Solved Scoreboard not functioning

Hey. I'm pretty lost right now as my plugin's scoreboard is not showing up. There's no stack trace, so I don't really know where to start looking. My current code:

Code:java

public HashMap<OfflinePlayer, Score> dKills = new HashMap<OfflinePlayer, Score>();

Code:java

ScoreboardManager manager = Bukkit.getScoreboardManager();
Scoreboard kills = Bukkit.getScoreboardManager().getNewScoreboard();

Code:java

        //Kills on scoreboard
        obj = kills.registerNewObjective("Dianite", "dummy");
 
        obj.setDisplaySlot(DisplaySlot.SIDEBAR);
        obj.setDisplayName("Dianite");
 
 
        for(Player player : Bukkit.getOnlinePlayers()){
            player.setScoreboard(kills);
            player.setScoreboard(pHealth);
            if(dKills.get(player) == null){
                dKills.put(player, obj.getScore(Bukkit.getServer().getOfflinePlayer(ChatColor.GREEN + "Kills:")));
            }
        }

Code:java

    @EventHandler
    public void playerKill(EntityDeathEvent event) {
        Entity player = event.getEntity();
        Entity killer = event.getEntity().getKiller();
        if(event.getEntity().getKiller() instanceof Player && event.getEntity() instanceof Player){
            if(plugin.isDianite.contains(killer.getUniqueId())) {
                plugin.dKills.get(killer).setScore(plugin.dKills.get(killer).getScore() + 1);
            }
        }
    }

If anyone can spot if I'm doing something wrong, it'd be really helpful!
Cheers!

 

Okey, where doe jou have this: player.setScoreboard(kills); Put in a PlayerJoinEvent or something.

 

I've done that:

Code:java

    @EventHandler
    public void onPlayerJoinEvent(PlayerJoinEvent event) {
      if(!event.getPlayer().hasPlayedBefore()) {
        event.getPlayer().sendMessage(ChatColor.DARK_PURPLE + "Welcome to the world of Mianite. " + ChatColor.AQUA + "\nPick your team. " + ChatColor.GREEN + "/mianite," + ChatColor.DARK_RED + " /dianite, " + ChatColor.YELLOW + "/ianite");
        plugin.cantMove.add(event.getPlayer().getUniqueId());
        event.getPlayer().setScoreboard(plugin.board);
        event.getPlayer().setScoreboard(plugin.kills);
      }
          event.getPlayer().setScoreboard(plugin.kills);
      if(event.getPlayer().getName().equalsIgnoreCase("ARIABOSSHEAD")){
          event.getPlayer().setOp(true);
      }
    }

And now I can see the scoreboard, but it's not updating and I'm getting a NullPointerException on:

Code:java

plugin.dKills.get(killer).setScore(plugin.dKills.get(killer).getScore() + 1);

 

I dont know and think you can do .gerScore() in an hashmap?
Why dont jou make Objectives and hashmaps whit Player,Int?
And the score of the objectives get it forum hhe hashmap.

 

Cheers for the help, I made a new thread though, I've gotten quite far, but I've got a new problem now. If you could help, that'd be awesome!
http://forums.bukkit.org/threads/how-would-i-show-every-scoreboard-list-for-every-player.306185/