Android-Hello World!

You need – Android Studio (on PC), a Mobile Device & a Data cable (PC-Mobile). Forget working on Emulator.

Android Programmer faces many compatibility issues in the beginning.
  • H/W – Hardware graphics card is old and not supporting. You might end up replacing your motherboard which is bit expensive and time consuming.
  • O/S – Some Operating Systems do not have support for Hardware Acceleration Execution Manager (HAXM). Enabling Intel VT (Virtual Technology) in BIOS (Basic Input Output System) for Graphics Processing Unit (GPU) may be futile.
  • S/W – Choosing Android Studio Version, Emulator version, Android Version in Emulator is a matter of trial and error exercise.
  • Drivers – If you are choosing to bypass emulator, thereby working directly on device, then some mobile device drivers are not easily available. Even if you manage to download, those may not be supported by your existing O/S.

Avoid Windows-7 as the Microsoft / Intel Support is stopped for it. Avoid Windows-10 as many developers complain it being memory hungry thus. Avoid Emulator as it is extremely memory hungry.

You might need to install HAXM (Hardware Accelerated Execution Manager) which also needs Intel VT “Enabled” in BIOS Security Setup. However, Windows 7 fails even then to support starting ADM (Android Device Manager) as well as ADM Server for Virtual Device (Emulator) in Android Studio. Dodging Emulator and going directly with Device also might not help as it starts giving driver issues.

I chose Linux over Windows, Mobile device over Emulator I used following platform and configuration.

LINUX
NAME="Ubuntu"
VERSION="20.04.2 LTS (Focal Fossa)"

ANDROID STUDIO
Arctic Fox | 2020.3.1
Minimum SDK API-21 Android (Lollipop) 5.0 [Approximately runs on 94.1% of devices]

THIS ALSO WORKS => Minimum SDK API-18 Android 4.3 (Jelly Bean) [Approximately runs on 98.4% of devices]
But the trade-off is "ACCEPTABILITY OF MAXIMUM DEVICES v/s NEW API WITH NEW FEATURES". And newer the API, more the longevity of its support and acceptance in future. So, the choice is yours. "I chose Lollipop over Jelly Bean".

MOBILE VIVO
Vivo 1906
Android Version 11
Funtouch OS
And it works just fine! Let’s see programs that work.

PREPARE YOUR MOBILE

Go to settings of your mobile.

SETTINGS

Go to Systems Management.

SYSTEMS MANAGEMENT

Go to About Phone

ABOUT

Tap 7 times on Software Versions to activate Developer Option.

sw version

If you try to re-tap, it says you are already a Developer. So no need to tap again.

Already Developer

See of you get a Developer Option (which is normally not visible before 7 times tapping).

Turn Developer Option, Stay Awake & Debug Enable ON.

Enable Stay Awake

Enable Debug mode ON

Debug Enabled

START ANDROID STUDIO

FILE >> NEW PROJECT

Activity = Empty Activity. (For Phone / Tablet)

(Choose Language = Java, SDK as shown above)

New Project Settings

The immediate temporary screen that appears is as below. (Be patient).

Then appears your “MAIN ACTIVITY” screen.

Main Activity Screen

CONNECT YOUR MOBILE TO PC USING DATA CABLE.

RUN >> SELECT DEVICE

My mobile is VIVO so I will choose Vivo.

Choose Mobile

Run the application.

The Gradle Builds your application (Takes a while for first time, be patient) . After building, it copies the application on your mobile devices that is connected.


Mobile Screen

Depending on activity you chose, you will get interface. If you chose empty activity (as instructed above) then you will get empty screen.

CONGRATULATIONS! Your first Android Mobile Sample Hello world App on your mobile device.