.py 
Time is: 2020-08-23
Now, 9 asteroids is close to planet Earth.

... see the next screenshot: