Building Serverless or Debug APK for React Native apps

Shubhkirti Sharma — Fri, 21 Jun 2019 22:07:08 +0000

So I have been working on React Native for a long time, now and no one actually asked me this till I actually asked myself, “So every time, I have to create a signed APK to test it on another device?”. And as usual, I started googling but came up with a lot of results but none of them actually worked for all the apps that I created or worked with. Eventually, I came up with a solution to build a complete, working serverless APK that runs without the npm packager.

Basically, the process is very easy. Open a terminal/command prompt inside the root directory of your project and run the following commands:

1. Start the node packaging bundler:

npm start

2. When the terminal shows: “Loading dependency graphs….”, open a new terminal in the same directory and now run the following to create a new directory inside the app to store the assets:

mkdir -p android/app/src/main/assets

3. Use react-native’s bundle to bundle the assets in the directory created above:

react-native bundle --platform android --dev false --entry-file index.js --bundle-output android/app/src/main/assets/index.android.bundle --assets-dest android/app/src/main/res

4. Curl the .js files created to the index.android.bundle:

curl "http://localhost:8081/index.bundle?platform=android" -o "android/app/src/main/assets/index.android.bundle"

5. Change to /android directory and run gradlew to build the APK:

cd android && ./gradlew clean assembleDebug

Well, that’s it. Easy, peasy! After everything is done and it shows “Build successful”, your APK will be present in the folder

<project>/android/app/build/outputs/apk/debug

If you have some suggestions, comment below or give a clap!

Fix audio errors in Ubuntu 18.04 with alsamixer

Shubhkirti Sharma — Fri, 21 Jun 2019 21:43:01 +0000

Recently I installed Ubuntu 18.04 on my laptop having an SSD and an internal HDD. Soon after fixing a lot of issues, I encountered through this one and thought maybe a lot of people are going through this. So,why not write about it?

Sometimes it happens that all the audio controls and volume are full and you stilll don't hear any volume coming out of those speakers. I researched a lot and found out that there maybe a problem with the mixer control. And here is what I found out. I ran alsamixer in terminal and checked if all the volumes are full or not.

The 'Headphone' volume was mute even though the 'Master' one was full. And this small thing was the issue. The fix? Simple use arrow keys (left/right) to highlight the headphones tab (it turns red as master is in the above photo). Then use arrow keys(up/down) to increase/decrease the volume. Exit the interface by tapping the Esc key.

You can also use the terminal commands to adjust the volume:

amixer set Headphone 50%

amixer set Master 80%

This finally helped me figure out the issue with the audio. If this does not work, let's just discuss what might be happening!

DEV Community: Shubhkirti Sharma

Building Serverless or Debug APK for React Native apps

Fix audio errors in Ubuntu 18.04 with alsamixer