Flutter

In the first part of this series, you learned how to create a basic app in Flutter. There you learned only basic structure, some interactivity and you used only Stateless widgets. In this tutorial, you will develop an Expense App to learn state, stateful widget, regular expression, TextField widget, and some concepts in Flutter.

I tried my best to add minimal features so you could easily understand the building blocks for this app.

You will develop the following app with me:

Programming

Web scraping is the process of gathering data automatically by a computer program from different websites. There are many use cases. Many businesses were created solely based on web scarping.

There are different ways to scrape any website using Python. Using the BeautifulSoup library, Scrapy Framework, and Selenium library with a headless web browser.

Using BeautifulSoup or Scrapy Framework, we can easily scrap a normal website where the server generates the HTML files. …

Android Dev

In my last article, I discussed how to reverse engineering an android app. If you did no reverse engineering before just do it to learn how easy it is to reverse an android app to the original source code.

In this article, I will let you know how to protect an Android app from reverse engineering.

If you want to protect your app from reverse engineering free, unfortunately, there is no such tool. What you can do is to make it difficult for the attacker.

There is a detailed article from android developer website where you can know how to…

Flutter

Whether you develop a native app or hybrid app, state management is a common issue to address. To manage a global state in a flutter app, Provider is one of the most popular libraries.

When we develop an iOS app, we have at least one scheme. Many beginner or intermediate developers don’t know that we can add some special commands to create a custom environment to test the app.

Let me tell you how to use different iOS or Mac app schemes in XCode to test an app faster.

I have an iOS app named “Word Search” that I developed long ago in 2013 and still often update the app with new features. In this app, there are some features that are critical to test. For example:

1. Advertise
2. Hints
3. Puzzle to solve

Recently in one of my projects, I found a bug. Basically, I need to loop an array with actions, and based on the action I have to complete a task. So without much thinking, I just used the forEach function to iterate the array. Let me show you a simple example:

As forEach is a closure, I thought if the first if block matched it will return from the iteration. Normally this is how for loop works, you can either use break statement or if the loop inside in a function, you can return to exit from the loop.

…

Sometimes it is critical to know when the local state value changed in a SwiftUI view. In one of my applications, I had a text field, and I had to enable the next button if the user inputs something. I also used the local state variable for the purpose.

For demonstration purposes, I just want to show a green text “Green” below the text field when the user enters something.