Update README.md

README.md

@@ -2,7 +2,63 @@
 
 Android Studios project to open local HTML files in Chrome Custom Tab by hosting local HTTP server using NanoHTTPD.
 
-### Requirements
+### User Requirements
 - Android >= 7.0 (Nougat)
-- Minimum API level : 24
 - Android Chrome browser app
+
+## Prerequisite
+
+### Android Studio
+Android Studio is required for building the APK from the source code
+- Download and Install Android Studio from the official [site](https://developer.android.com/studio)
+
+### Android SDK
+Android SDK (Software Development Kit) contains the required libraries and tools to build the APK
+
+#### Install Android SDK
+1. Open Android Studio (for the first time after installation) and SDK installation will pop up.
+2. Select the installation directory for Andriod SDK.
+3. Click continue and accept to install Andriod SDK.
+
+#### Install required SDK platform
+1. Open Android Studio
+2. In menu bar click, `Tools` -> `SDK Manager`.
+3. A window will pop up with the list of Android versions available.
+4. To install any version, click the checkbox `☐` near the Android Name and click `Apply`. 
+    - Select checkbox `☑` of `Android 7.0 Nougat` and click `Apply`.
+5. Upon successful installation, the `Status` will be changed to `Installed`.
+
+## Building APK
+
+1. Clone [this](https://github.com/sairajzero/AndroidHttpArch) github repo
+```
+git clone https://github.com/sairajzero/AndroidHttpArch.git
+```
+2. Copy any webpage files (html, js, css, svg, images, etc) of your project to the `asset` folder (path: `AndroidHttpArch/app/src/main/assets/`)
+    - AndroidHttpArch
+        - app
+            - src
+                - main
+                    - assets
+```
+cp path-to-your-project/*  AndroidHttpArch/app/src/main/assets
+```
+3. Open `AndroidHttpArch` folder in Android Studio
+    - In Android Studio menubar: Click `File` -> `Open`. Navigate and select `AndroidHttpArch` folder. Click `Ok`.
+4. Edit port and home page in `MainActivity.java`. (path: `AndroidHttpArch/app/src/main/java/com/ranchimall/androidhttparch/MainActivity.java`)
+    - Line 16: Edit port (for local hosting).
+    - Line 17: Edit the starting home page link. (Most projects have `index.html` or `home.html` as starting homepage)
+5. Select Build variant
+    - Click `Build` -> `Select Build Variant`. The `Build Variant` panel will open/pop-up
+    - For `Module`: `app`, select `Active Build Variant` as `release` 
+5. Build the project
+    - Click `Build` -> `Make Project`. (Default windows shortcut: `Ctrl`+`F9`).
+6. Wait for the build process to complete. (A pop up will appear at the bottom upon build completion)
+7. APK file will be generated in the `apk` folder. (path: `AndroidHttpArch/app/build/outputs/apk/`)
+    - AndroidHttpArch
+        - app
+            - build
+                - outputs
+                    - apk
+                    
+The APK file can be distrubuted to users for installing in their Android devices.