error CS0120: An object reference is required to access non-static member

I was making a chat for my game, after I finished scripting it in C# I got this error:

 Assets/chat/chat.cs(158,45): error CS0120: An object reference is required to access non-static member `UnityEngine.NetworkView.RPC(string, UnityEngine.RPCMode, params object[])'

I had also some other errors which I fixed but however I can't fix this one and truly need your help. I would appreciate any kind of help. Here's My Code:

 using UnityEngine;
 using System.Collections;
 
 public class chat : MonoBehaviour {
     
     bool usingChat = false;
     bool showChat = false;
     
     string inputField ="";
     
     Vector2 scrollposition;
     int width = 500;
     int height = 100;
     string playerName;
     float lastUnfocusTime = 0;
     Rect window;
     
     ArrayList playerList = new ArrayList();
     
     class PlayerNode
     {
         public string playerName;
         public NetworkPlayer player;
     }
     
     ArrayList chatEntires = new ArrayList();
     class chatEntry
     {
     public string name ="";
         public string text ="";
     }
     
     
     void Start () 
     {
     window = new Rect(Screen.width /2 - width /2, Screen.height - height + 5, width, height);
     playerName = PlayerPrefs.GetString("playerName", "");
         
         if (playerName=="") playerName = "RandomName" + Random.Range(1,999);
     }
     
     void OnConnectToServer ()
     {
     ShowChatWindow();
         networkView.RPC("TellServerOurName", RPCMode.Server, playerName);
         addGameChatMessage(playerName + " has just joined the chat!");
     }
     
     void OnServerIntialized()
     {
         PlayerNode newEntry = new PlayerNode();
         newEntry.playerName = playerName;
         newEntry.player = Network.player;
         playerList.Add(newEntry);
         addGameChatMessage(playerName + "has just joined the chat!");
     }
     
     PlayerNode GetPlayerNode(NetworkPlayer netPlay)
     {
         foreach (PlayerNode entry in playerList)
         {
         if(entry.player == netPlay)
                 return entry;
         }
         Debug.LogError("GetPlayerNode: Requested a playernode of non-existing player!");
         return null;
     }
     
     void OnPlayerDisconnected(NetworkPlayer netPlayer)
     {
         addGameChatMessage("A Player has disconnected");
         playerList.Remove(GetPlayerNode(netPlayer));
     }
         void OnDisconnectedFromServer()
     {
        CloseChatWindow();
     }
     
     [RPC]
     void TellServerOurName(string name, NetworkMessageInfo info)
     {
         PlayerNode newEntry = new PlayerNode();
         newEntry.playerName = playerName;
         newEntry.player = Network.player;
         playerList.Add(newEntry);
         addGameChatMessage(playerName + " has just joined the chat!");
     }
     void CloseChatWindow()
     {
         showChat = false;
         inputField = "";
         chatEntires = new ArrayList();
     }
     void ShowChatWindow()
     {
         showChat = false;
         inputField = "";
         chatEntires = new ArrayList();
     }
     
     void OnGUI()
     {
         
         if(!showChat) return;
         if (Event.current.type == EventType.keyDown && Event.current.character == '\n' & inputField.Length <= 0 )
         {
             if(lastUnfocusTime + .25f < Time.time)
             {
                 usingChat = true;
                 GUI.FocusWindow(5);
                 GUI.FocusControl("Chat input field");
             }
         }
         
         window = GUI.Window(5, window, GlobalChatWindow, "");
     }
     void GlobalChatWindow(int id)
     {
         GUILayout.BeginVertical();
         GUILayout.Space(10);
         GUILayout.EndVertical();
         
         scrollposition = GUILayout.BeginScrollView(scrollposition);
         foreach (chatEntry entry in chatEntires)
         {
             GUILayout.BeginHorizontal();
             if(entry.name == " - ")
                 GUILayout.Label(entry.name + entry.text);
             else
                 GUILayout.Label(entry.name + ": " + entry.text);
             
             GUILayout.EndHorizontal();
             GUILayout.Space(2);
         }
         
         GUILayout.EndScrollView();
         if(Event.current.type == EventType.keyDown && Event.current.character == '\n' & inputField.Length <= 0)
         {
             HitEnter(inputField);
             GUI.SetNextControlName("Chat input field");
             inputField = GUILayout.TextField(inputField);
             
             if (Input.GetKeyDown("mouse 0"))
             {
                 if (usingChat)
                 {
                     usingChat = false;
                     GUI.UnfocusWindow();
                     lastUnfocusTime = Time.time;
                 }
             }
 
         }
     }
     void HitEnter(string msg)
             {
                 msg = msg.Replace('\n', ' ') ;
                 NetworkView.RPC("ApplyGlobalChatText", RPCMode.All, playerName, msg);
             }
 [RPC]
     void ApplyGlobalChatText(string name, string msg)
     {
         chatEntry entry = new chatEntry();
         entry.name = name;
         entry.text = msg;
         
         chatEntires.Add(entry);
         
         if (chatEntires.Count > 4)
             chatEntires.RemoveAt(0);
         
         scrollposition.y = 1000000;
         inputField = "";
         
     }
     
     void addGameChatMessage(string str)
     {
         ApplyGlobalChatText(" - ", str);
         if(Network.connections.Length > 0)
             networkView.RPC("ApplyGlobalChatText", RPCMode.Others , " - ", str);
     }
 }