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GSON LAB to demonstate modifying existing GSON records.

Learning Outcomes:

MainActivity.kt which creates, modifies, displays and then depletes 10 records.

Use LOGCat to visualize this occuring. Just regenerate mainactivity.kt in the previous lab.

Here is a modified version of MainActivity.kt that demonstrates creating, modifying, displaying, and depleting 10 Pokémon records using GSON.

This example will use Logcat to visualize the process.

Here's the updated MainActivity.kt:

package com.example.pokemongsonbattle

import androidx.appcompat.app.AppCompatActivity

import android.os.Bundle

import android.util.Log

import com.google.gson.Gson

import com.google.gson.reflect.TypeToken

class MainActivity : AppCompatActivity() {

private val tag = "PokemonGSONDemo"

private lateinit var pokemonList: MutableList<Pokemon>

private val gson = Gson()

override fun onCreate(savedInstanceState: Bundle?) {

super.onCreate(savedInstanceState)

setContentView(R.layout.activity_main)

createPokemonList()

displayPokemonList("Initial Pokemon List")

modifyPokemonList()

displayPokemonList("Modified Pokemon List")

depletePokemonList()

}

private fun createPokemonList() {

pokemonList = mutableListOf(

Pokemon("Pikachu", 100, 55, 40),

Pokemon("Charmander", 90, 60, 45),

Pokemon("Squirtle", 95, 50, 65),

Pokemon("Bulbasaur", 100, 45, 55),

Pokemon("Jigglypuff", 110, 40, 35),

Pokemon("Meowth", 85, 55, 40),

Pokemon("Psyduck", 90, 50, 50),

Pokemon("Geodude", 100, 70, 80),

Pokemon("Magikarp", 80, 20, 30),

Pokemon("Eevee", 95, 55, 50)

)

Log.d(tag, "Created 10 Pokemon records")

}

private fun displayPokemonList(message: String) {

Log.d(tag, "--- $message ---")

val jsonList = gson.toJson(pokemonList)

Log.d(tag, jsonList)

}

private fun modifyPokemonList() {

pokemonList.forEachIndexed { index, pokemon ->

pokemon.hp += 10

pokemon.attack += 5

Log.d(tag, "Modified Pokemon $index: ${gson.toJson(pokemon)}")

}

private fun depletePokemonList() {

while (pokemonList.isNotEmpty()) {

val removed = pokemonList.removeAt(0)

Log.d(tag, "Removed Pokemon: ${gson.toJson(removed)}")

Log.d(tag, "Remaining Pokemon: ${pokemonList.size}")

}

Log.d(tag, "All Pokemon depleted")

}

data class Pokemon(

val name: String,

var hp: Int,

var attack: Int,

val defense: Int

)

}

This updated MainActivity.kt demonstrates the following:

Creating a list of 10 Pokémon records

Displaying the initial list using GSON

Modifying each Pokémon's HP and attack

Displaying the modified list

Depleting the list one Pokémon at a time

All operations are logged using Logcat for visualization.

To run this lab:

Replace the existing MainActivity.kt in your Android Studio project with this code.

Ensure you have the GSON library in your app's build.gradle file:

implementation 'com.google.code.gson:gson:2.8.9'

Run the app on an emulator or device.

Open the Logcat window in Android Studio.

Filter the Logcat output by entering the tag "PokemonGSONDemo" in the search box.

You'll see the Logcat output showing:

The creation of 10 Pokémon records

The initial JSON representation of the list

Individual modifications to each Pokémon

The modified JSON representation of the list

The removal of each Pokémon until the list is depleted

This lab provides a simple yet effective demonstration of creating, modifying, and manipulating data using GSON, while using Logcat to visualize the process.

GSON Lab Part 3: Updating the GSON Record

Additional lab for GSON, which creates, modifies, displays and then depletes 10 records.

Demonistrate the use LOGCat to visualize this occuring.

This just replaces the mainactivity.kt in the previous lab.

This lab just runs a series of activities you can view in LogCat - This code does not count on Clicking a button to start.

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Modified version of MainActivity.kt that demonstrates creating, modifying, displaying, and depleting 10 Pokémon records using GSON.