Android Home Task

1. Create a new private repo and invite: @mario-deblock.
2. Start or upload your project.
3. We take into account:

• UI only using Compose
• Single Activity with Compose - Navigation (no fragments) MVVM
• Dependency injection with Dagger or Hilt
• Repository pattern
• 100% Kotlin
• Coroutines
• Flow

Some easy steps to kick start your project:

1. Android Studio -> New project → Empty Activity (Compose)
2. Configuration file language: Kotlin DSL
3. Unit test with MOCKK
4. UI test with Espresso
5. Networking with Retrofit
6. Jetpack libs

Requirements

Design

[Figma file to follow colors, spacing, icons, etc here](https://www.figma.com/file/SaT9UfRVHwrcpCN8p1kVKl/Test-project?type=design&node-id=0%3A1&mode=design&t=gS6wgz3FuWBBJfqV-1

Features

A Deblock user has a crypto wallet. This crypto wallet contains ETH. Assume the current user has a wallet balance of 10 ETH.

In this screen:

• As a user I can send ETH and select the amount without exceeding the wallet balance.
• As a user I can select a currency to display the equivalent amount in EUR, USD or GBP from a modal with these fixed options.
• As a user I can also switch the primary label of the component to be ETH or the selected currency (this will change the label displayed on the Send button too). As I type in this label an amount, it should convert the equivalent ETH<>FIAT
• As a user I can see the estimated network fees in ETH.

You will need to consume 2 data points:

1. Exchange rate (ETH to eur/gbp/usd)
2. Estimated network fees

1. Obtaining Exchange rate

For the exchange rate, you can consume any free API, but here you have a working example you can use:

Request

https://api.coingecko.com/api/v3/simple/price?ids=ethereum&vs_currencies=usd

Response

{
  "ethereum": {
    "usd": 1644.1
  }
}

vs_currencies accepts usd, eur and gbp so you will be covered for this task :)

2. Estimated Network Fees

For the ETH Network fees, you can use the following formula + API to obtain the data

Formula

Est Network fees = 21000 * {gasPrice} / 100000000

To obtain the current {gasPrice}:

Request

https://api.etherscan.io/api?module=gastracker&action=gasoracle&apikey=YourApiKeyToken

If you dont have an apiToken you have a rate limit of 1/5 seconds.

Response

{"status":"1","message":"OK-Missing/Invalid API Key, rate limit of 1/5sec applied","result":{"LastBlock":"18041185","SafeGasPrice":"13","ProposeGasPrice":"14","FastGasPrice":"14","suggestBaseFee":"12.086368893","gasUsedRatio":"0.505199894363513,0.45067015395881,0.364857033333333,0.700552333333333,0.461159333333333"}}

Extract and use the FastGasPrice param.

So the estimated gas fee to be displayed is equal to

21000 * {FastGasPrice} / 100000000

What we look for

• Be pixel perfect
• Animate the modal
• Clean code (networking, UI, simplicity)
• BE FAST EXECUTING.