Loading Game Data via JSON
確認済のバージョン: 5.4
-
難易度: 中級
In this live training session we will learn how to extend our basic Quiz Game created in session one to include: loading game data from an external json file, editor scripting to create a window for editing game data and very basic saving of player progress.


Loading Game Data via JSON
中級 Scripting
Download the starting version of the project here
PlayerProgress
Code snippet
public class PlayerProgress
{
public int highestScore = 0;
}
DataController
Code snippet
using UnityEngine;
using UnityEngine.SceneManagement;
using System.Collections;
using System.IO; // The System.IO namespace contains functions related to loading and saving files
public class DataController : MonoBehaviour
{
private RoundData[] allRoundData;
private PlayerProgress playerProgress;
private string gameDataFileName = "data.json";
void Start()
{
DontDestroyOnLoad(gameObject);
LoadGameData();
LoadPlayerProgress();
SceneManager.LoadScene("MenuScreen");
}
public RoundData GetCurrentRoundData()
{
// If we wanted to return different rounds, we could do that here
// We could store an int representing the current round index in PlayerProgress
return allRoundData[0];
}
public void SubmitNewPlayerScore(int newScore)
{
// If newScore is greater than playerProgress.highestScore, update playerProgress with the new value and call SavePlayerProgress()
if(newScore > playerProgress.highestScore)
{
playerProgress.highestScore = newScore;
SavePlayerProgress();
}
}
public int GetHighestPlayerScore()
{
return playerProgress.highestScore;
}
private void LoadGameData()
{
// Path.Combine combines strings into a file path
// Application.StreamingAssets points to Assets/StreamingAssets in the Editor, and the StreamingAssets folder in a build
string filePath = Path.Combine(Application.streamingAssetsPath, gameDataFileName);
if(File.Exists(filePath))
{
// Read the json from the file into a string
string dataAsJson = File.ReadAllText(filePath);
// Pass the json to JsonUtility, and tell it to create a GameData object from it
GameData loadedData = JsonUtility.FromJson<GameData>(dataAsJson);
// Retrieve the allRoundData property of loadedData
allRoundData = loadedData.allRoundData;
}
else
{
Debug.LogError("Cannot load game data!");
}
}
// This function could be extended easily to handle any additional data we wanted to store in our PlayerProgress object
private void LoadPlayerProgress()
{
// Create a new PlayerProgress object
playerProgress = new PlayerProgress();
// If PlayerPrefs contains a key called "highestScore", set the value of playerProgress.highestScore using the value associated with that key
if(PlayerPrefs.HasKey("highestScore"))
{
playerProgress.highestScore = PlayerPrefs.GetInt("highestScore");
}
}
// This function could be extended easily to handle any additional data we wanted to store in our PlayerProgress object
private void SavePlayerProgress()
{
// Save the value playerProgress.highestScore to PlayerPrefs, with a key of "highestScore"
PlayerPrefs.SetInt("highestScore", playerProgress.highestScore);
}
}
GameController
Code snippet
using UnityEngine;
using UnityEngine.UI;
using UnityEngine.SceneManagement;
using System.Collections.Generic;
public class GameController : MonoBehaviour
{
public SimpleObjectPool answerButtonObjectPool;
public Text questionText;
public Text scoreDisplay;
public Text timeRemainingDisplay;
public Transform answerButtonParent;
public GameObject questionDisplay;
public GameObject roundEndDisplay;
public Text highScoreDisplay;
private DataController dataController;
private RoundData currentRoundData;
private QuestionData[] questionPool;
private bool isRoundActive = false;
private float timeRemaining;
private int playerScore;
private int questionIndex;
private List<GameObject> answerButtonGameObjects = new List<GameObject>();
void Start()
{
dataController = FindObjectOfType<DataController>(); // Store a reference to the DataController so we can request the data we need for this round
currentRoundData = dataController.GetCurrentRoundData(); // Ask the DataController for the data for the current round. At the moment, we only have one round - but we could extend this
questionPool = currentRoundData.questions; // Take a copy of the questions so we could shuffle the pool or drop questions from it without affecting the original RoundData object
timeRemaining = currentRoundData.timeLimitInSeconds; // Set the time limit for this round based on the RoundData object
UpdateTimeRemainingDisplay();
playerScore = 0;
questionIndex = 0;
ShowQuestion();
isRoundActive = true;
}
void Update()
{
if (isRoundActive)
{
timeRemaining -= Time.deltaTime; // If the round is active, subtract the time since Update() was last called from timeRemaining
UpdateTimeRemainingDisplay();
if (timeRemaining <= 0f) // If timeRemaining is 0 or less, the round ends
{
EndRound();
}
}
}
void ShowQuestion()
{
RemoveAnswerButtons();
QuestionData questionData = questionPool[questionIndex]; // Get the QuestionData for the current question
questionText.text = questionData.questionText; // Update questionText with the correct text
for (int i = 0; i < questionData.answers.Length; i ++) // For every AnswerData in the current QuestionData...
{
GameObject answerButtonGameObject = answerButtonObjectPool.GetObject(); // Spawn an AnswerButton from the object pool
answerButtonGameObjects.Add(answerButtonGameObject);
answerButtonGameObject.transform.SetParent(answerButtonParent);
answerButtonGameObject.transform.localScale = Vector3.one;
AnswerButton answerButton = answerButtonGameObject.GetComponent<AnswerButton>();
answerButton.SetUp(questionData.answers[i]); // Pass the AnswerData to the AnswerButton so the AnswerButton knows what text to display and whether it is the correct answer
}
}
void RemoveAnswerButtons()
{
while (answerButtonGameObjects.Count > 0) // Return all spawned AnswerButtons to the object pool
{
answerButtonObjectPool.ReturnObject(answerButtonGameObjects[0]);
answerButtonGameObjects.RemoveAt(0);
}
}
public void AnswerButtonClicked(bool isCorrect)
{
if (isCorrect)
{
playerScore += currentRoundData.pointsAddedForCorrectAnswer; // If the AnswerButton that was clicked was the correct answer, add points
scoreDisplay.text = playerScore.ToString();
}
if(questionPool.Length > questionIndex + 1) // If there are more questions, show the next question
{
questionIndex++;
ShowQuestion();
}
else // If there are no more questions, the round ends
{
EndRound();
}
}
private void UpdateTimeRemainingDisplay()
{
timeRemainingDisplay.text = Mathf.Round(timeRemaining).ToString();
}
public void EndRound()
{
isRoundActive = false;
dataController.SubmitNewPlayerScore(playerScore);
highScoreDisplay.text = dataController.GetHighestPlayerScore().ToString();
questionDisplay.SetActive(false);
roundEndDisplay.SetActive(true);
}
public void ReturnToMenu()
{
SceneManager.LoadScene("MenuScreen");
}
}
GameDataEditor
Code snippet
using UnityEngine;
using UnityEditor;
using System.Collections;
using System.IO;
public class GameDataEditor : EditorWindow
{
public GameData gameData;
private string gameDataProjectFilePath = "/StreamingAssets/data.json";
[MenuItem ("Window/Game Data Editor")]
static void Init()
{
EditorWindow.GetWindow (typeof(GameDataEditor)).Show ();
}
void OnGUI()
{
if (gameData != null)
{
SerializedObject serializedObject = new SerializedObject (this);
SerializedProperty serializedProperty = serializedObject.FindProperty ("gameData");
EditorGUILayout.PropertyField (serializedProperty, true);
serializedObject.ApplyModifiedProperties ();
if (GUILayout.Button ("Save data"))
{
SaveGameData();
}
}
if (GUILayout.Button ("Load data"))
{
LoadGameData();
}
}
private void LoadGameData()
{
string filePath = Application.dataPath + gameDataProjectFilePath;
if (File.Exists (filePath)) {
string dataAsJson = File.ReadAllText (filePath);
gameData = JsonUtility.FromJson<GameData> (dataAsJson);
} else
{
gameData = new GameData();
}
}
private void SaveGameData()
{
string dataAsJson = JsonUtility.ToJson (gameData);
string filePath = Application.dataPath + gameDataProjectFilePath;
File.WriteAllText (filePath, dataAsJson);
}
}