InstantiateDialog.cs

using UnityEngine;
using System.Collections;
using System.Collections.Generic;

public class InstantiateDialog : MonoBehaviour
{
    public TextAsset ta;
    public Dialog dialog;
    public int currentNode;
    public bool ShowDialogue;

    public GUISkin skin;

    public List<Answer> answers = new List<Answer>();

    void Start ()
    {
        dialog = Dialog.Load (ta);
        skin = Resources.Load ("Skin") as GUISkin;
    }

    void Update()
    {
        UpdateAnswers ();
    }

    void UpdateAnswers ()
    {
        answers.Clear ();
        for (int i = 0; i < dialog.nodes [currentNode].answers.Length; i++)
        {
            if(dialog.nodes [currentNode].answers [i].QuestName==null||dialog.nodes [currentNode].answers [i].NeedQuestValue==PlayerPrefs.GetInt(dialog.nodes [currentNode].answers [i].QuestName))
            answers.Add (dialog.nodes [currentNode].answers [i]);
        }
    }

    void OnGUI()
    {
        GUI.skin = skin;
        if (ShowDialogue) {
            GUI.Box (new Rect (Screen.width / 2 - 300, Screen.height - 300, 600, 250), "");
            GUI.Label (new Rect (Screen.width / 2 - 250, Screen.height - 280, 500, 90), dialog.nodes [currentNode].NpcText);
            for (int i = 0; i < answers.Count; i++)
            {
                if (GUI.Button (new Rect (Screen.width / 2 - 250, Screen.height - 200 + 25 * i, 500, 25), answers [i].text, skin.label))
                {
                    if(answers[i].QuestValue>0)
                    {
                        PlayerPrefs.SetInt (answers [i].QuestName, answers[i].QuestValue);
                    }
                    if (answers [i].end == "true")
                    {
                        ShowDialogue = false;
                    }
                    if (answers [i].RewardGold > 0)
                    {
                        Character.Gold += answers [i].RewardGold;
                    }
                    currentNode = answers [i].nextNode;
                }
            }
        }
    }
}