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📱IMStudio 🎓is a team that doesn’t stop moving. We expound on subjects as varied as developing a software application and through to disruptive technologies.🎓

1. Identify the problems

👉 Step 1: I am using React Native version 0.63.2 like below, and I want to build an android app by using Fastlane for CI/CD integration.

As an Android developer, we have all worked with traditional layouts: LinearLayout and RelativeLayout. For me, I think it is quite an approach with everyone, but it will bring a lot of bad problems about performance in our application. Furthermore, with many complex layouts nowadays, using the old layouts to handle them is so difficult. Therefore, Google introduced the library in the 2016 Google I.O conference talk about ConstraintLayout — It helps to avoid problems that the old brings.

I am delighted to be here today to help you understand all of the things the new layout — ConstraintLayout. Even…


Java HashMap class is an implementation of Map interface based on hash table. It stores elements in key & value pairs which is denoted as HashMap<Key, Value> or HashMap<K, V>.

It extends AbstractMap class, and implements Map interface and can be accessed by importing java.util package. Declaration of this class is given below.

There are only two hard things in Computer Science: cache invalidation and naming things PHIL KARLTON

In computer programming, a naming convention is a set of rules for choosing the character sequence to be used for identifiers that denote variables, types, functions, and other entities in source code and documentation.

Reasons for using a naming convention (as opposed to allowing programmers to choose any character sequence) include the following:

  • To reduce the effort needed to read and understand source code;[1]
  • To enable code reviews to focus on more important issues than arguing over syntax and naming standards.
  • To enable code…

The NDK supports multiple C++ runtime libraries. This document provides information about these libraries, the tradeoffs involved, and how to use them.

C++ runtime libraries

Table 1. NDK C++ Runtimes and Features.

NameFeatureslibc++Modern C++ support.systemnew and delete. (Deprecated in r18.)noneNo headers, limited C++.

libc++ is available as both a static and shared library.


LLVM’s libc++ is the C++ standard library that has been used by the Android OS since Lollipop, and as of NDK r18 is the only STL available in the NDK.

Note: See the C++14 Status, C++17 Status, and C++2a Status pages for full details of the expected level of C++…

1. What is VLC?

VLC is a free and open-source cross-platform multimedia player and framework that plays most multimedia files as well as DVDs, Audio CDs, VCDs, and various streaming protocols.

2. What is VLC for Android

VLC for Android is a full port of VLC media player to the Android™ platform. It can play any video and audio files, network streams, and DVD ISOs, like the classic version of VLC. VLC features a full music player, a media database, equalizer and filters, and numerous other features.

LibVLC is the Android library embedding VLC engine, which provides a lot of multimedia features, like:

  • Play every media file formats, every…

1. android:minSdkVersion

The min sdk version is the minimum version of the Android operating system required to run your application.

An integer designating the minimum API Level required for the application to run. The Android system will prevent the user from installing the application if the system’s API Level is lower than the value specified in this attribute. You should always declare this attribute.

Caution: If you do not declare this attribute, the system assumes a default value of “1”, which indicates that your application is compatible with all versions of Android. If your application is not compatible with all versions (for…


Both libraries have almost same syntax if you want to simply load the image from the URL and display them into the image view. Both support the fade animations and center crop. You can also add placeholder image to display while loading the image or while the image loading fails.





Disk caching:

Both the library supports caching the image in the disk. They download the images from the URL and store those images on the disk by caching. But there are some differences how they store the images in the cache.

  • Picasso downloads the image and stores the full-size image…

1) Why String, Integer and other wrapper classes are considered good keys?

The very basic need for designing a good key is that “we should be able to retrieve the value object back from the map without failure”, right?Otherwise no matter how fancy data structure you build, it will be of no use. To decide that we have created a good key. Key’s hash code is used primarily in conjunction to its equals() method, for putting a key in map and then searching it back from map. …


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