I have a Bug with my GUI Container...I want to make a Machine but there is a Bug with the Slots. I have a little Video from the Bug, here you can see:

And here is the Code:

TileEntity:

public class TileEntityChemicalMixer extends TileEntity{

public InventoryBasic INVENTORY;

public TileEntityChemicalMixer(){
	INVENTORY = new InventoryBasic("Chemical Mixer", false, 3);
}

@Override
public void writeToNBT(NBTTagCompound compound) {
	super.writeToNBT(compound);

	NBTTagList list = new NBTTagList();

	for(int i = 0; i < INVENTORY.getSizeInventory(); i++){
		if(INVENTORY.getStackInSlot(i) != null){
			NBTTagCompound tag = new NBTTagCompound();
			tag.setByte("Slot", (byte) i);
			INVENTORY.getStackInSlot(i).writeToNBT(tag);
			list.appendTag(tag);
		}
	}

	compound.setTag("ItemStacks", list);
}

@Override
public void readFromNBT(NBTTagCompound compound) {
	super.readFromNBT(compound);
	NBTTagList list = compound.getTagList("ItemStacks", 10);
	this.INVENTORY = new InventoryBasic("Chemical Mixer", false, 3);
	for(int i = 0; i < list.tagCount(); i++){
		NBTTagCompound tag = list.getCompoundTagAt(i);
		byte b = tag.getByte("Slot");
		if(b >= 0 && b < INVENTORY.getSizeInventory()){
			INVENTORY.setInventorySlotContents(b, ItemStack.loadItemStackFromNBT(tag));
		}
	}
}

}

Container:

public class ContainerChemicalMixer extends Container{

private TileEntityChemicalMixer tileentiy;

public ContainerChemicalMixer(IInventory inv, TileEntityChemicalMixer tileentity) {
	this.tileentiy = tileentity;
	this.addSlotToContainer(new Slot(inv, 0, 30, 17));
	this.addSlotToContainer(new Slot(inv, 0, 130, 17));

    // Player Inventory, Slot 9-35, Slot IDs 9-35
    for (int y = 0; y < 3; ++y) {
        for (int x = 0; x < 9; ++x) {
            this.addSlotToContainer(new Slot(inv, x + y * 9 + 9, 8 + x * 18, 84 + y * 18));
        }
    }

    // Player Inventory, Slot 0-8, Slot IDs 36-44
    for (int x = 0; x < 9; ++x) {
        this.addSlotToContainer(new Slot(inv, x, 8 + x * 18, 142));
    }
}

@Override
public boolean canInteractWith(EntityPlayer playerIn) {
	return true;
}

}

And GUI:

public class GuiChemicalMixer extends GuiContainer{

public static final ResourceLocation BACKGROUND = new ResourceLocation(Main.MODID + ":textures/gui/chemicalmixergui.png");

public GuiChemicalMixer(Container inventorySlotsIn) {
	super(inventorySlotsIn);
	this.ySize = 166;
	this.xSize = 176;
}

@Override
protected void drawGuiContainerBackgroundLayer(float partialTicks, int mouseX, int mouseY) {
	mc.renderEngine.bindTexture(BACKGROUND);
	int k = (this.width - this.xSize) / 2;
	int l = (this.height - this.ySize) / 2;
	drawTexturedModalRect(k, l, 0, 0, xSize, ySize);
}

}

Issue is here:

	this.addSlotToContainer(new Slot(inv, 0, 30, 17));
	this.addSlotToContainer(new Slot(inv, 0, 130, 17));

    // Player Inventory, Slot 0-8, Slot IDs 36-44
    for (int x = 0; x < 9; ++x) {
        this.addSlotToContainer(new Slot(inv, x, 8 + x * 18, 142));
    }

The Slot takes in the parameters IInventory, Index, xPos, yPos.

You have to declare the two top slots as something else. You declare the player's hotbar with the id's 0->8, not as the commented 36-44. The player's inventory 9->35. I'd recommend setting the two "main" slots to 36 & 37 respectively.

Ahhh thanks...wow that was a bit stupid