A quick cheatsheet of useful snippet for Flutter
A widget is the basic type of controller in Flutter Material.
There are two type of basic Widget we can extend our classes: StatefulWidget or StatelessWidget.
StatefulWidget are all the widget that interally have a dynamic value that can change during usage. It can receive an input value in the constructor or reference to functions. You need to create two classes like:
Here is a high level overview for what you need to do to get most of an Android environment setup and maintained.
Prerequisites (for Homebrew at a minimum, lots of other tools need these too):
xcode-select --install will prompt up a dialog)Install Homebrew:
ruby -e "$(curl -fsSL https://raw.github.com/Homebrew/homebrew/go/install)"
| from random import choice | |
| from scrapy import signals | |
| from scrapy.exceptions import NotConfigured | |
| class RotateUserAgentMiddleware(object): | |
| """Rotate user-agent for each request.""" | |
| def __init__(self, user_agents): | |
| self.enabled = False | |
| self.user_agents = user_agents |
| const scraper = require('./scrape.js') | |
| const models = require('./models.js') | |
| const processModels = models => Promise.all( | |
| models.map(model => processLinks(model, model.urls)) | |
| ).then( | |
| result => console.log(JSON.stringify(result)) | |
| ) | |
| const processLinks = (model, urls) => Promise.all( |
| # import required libraries | |
| import pandas as pd | |
| import yfinance as yf | |
| import numpy as np | |
| import math | |
| # get stock prices | |
| df = yf.download('AAPL', start='2020-01-01', threads= False) | |
| # parameter setup |