Android Crash Course

Introduction

• Presenter: Not specified
• Platform: Brad's Channel
• Prerequisites: Knowledge of Kotlin (link provided in video description)
• Purpose: Build a to-do list app
• Features:
  • Add to-do items
  • Check/uncheck items
  • Delete checked items
  • Note: No database included (data will be lost on app restart)
  • Detailed tutorials available on the presenter's channel

Why Kotlin?

• Trending Alternatives: Flutter, React Native (cross-platform frameworks)
• Recommendation: Start with native Android in Kotlin
  • More features in Kotlin than Java
  • Google is pushing Kotlin for Android development
  • Java is becoming outdated for Android

Installing Android Studio

1. Download:

• Search for "Android Studio download" on Google
  • First link: developer.android.com/studio
  • Accept license agreements

2. Installation:

• Run the downloaded file
  • Install Android Studio and Android Virtual Device
  • Choose standard installation
  • Select dark theme
  • Download required files, SDK tools

Setting Up the Project

• Open Android Studio
• Start a new project
  • Select "Empty Activity"
  • Set application name and package name
  • Ensure language is set to Kotlin
  • Minimum SDK: API 21 (Android Lollipop)
  • Click "Finish"
• Project Structure:
  • MainActivity.kt: The main Kotlin file
  • activity_main.xml: Layout file associated with MainActivity
  • AndroidManifest.xml: Declares app settings and permissions
  • res (Resources) Folder: Contains drawable, layout, and values files
  • build.gradle (Module: app): Define application dependencies, minimum SDK, etc.

Building the Layout

• Edit activity_main.xml:
  • Remove the default "Hello World" TextView
  • Add a RecyclerView for the to-do list
  • Use ConstraintLayout for responsive design
  • Add EditText for input
  • Add buttons for adding and deleting to-do items

Writing Kotlin Code

• Create Model Class:
  • data class ToDo(val title: String, var isChecked: Boolean = false)
• Create Adapter Class:
  • ToDoAdapter: Handles the logic for displaying the to-do list
  • Functions to Override:
    • onCreateViewHolder: Creates the ViewHolder for the RecyclerView
    • getItemCount: Returns the number of items in the list
    • onBindViewHolder: Binds the data to the views
  • ViewHolder Class: Holds the layout of a specific list item
• Define Additional Functions:
  • addToDo: Adds a new to-do item to the list
  • deleteDoneToDos: Deletes all checked to-do items
• Update MainActivity.kt:
  • Set up RecyclerView and Adapter
  • Define onClickListeners for add and delete buttons

Running the App

• Set Up Emulator:
  • Use AVD Manager in Android Studio
  • Create a new virtual device (e.g., Pixel 3a with API 29)
  • Configure and start the virtual device
• Build and Run:
  • Select the virtual device from the dropdown
  • Click the Run button
  • Test adding, checking, and deleting to-do items

Note on Rotations

• Issue: List is cleared on device rotation
• Reason: Activity is recreated on rotation, onCreate function resets the list
• Solution: Advanced topic outside the scope of the crash course

Closing Remarks

• Further Learning: Advanced android topics, databases, networking, media, etc.
• Resources: GitHub link provided for source code
• Thank You: Acknowledgment of Brad's platform and viewers