Solved GUI Next Page Error

Hello i have this
But it throws an error when i go to page number 2

at java.lang.Thread.run(Unknown Source) [?:1.8.0_121]
Caused by: java.lang.IndexOutOfBoundsException: Index: 53, Size: 45
at java.util.ArrayList.rangeCheck(Unknown Source) ~[?:1.8.0_121]

But if i remove this i can go to page 2

Code:

for (ItemStack is : items.subList(si, ei)) {
                  inventory.addItem(is);
              }

Sorry I'm not so good at English

Code:

public void createGUI(Player p) {
        if (Config.getInstance().getData().contains("Reports")) {
            ArrayList<ItemStack> items = new ArrayList<ItemStack>();
        for (String z : Config.getInstance().getData().getConfigurationSection("Reports").getKeys(false)) {
              ItemStack item = new ItemStack(Material.PAPER, 1);
              ItemMeta meta = item.getItemMeta();
              meta.setDisplayName(Config.getInstance().getData().getString("Reports" + "." + z + "." + "Reporter") + "´s report" + " ID: " + z);
              List<String> lore = new ArrayList<String>();
              lore.add("Reporter: " + Config.getInstance().getData().getString("Reports" + "." + z + "." + "Reporter"));
              lore.add("Reported: " + Config.getInstance().getData().getString("Reports" + "." + z + "." + "Reported"));
              lore.add("Reason: " + Config.getInstance().getData().getString("Reports" + "." + z + "." + "Reason"));
              lore.add("Status: " + Config.getInstance().getData().getString("Reports" + "." + z + "." + "Status"));
              meta.setLore(lore);
              item.setItemMeta(meta);
            
              items.add(item);
            
              boolean next = true;
            
              int epp = 52;
              int si = (page - 1) * epp;
              int ei = si + epp;
              if (ei > items.size()) {
                  ei = items.size();
                  next = false;
              }
              p.sendMessage("Per Page: " + epp);
              p.sendMessage("Page: " + page);
              p.sendMessage("Start Index: " + si);
              p.sendMessage("End Index: " + ei);
              Inventory inventory = Bukkit.createInventory(null, 54, "Reports " + "Page: " + page);
              if (next) {
                      ItemStack nextpage = new ItemStack(Material.ARROW, 1);
                        ItemMeta nextpagemeta = nextpage.getItemMeta();
                        nextpagemeta.setDisplayName("Next Page");
                      nextpage.setItemMeta(nextpagemeta);
                        inventory.setItem(53, nextpage);
              }
              if (page != 1) {
                      inventory.setItem(52, new ItemStack(Material.STICK));
              }
            
              for (ItemStack is : items.subList(si, ei)) {
                  inventory.addItem(is);
              }
            
              p.openInventory(inventory);
        }
        }
    }

 

ei is greater than the lists' side. Ei is equal to 53, when it should be 45.

 

Yes but if i remove this i works

Code:

for (ItemStack is : items.subList(si, ei)) {
                  inventory.addItem(is);
              }

and when i add this

Code:

for (ItemStack is : items.subList(si, ei)) {
                  inventory.addItem(is);
              }

the end index is == 1

 

@mathkot59
Its not working because you are getting a sublist, where the end index is trying to be 53. Make sure the largest index is less than the list's size.

 

@Zombie_Striker
I dont understand what im doing wrong?
and I'm also not so good at GUI

 

He's using a totally different method. The only thing I can do is give him mine code but since I'm using custom classes it's hard for him to understand .

UPDATE:

Okay so first you need a hashMap that stores a page number their on for each player.
so : <Player, Integer>
collect all items in a list of ItemStack 's .

Now get the page number and store it in a variable

Now create a new Int variable called index.
int amtPages = 12; // ammount of items you want for each page
int index = thePage * amtPages - amtPages;

now create another variable: endIndex

int endIndex = Math.min(index+amtPages,itemList.size());

and now the for loop:

for (; index < endIndex; index++)
{
ItemStack is = itemList.get(index);
inv.setItem(index%amtMax);

}

// open inventory ... done


To change pages just change the page number in the HashMap and open the inventory again.

 

How can i solve this?
i have tried this

Code:

if (items.iterator().hasNext()) {
                  inventory.addItem(item);
              }

but i returns the same on page 1 and 2 and only shows 1 per page
Sorry I'm not so good at English

 

don't use addItem. That will Add another item and you won't have control over the slots.

 

How do i add the items to the inventory
i have this
inventory.setItem(index, what do i put here?);

 

There goes Your itemstack from the list

 

Okay but i have an error when i go to page 2

Code:

[23:06:03 ERROR]: Could not pass event InventoryClickEvent to Report v1.0
org.bukkit.event.EventException
        at org.bukkit.plugin.java.JavaPluginLoader$1.execute(JavaPluginLoader.java:310) ~[spigot-1.11.2.jar:git-Spigot-db6de12-18fbb24]
        at org.bukkit.plugin.RegisteredListener.callEvent(RegisteredListener.java:62) ~[spigot-1.11.2.jar:git-Spigot-db6de12-18fbb24]
        at org.bukkit.plugin.SimplePluginManager.fireEvent(SimplePluginManager.java:502) [spigot-1.11.2.jar:git-Spigot-db6de12-18fbb24]
        at org.bukkit.plugin.SimplePluginManager.callEvent(SimplePluginManager.java:487) [spigot-1.11.2.jar:git-Spigot-db6de12-18fbb24]
        at net.minecraft.server.v1_8_R3.PlayerConnection.a(PlayerConnection.java:1630) [spigot-1.11.2.jar:git-Spigot-db6de12-18fbb24]
        at net.minecraft.server.v1_8_R3.PacketPlayInWindowClick.a(SourceFile:31) [spigot-1.11.2.jar:git-Spigot-db6de12-18fbb24]
        at net.minecraft.server.v1_8_R3.PacketPlayInWindowClick.a(SourceFile:9) [spigot-1.11.2.jar:git-Spigot-db6de12-18fbb24]
        at net.minecraft.server.v1_8_R3.PlayerConnectionUtils$1.run(SourceFile:13) [spigot-1.11.2.jar:git-Spigot-db6de12-18fbb24]
        at java.util.concurrent.Executors$RunnableAdapter.call(Unknown Source) [?:1.8.0_121]
        at java.util.concurrent.FutureTask.run(Unknown Source) [?:1.8.0_121]
        at net.minecraft.server.v1_8_R3.SystemUtils.a(SourceFile:44) [spigot-1.11.2.jar:git-Spigot-db6de12-18fbb24]
        at net.minecraft.server.v1_8_R3.MinecraftServer.B(MinecraftServer.java:715) [spigot-1.11.2.jar:git-Spigot-db6de12-18fbb24]
        at net.minecraft.server.v1_8_R3.DedicatedServer.B(DedicatedServer.java:374) [spigot-1.11.2.jar:git-Spigot-db6de12-18fbb24]
        at net.minecraft.server.v1_8_R3.MinecraftServer.A(MinecraftServer.java:654) [spigot-1.11.2.jar:git-Spigot-db6de12-18fbb24]
        at net.minecraft.server.v1_8_R3.MinecraftServer.run(MinecraftServer.java:557) [spigot-1.11.2.jar:git-Spigot-db6de12-18fbb24]
        at java.lang.Thread.run(Unknown Source) [?:1.8.0_121]
Caused by: java.lang.ArrayIndexOutOfBoundsException: 54
        at org.bukkit.craftbukkit.v1_8_R3.inventory.CraftInventoryCustom$MinecraftInventory.setItem(CraftInventoryCustom.java:105) ~[spigot-1.11.2.jar:git-Spigot-db6de12-18fbb24]
        at org.bukkit.craftbukkit.v1_8_R3.inventory.CraftInventory.setItem(CraftInventory.java:79) ~[spigot-1.11.2.jar:git-Spigot-db6de12-18fbb24]
        at me.MathiasMC.Report.gui.ReportsGUI.createGUI(ReportsGUI.java:80) ~[?:?]
        at me.MathiasMC.Report.gui.ReportsGUI.onClick(ReportsGUI.java:139) ~[?:?]
        at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[?:1.8.0_121]
        at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source) ~[?:1.8.0_121]
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source) ~[?:1.8.0_121]
        at java.lang.reflect.Method.invoke(Unknown Source) ~[?:1.8.0_121]
        at org.bukkit.plugin.java.JavaPluginLoader$1.execute(JavaPluginLoader.java:306) ~[spigot-1.11.2.jar:git-Spigot-db6de12-18fbb24]
        ... 15 more

 

I gave you the code you need

Verstuurd vanaf mijn A0001 met Tapatalk

 

I still gets this error when i go to page 2
i use your method

Code:

at java.lang.Thread.run(Unknown Source) [?:1.8.0_121]
Caused by: java.lang.IndexOutOfBoundsException: Index: 53, Size: 45
at java.util.ArrayList.rangeCheck(Unknown Source) ~[?:1.8.0_121]

full class

Code:

int page = 1;
   
   
    public void createGUI(Player p) {
        if (Config.getInstance().getData().contains("Reports")) {
            ArrayList<ItemStack> items = new ArrayList<ItemStack>();
        for (String z : Config.getInstance().getData().getConfigurationSection("Reports").getKeys(false)) {
              ItemStack item = new ItemStack(Material.PAPER, 1);
              ItemMeta meta = item.getItemMeta();
              meta.setDisplayName(Config.getInstance().getData().getString("Reports" + "." + z + "." + "Reporter") + "´s report" + " ID: " + z);
              List<String> lore = new ArrayList<String>();
              lore.add("Reporter: " + Config.getInstance().getData().getString("Reports" + "." + z + "." + "Reporter"));
              lore.add("Reported: " + Config.getInstance().getData().getString("Reports" + "." + z + "." + "Reported"));
              lore.add("Reason: " + Config.getInstance().getData().getString("Reports" + "." + z + "." + "Reason"));
              lore.add("Status: " + Config.getInstance().getData().getString("Reports" + "." + z + "." + "Status"));
              meta.setLore(lore);
              item.setItemMeta(meta);
             
              items.add(item);
             
              Inventory inventory = Bukkit.createInventory(null, 54, "Reports " + "Page: " + page);
              int amtPages = 52;
              int index = page * amtPages - amtPages;
              int endIndex = Math.min(index+amtPages,items.size());
             
              for (; index < endIndex; index++)
              {
                  inventory.setItem(index, item);
              }
              if (page == 1) {
                  ItemStack nextpage = new ItemStack(Material.ARROW, 1);
                    ItemMeta nextpagemeta = nextpage.getItemMeta();
                    nextpagemeta.setDisplayName("Next Page");
                    nextpage.setItemMeta(nextpagemeta);
                    inventory.setItem(53, nextpage);
              }
             
             
              p.openInventory(inventory);
        }
        }
    }
   
    @EventHandler
      public void onClick(InventoryClickEvent e) {
        if (e.getCurrentItem() == null || (e.getCurrentItem().getType() == Material.AIR)) {
            return;
            }
        if (e.getCurrentItem().hasItemMeta()) {
        for (String z : Config.getInstance().getData().getConfigurationSection("Reports").getKeys(false)) {
        if (e.getInventory().getName().equalsIgnoreCase(Config.getInstance().getData().getString("Reports" + "." + z + "." + "Reporter") + "´s report" + " ID: " + z)) {
            e.setCancelled(true);
            if (e.getCurrentItem().getItemMeta().getDisplayName().equalsIgnoreCase("Delete Report")) {
                Config.getInstance().getData().set("Reports" + "." + z, null);
                Config.getInstance().saveData();
                e.getWhoClicked().sendMessage("Report Deleted ID: " + z);
                e.getWhoClicked().closeInventory();
            }
            if (e.getCurrentItem().getItemMeta().getDisplayName().equalsIgnoreCase("Go Back")) {
                e.getWhoClicked().closeInventory();
                Player player = (Player) e.getWhoClicked();
                createGUI(player);
            }
            if (e.getCurrentItem().getItemMeta().getDisplayName().equalsIgnoreCase("Reporter: " + Config.getInstance().getData().getString("Reports" + "." + z + "." + "Reporter"))) {
                return;
            }
            if (e.getCurrentItem().getItemMeta().getDisplayName().equalsIgnoreCase("Reported: " + Config.getInstance().getData().getString("Reports" + "." + z + "." + "Reported"))) {
                return;
            }
        }
        }
        }
        if (e.getInventory().getName().equalsIgnoreCase("Reports " + "Page: " + page)) {
            if (e.getCurrentItem() == null || (e.getCurrentItem().getType() == Material.AIR)) {
                return;
                }
            if (e.getCurrentItem().hasItemMeta()) {
                if (e.getCurrentItem().getItemMeta().getDisplayName().equalsIgnoreCase("Next Page")) {
                    page = 2;
                    Player player = (Player) e.getWhoClicked();
                    player.closeInventory();
                    createGUI(player);
                }
            for (String z : Config.getInstance().getData().getConfigurationSection("Reports").getKeys(false)) {
            if (e.getCurrentItem().getItemMeta().getDisplayName().equalsIgnoreCase(Config.getInstance().getData().getString("Reports" + "." + z + "." + "Reporter") + "´s report" + " ID: " + z)) {
                e.setCancelled(true);
                Inventory IDMain = Bukkit.createInventory(null, 9, Config.getInstance().getData().getString("Reports" + "." + z + "." + "Reporter") + "´s report" + " ID: " + z);
               
               
                ItemStack deletereport = new ItemStack(Material.BARRIER, 1);
                ItemMeta deletereportmeta = deletereport.getItemMeta();
                deletereportmeta.setDisplayName("Delete Report");
                deletereport.setItemMeta(deletereportmeta);
                IDMain.setItem(8, deletereport);
               
               
                ItemStack goback = new ItemStack(Material.SIGN, 1);
                ItemMeta gobackmeta = goback.getItemMeta();
                gobackmeta.setDisplayName("Go Back");
                goback.setItemMeta(gobackmeta);
                IDMain.setItem(7, goback);
               
               
                ItemStack playerreporter = new ItemStack(Material.SKULL_ITEM, 1, (byte) 3);
                SkullMeta playerreportermeta = (SkullMeta) playerreporter.getItemMeta();
                playerreportermeta.setOwner(Config.getInstance().getData().getString("Reports" + "." + z + "." + "Reporter"));
                playerreportermeta.setDisplayName("Reporter: " + Config.getInstance().getData().getString("Reports" + "." + z + "." + "Reporter"));
                List<String> playerreporterlore = new ArrayList<String>();
                Player playerreporterplayer = Bukkit.getPlayerExact(Config.getInstance().getData().getString("Reports" + "." + z + "." + "Reporter"));
                if (playerreporterplayer == null) {
                    playerreporterlore.add("Player is offline.");
                } else {
                    playerreporterlore.add("Player is online.");
                }
                playerreportermeta.setLore(playerreporterlore);
                playerreporter.setItemMeta(playerreportermeta);
                IDMain.setItem(0, playerreporter);
               
               
                ItemStack playerreported = new ItemStack(Material.SKULL_ITEM, 1, (byte) 3);
                SkullMeta playerreportedmeta = (SkullMeta) playerreported.getItemMeta();
                playerreportedmeta.setOwner(Config.getInstance().getData().getString("Reports" + "." + z + "." + "Reported"));
                playerreportedmeta.setDisplayName("Reported: " + Config.getInstance().getData().getString("Reports" + "." + z + "." + "Reported"));
                List<String> playerreportedlore = new ArrayList<String>();
                Player playerreportedplayer = Bukkit.getPlayerExact(Config.getInstance().getData().getString("Reports" + "." + z + "." + "Reported"));
                if (playerreportedplayer == null) {
                    playerreportedlore.add("Player is offline.");
                } else {
                    playerreportedlore.add("Player is online.");
                }
                playerreportedmeta.setLore(playerreportedlore);
                playerreported.setItemMeta(playerreportedmeta);
                IDMain.setItem(1, playerreported);
               
               
                ItemStack message = new ItemStack(Material.PAPER, 1);
                ItemMeta messagemeta = message.getItemMeta();
                messagemeta.setDisplayName("Message:");
                List<String> messagelore = new ArrayList<String>();
                messagelore.add(Config.getInstance().getData().getString("Reports" + "." + z + "." + "Reason"));
                messagemeta.setLore(messagelore);
                message.setItemMeta(messagemeta);
                IDMain.setItem(4, message);
               
               
                e.getWhoClicked().openInventory(IDMain);
            }
          }
        }
    }
    }
}

 

@mathkot59
you have a lot of duplicate code. Never copy and paste. If you use a series of lines over and over again (Creating itemstacks), create a method specifically for that function.

53 is larger than the inventory's size. Remove this line, or change "53" to the size of the inventory -1.

 

@mathkot59 I'm pretty sure Zombie_Striker said this about 2 times already, you're slot for adding items has '53' when that is over the limit for the slots. Start from 0(which is equal to 1) and count where the item would be.
What your doing:

Code:

if (page == 1) {
                  ItemStack nextpage = new ItemStack(Material.ARROW, 1);
                    ItemMeta nextpagemeta = nextpage.getItemMeta();
                    nextpagemeta.setDisplayName("Next Page");
                    nextpage.setItemMeta(nextpagemeta);
                    inventory.setItem(53, nextpage);

^ See that? Change 53 to an existing slot.

 

The next page item is showing up in the gui
here is what happening
https://gyazo.com/b8b6071fb5e7dc66a4b8ca358accebe8

the error thrown

Code:

org.bukkit.event.EventException
        at org.bukkit.plugin.java.JavaPluginLoader$1.execute(JavaPluginLoader.java:310) ~[spigot-1.11.2.jar:git-Spigot-db6de12-18fbb24]
        at org.bukkit.plugin.RegisteredListener.callEvent(RegisteredListener.java:62) ~[spigot-1.11.2.jar:git-Spigot-db6de12-18fbb24]
        at org.bukkit.plugin.SimplePluginManager.fireEvent(SimplePluginManager.java:502) [spigot-1.11.2.jar:git-Spigot-db6de12-18fbb24]
        at org.bukkit.plugin.SimplePluginManager.callEvent(SimplePluginManager.java:487) [spigot-1.11.2.jar:git-Spigot-db6de12-18fbb24]
        at net.minecraft.server.v1_8_R3.PlayerConnection.a(PlayerConnection.java:1630) [spigot-1.11.2.jar:git-Spigot-db6de12-18fbb24]
        at net.minecraft.server.v1_8_R3.PacketPlayInWindowClick.a(SourceFile:31) [spigot-1.11.2.jar:git-Spigot-db6de12-18fbb24]
        at net.minecraft.server.v1_8_R3.PacketPlayInWindowClick.a(SourceFile:9) [spigot-1.11.2.jar:git-Spigot-db6de12-18fbb24]
        at net.minecraft.server.v1_8_R3.PlayerConnectionUtils$1.run(SourceFile:13) [spigot-1.11.2.jar:git-Spigot-db6de12-18fbb24]
        at java.util.concurrent.Executors$RunnableAdapter.call(Unknown Source) [?:1.8.0_121]
        at java.util.concurrent.FutureTask.run(Unknown Source) [?:1.8.0_121]
        at net.minecraft.server.v1_8_R3.SystemUtils.a(SourceFile:44) [spigot-1.11.2.jar:git-Spigot-db6de12-18fbb24]
        at net.minecraft.server.v1_8_R3.MinecraftServer.B(MinecraftServer.java:715) [spigot-1.11.2.jar:git-Spigot-db6de12-18fbb24]
        at net.minecraft.server.v1_8_R3.DedicatedServer.B(DedicatedServer.java:374) [spigot-1.11.2.jar:git-Spigot-db6de12-18fbb24]
        at net.minecraft.server.v1_8_R3.MinecraftServer.A(MinecraftServer.java:654) [spigot-1.11.2.jar:git-Spigot-db6de12-18fbb24]
        at net.minecraft.server.v1_8_R3.MinecraftServer.run(MinecraftServer.java:557) [spigot-1.11.2.jar:git-Spigot-db6de12-18fbb24]
        at java.lang.Thread.run(Unknown Source) [?:1.8.0_121]
Caused by: java.lang.ArrayIndexOutOfBoundsException: 54
        at org.bukkit.craftbukkit.v1_8_R3.inventory.CraftInventoryCustom$MinecraftInventory.setItem(CraftInventoryCustom.java:105) ~[spigot-1.11.2.jar:git-Spigot-db6de12-18fbb24]
        at org.bukkit.craftbukkit.v1_8_R3.inventory.CraftInventory.setItem(CraftInventory.java:79) ~[spigot-1.11.2.jar:git-Spigot-db6de12-18fbb24]
        at me.MathiasMC.Report.gui.ReportsGUI.createGUI(ReportsGUI.java:59) ~[?:?]
        at me.MathiasMC.Report.gui.ReportsGUI.onClick(ReportsGUI.java:116) ~[?:?]
        at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[?:1.8.0_121]
        at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source) ~[?:1.8.0_121]
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source) ~[?:1.8.0_121]
        at java.lang.reflect.Method.invoke(Unknown Source) ~[?:1.8.0_121]
        at org.bukkit.plugin.java.JavaPluginLoader$1.execute(JavaPluginLoader.java:306) ~[spigot-1.11.2.jar:git-Spigot-db6de12-18fbb24]
        ... 15 more

full code

Code:

import java.util.ArrayList;
import java.util.List;

import org.bukkit.Bukkit;
import org.bukkit.Material;
import org.bukkit.entity.Player;
import org.bukkit.event.EventHandler;
import org.bukkit.event.Listener;
import org.bukkit.event.inventory.InventoryClickEvent;
import org.bukkit.inventory.Inventory;
import org.bukkit.inventory.ItemStack;
import org.bukkit.inventory.meta.ItemMeta;
import org.bukkit.inventory.meta.SkullMeta;

import me.MathiasMC.Report.Report;
import me.MathiasMC.Report.utils.Config;

public class ReportsGUI implements Listener {
  
    static ReportsGUI instance = new ReportsGUI();
    
      public static ReportsGUI getInstance()
      {
        return instance;
      }
  
    public void createGUI(Player p) {
        if (Config.getInstance().getData().contains("Reports")) {
            ArrayList<ItemStack> items = new ArrayList<ItemStack>();
            if (!Report.instance.pageID.containsKey(p.getPlayer().getUniqueId().toString())) {
                Report.instance.pageID.put(p.getPlayer().getUniqueId().toString(), 1);
            }
        for (String z : Config.getInstance().getData().getConfigurationSection("Reports").getKeys(false)) {
              ItemStack item = new ItemStack(Material.PAPER, 1);
              ItemMeta meta = item.getItemMeta();
              meta.setDisplayName(Config.getInstance().getData().getString("Reports" + "." + z + "." + "Reporter") + "´s report" + " ID: " + z);
              List<String> lore = new ArrayList<String>();
              lore.add("Reporter: " + Config.getInstance().getData().getString("Reports" + "." + z + "." + "Reporter"));
              lore.add("Reported: " + Config.getInstance().getData().getString("Reports" + "." + z + "." + "Reported"));
              lore.add("Reason: " + Config.getInstance().getData().getString("Reports" + "." + z + "." + "Reason"));
              lore.add("Status: " + Config.getInstance().getData().getString("Reports" + "." + z + "." + "Status"));
              meta.setLore(lore);
              item.setItemMeta(meta);
            
              items.add(item);
            
              int ID = Report.instance.pageID.get(p.getPlayer().getUniqueId().toString());
            
              Inventory inventory = Bukkit.createInventory(null, 54, "Reports " + "Page: " + Report.instance.pageID.get(p.getPlayer().getUniqueId().toString()));
              int amtPages = 52;
              int index = ID * amtPages - amtPages;
              int endIndex = Math.min(index+amtPages,items.size());
            
              for (; index < endIndex; index++)
              {
                  inventory.setItem(index, item);
              }
              if (ID == 1) {
                  ItemStack nextpage = new ItemStack(Material.ARROW, 1);
                    ItemMeta nextpagemeta = nextpage.getItemMeta();
                    nextpagemeta.setDisplayName("Next Page");
                    nextpage.setItemMeta(nextpagemeta);
                    inventory.setItem(53, nextpage);
              }
            
            
              p.openInventory(inventory);
        }
        }
    }
  
    @EventHandler
      public void onClick(InventoryClickEvent e) {
        if (e.getCurrentItem() == null || (e.getCurrentItem().getType() == Material.AIR)) {
            return;
            }
        e.setCancelled(true);
        if (e.getCurrentItem().hasItemMeta()) {
        for (String z : Config.getInstance().getData().getConfigurationSection("Reports").getKeys(false)) {
        if (e.getInventory().getName().equalsIgnoreCase(Config.getInstance().getData().getString("Reports" + "." + z + "." + "Reporter") + "´s report" + " ID: " + z)) {
            if (e.getCurrentItem().getItemMeta().getDisplayName().equalsIgnoreCase("Delete Report")) {
                Config.getInstance().getData().set("Reports" + "." + z, null);
                Config.getInstance().saveData();
                e.getWhoClicked().sendMessage("Report Deleted ID: " + z);
                e.getWhoClicked().closeInventory();
            }
            if (e.getCurrentItem().getItemMeta().getDisplayName().equalsIgnoreCase("Go Back")) {
                e.getWhoClicked().closeInventory();
                Player player = (Player) e.getWhoClicked();
                createGUI(player);
            }
            if (e.getCurrentItem().getItemMeta().getDisplayName().equalsIgnoreCase("Reporter: " + Config.getInstance().getData().getString("Reports" + "." + z + "." + "Reporter"))) {
                return;
            }
            if (e.getCurrentItem().getItemMeta().getDisplayName().equalsIgnoreCase("Reported: " + Config.getInstance().getData().getString("Reports" + "." + z + "." + "Reported"))) {
                return;
            }
        }
        }
        }
        Player player = (Player) e.getWhoClicked();
        int ID = Report.instance.pageID.get(player.getPlayer().getUniqueId().toString());
        if (e.getInventory().getName().equalsIgnoreCase("Reports " + "Page: " + ID)) {
            if (e.getCurrentItem() == null || (e.getCurrentItem().getType() == Material.AIR)) {
                return;
                }
            if (e.getCurrentItem().hasItemMeta()) {
                if (e.getCurrentItem().getItemMeta().getDisplayName().equalsIgnoreCase("Next Page")) {
                    int set = 2;
                    Report.instance.pageID.remove(player.getPlayer().getUniqueId().toString());
                    Report.instance.pageID.put(player.getPlayer().getUniqueId().toString(), set);
                    player.closeInventory();
                    createGUI(player);
                    player.sendMessage("ID " + Report.instance.pageID.get(player.getPlayer().getUniqueId().toString()));
                }
            for (String z : Config.getInstance().getData().getConfigurationSection("Reports").getKeys(false)) {
            if (e.getCurrentItem().getItemMeta().getDisplayName().equalsIgnoreCase(Config.getInstance().getData().getString("Reports" + "." + z + "." + "Reporter") + "´s report" + " ID: " + z)) {
                Inventory IDMain = Bukkit.createInventory(null, 9, Config.getInstance().getData().getString("Reports" + "." + z + "." + "Reporter") + "´s report" + " ID: " + z);
              
              
                ItemStack deletereport = new ItemStack(Material.BARRIER, 1);
                ItemMeta deletereportmeta = deletereport.getItemMeta();
                deletereportmeta.setDisplayName("Delete Report");
                deletereport.setItemMeta(deletereportmeta);
                IDMain.setItem(8, deletereport);
              
              
                ItemStack goback = new ItemStack(Material.SIGN, 1);
                ItemMeta gobackmeta = goback.getItemMeta();
                gobackmeta.setDisplayName("Go Back");
                goback.setItemMeta(gobackmeta);
                IDMain.setItem(7, goback);
              
              
                ItemStack playerreporter = new ItemStack(Material.SKULL_ITEM, 1, (byte) 3);
                SkullMeta playerreportermeta = (SkullMeta) playerreporter.getItemMeta();
                playerreportermeta.setOwner(Config.getInstance().getData().getString("Reports" + "." + z + "." + "Reporter"));
                playerreportermeta.setDisplayName("Reporter: " + Config.getInstance().getData().getString("Reports" + "." + z + "." + "Reporter"));
                List<String> playerreporterlore = new ArrayList<String>();
                Player playerreporterplayer = Bukkit.getPlayerExact(Config.getInstance().getData().getString("Reports" + "." + z + "." + "Reporter"));
                if (playerreporterplayer == null) {
                    playerreporterlore.add("Player is offline.");
                } else {
                    playerreporterlore.add("Player is online.");
                }
                playerreportermeta.setLore(playerreporterlore);
                playerreporter.setItemMeta(playerreportermeta);
                IDMain.setItem(0, playerreporter);
              
              
                ItemStack playerreported = new ItemStack(Material.SKULL_ITEM, 1, (byte) 3);
                SkullMeta playerreportedmeta = (SkullMeta) playerreported.getItemMeta();
                playerreportedmeta.setOwner(Config.getInstance().getData().getString("Reports" + "." + z + "." + "Reported"));
                playerreportedmeta.setDisplayName("Reported: " + Config.getInstance().getData().getString("Reports" + "." + z + "." + "Reported"));
                List<String> playerreportedlore = new ArrayList<String>();
                Player playerreportedplayer = Bukkit.getPlayerExact(Config.getInstance().getData().getString("Reports" + "." + z + "." + "Reported"));
                if (playerreportedplayer == null) {
                    playerreportedlore.add("Player is offline.");
                } else {
                    playerreportedlore.add("Player is online.");
                }
                playerreportedmeta.setLore(playerreportedlore);
                playerreported.setItemMeta(playerreportedmeta);
                IDMain.setItem(1, playerreported);
              
              
                ItemStack message = new ItemStack(Material.PAPER, 1);
                ItemMeta messagemeta = message.getItemMeta();
                messagemeta.setDisplayName("Message:");
                List<String> messagelore = new ArrayList<String>();
                messagelore.add(Config.getInstance().getData().getString("Reports" + "." + z + "." + "Reason"));
                messagemeta.setLore(messagelore);
                message.setItemMeta(messagemeta);
                IDMain.setItem(4, message);
              
              
                e.getWhoClicked().openInventory(IDMain);
            }
          }
        }
    }
    }
}

 

I'm starting to feel lime I'm repeating myself. Always make sure the the index are less than the size of the inventory. Currently, when you get to the second page, index becomes equal to 52*2-52, which is 104, which is larger than 52.

To fix this, make sure index is set to 0 instead of that value.

 

if i set the index to always == 0 the items is just being copied from page 1 to page 2
i want if page 1 is full it uses page 2 for the rest

 

@mathkot59
But, the index should be independent of the page. The index should only be in change of where the item gets placed in the inventory, not what item is put there.

Edit: The index does not have anything to do with what is put there. The variable item has nothing to do with the index, because index is created after the item. Set index to 0.

 

@Zombie_Striker
Yes! i works now but only one problem the if the page 1 is full and i go to page 2 the items starts from slot 45 i will have i to start in slot 1

Here's what happens
https://gyazo.com/56947d6d9b7e91b02c058faf619d41ae


code

Code:

public void createGUI(Player p) {
        if (Config.getInstance().getData().contains("Reports")) {
            ArrayList<ItemStack> items = new ArrayList<ItemStack>();
            if (!Report.instance.pageID.containsKey(p.getPlayer().getUniqueId().toString())) {
                Report.instance.pageID.put(p.getPlayer().getUniqueId().toString(), 1);
            }
        for (String z : Config.getInstance().getData().getConfigurationSection("Reports").getKeys(false)) {
              ItemStack item = new ItemStack(Material.PAPER, 1);
              ItemMeta meta = item.getItemMeta();
              meta.setDisplayName(Config.getInstance().getData().getString("Reports" + "." + z + "." + "Reporter") + "´s report" + " ID: " + z);
              List<String> lore = new ArrayList<String>();
              lore.add("Reporter: " + Config.getInstance().getData().getString("Reports" + "." + z + "." + "Reporter"));
              lore.add("Reported: " + Config.getInstance().getData().getString("Reports" + "." + z + "." + "Reported"));
              lore.add("Reason: " + Config.getInstance().getData().getString("Reports" + "." + z + "." + "Reason"));
              lore.add("Status: " + Config.getInstance().getData().getString("Reports" + "." + z + "." + "Status"));
              meta.setLore(lore);
              item.setItemMeta(meta);
            
              items.add(item);
            
              int ID = Report.instance.pageID.get(p.getPlayer().getUniqueId().toString());
            
              Inventory inventory = Bukkit.createInventory(null, 54, "Reports " + "Page: " + Report.instance.pageID.get(p.getPlayer().getUniqueId().toString()));
              int amtPages = 44;
              index = ID * amtPages - amtPages;
              if (ID == 1) {
                  ItemStack nextpage = new ItemStack(Material.ARROW, 1);
                    ItemMeta nextpagemeta = nextpage.getItemMeta();
                    nextpagemeta.setDisplayName("Next Page");
                    nextpage.setItemMeta(nextpagemeta);
                    inventory.setItem(53, nextpage);
              }
              int endIndex = Math.min(index+amtPages,items.size());
            
              for (; index < endIndex; index++)
              {
                  inventory.setItem(index, items.get(index));
              }
            
            
            
              p.openInventory(inventory);
        }
    }
    }

 

Make it like this:


inventory.setItem(index%amtPages, items.get(index));

 

@MrGeneralQ
@Zombie_Striker
Thanks!