Solana Block Explorer — GetBlock JSON-RPC

An Android application that uses the GetBlock JSON-RPC API to explore the Solana blockchain in real time. Built with Kotlin, Jetpack Compose, and the MVI architecture pattern.

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Screenshots

Main Screen	Block Details

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Features

• 📊 SOL Supply — displays circulating, non-circulating, and total SOL supply with percentages
• 🕐 Epoch Info — current epoch number, slot range, progress percentage, and estimated time remaining
• 📋 Block List — fetches the 10 most recent confirmed blocks with timestamp, blockhash, and validator reward
• 🔍 Block Search — search any block by slot number and navigate to its detail page
• 🔄 Auto-refresh — data is automatically refreshed every 60 seconds
• 📱 Block Detail Screen — full block information including blockhash, previous blockhash, elapsed time, and total reward in SOL

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Tech Stack

Category	Technology
Language	Kotlin 2.0
UI	Jetpack Compose + Material 3
Architecture	MVI (Model–View–Intent)
Navigation	Navigation Compose
Networking	Ktor Client (CIO engine)
Serialization	kotlinx.serialization
Async	Kotlin Coroutines + StateFlow / SharedFlow
Min SDK	24 (Android 7.0)
Target SDK	35 (Android 15)

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Architecture

The project follows a clean MVI pattern:

app/
└── src/main/java/com/example/getblock/
    ├── data/
    │   ├── api/          # ApiService (Ktor), ApiKey / BASE_URL
    │   └── model/        # RpcRequest, RpcResponse, Block, Epoch, Supply
    ├── domain/
    │   ├── UseCase.kt    # Business logic: fetch supply, epoch, block list
    │   └── Utils.kt      # Helpers: time formatting, percentage calculation
    └── mvi/
        ├── intent/       # MainIntent, BlockIntent (sealed classes)
        ├── reducer/      # Pure reducer functions
        ├── state/        # MainState, BlockState
        ├── viewmodel/    # MainViewModel, BlockViewModel
        └── view/
            ├── MainScreen.kt
            ├── BlockScreen.kt
            └── components/   # SupplyCard, EpochCard, BlockListCard, BlockCard, SearchBar, TopPart

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How It Works

1. On launch, MainViewModel immediately triggers LoadData and enters a 60-second polling loop.
2. UseCase.fetchData() fires three parallel RPC calls via ApiService:
   • getSupply → circulating / non-circulating / total SOL
   • getEpochInfo → current epoch, slot index, slots in epoch
   • getBlocks + per-block getBlock → list of the 10 latest blocks with details
3. All state is held in MainState (a single immutable data class) and updated through the mainReducer.
4. Tapping a block row or submitting a slot ID in the search bar navigates to BlockDetailScreen via NavHostController.

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Getting Started

Prerequisites

• Android Studio Hedgehog or newer
• A free GetBlock account and API key

Setup

1. Clone the repository:

   git clone https://github.com/your-username/solana-block-explorer.git

2. Open the project in Android Studio.

3. Replace the API key in ApiKey.kt:

   private const val API_KEY = "YOUR_GETBLOCK_API_KEY"

4. Build and run on an emulator or physical device (API 24+).

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RPC Methods Used

Method	Purpose
getSupply	Total, circulating, and non-circulating SOL
getEpochInfo	Current epoch number, slot index, slots in epoch
getBlocks	List of confirmed slot numbers in a range
getBlock	Full block data (blockhash, blockTime, rewards)

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License

This project is open source and available under the MIT License.