I don't understand my error

Questions
1

This error happens. Can someon plz explain me it?

AllDiscussions:13: bad argument #1 to 'insert' (table expected, got nil)
stack traceback:
	[C]: in function 'table.insert'
	AllDiscussions:13: in method 'addDiscussion'
	CreateTopicPage:120: in method 'post'
	CreateTopicPage:61: in method 'touched'
	Main:56: in function 'touched'

I don’t understand why he isn’t recognising my table? The table is a self an is located in init.

2

Here is the code:

AllDiscussions = class()
-- Nothing more the General

function AllDiscussions:init()
    self.y = 0
    self.touch = false
    self.dynamic = {DiscussionType("Test Topic", "General", "TokOut", 280, [[This topic includes a line<break>break because it is too long for<break>the positions. Ill try to fix<break>all bugs, because with bugs there<break>is no fun]])}
    self.p = 0
end

function AllDiscussions:addDiscussion(name, category, own, data)
    local p = self.p
    table.insert(self.dynamic, DiscussionType(name, category, own, p, data))
end

function AllDiscussions:draw()
    self.p = 280 - #self.dynamic * 110
    -- Discussions/Draw them
    self.creatediscussion = CreateTopic(self.y + 500)
    self.creatediscussion:draw()
    self.settings = SettingBox(self.y + 390)
    self.settings:draw()
    for _,d in pairs(self.dynamic) do d:draw() end
end

function AllDiscussions:touched(t)
    -- Action List
    self.creatediscussion:touched(t)
    self.settings:touched(t)
    -- Main Action
    if t.state == ENDED then
        self.touch = false
        local currentY = 0
    else
        if t.y < 650 then
            self.touch = true
            local currentY = t.y
            translate(0, currentY)
            if currentY > self.y then
                self.y = self.y + t.deltaY/2
            else
                self.y = self.y - t.deltaY/2
            end
            translate(0, -currentY)
            for _,d in pairs(self.dynamic) do
                d:touched(t)
            end
        end
    end
end

-- This function is nil
function AllDiscussions:keyboard(key)end
3

If someone asks I’m working on Codea Talk in Codea

4

can you post the code that creates the instance of AllDiscussions, (ie something = AllDiscussions(args) and the code that calls the addDiscussion method in createTopicPage please.

5

@yojimbo2000, this is the code where I add a new discussion:

function CreateTopicPage:post()
    if string.len(self.text.message)==0 or string.len(self.text.title)==0 or self.category==nil then
        print("Failed: Title, body or nil category")
        self.selected = 1
    else
        local t = title
        local b = body
        local c = cat
        currentPage = AllDiscussions()
        AllDiscussions:addDiscussion(t, c, "Non User", b)
    end
end
6

Wait, here I had this code. That was from another project:


function CreateTopicPage:post()
    if string.len(self.text.message)==0 or string.len(self.text.title)==0 or self.category==nil then
        print("Failed: Title, body or nil category")
        self.selected = 1
    else
        local t = self.text.title
        local b = self.text.message
        local c = self.category
        currentPage = AllDiscussions()
        AllDiscussions:addDiscussion(t, c, "Non User", b)
    end
end

--[[
AllDiscussions:13: bad argument #1 to 'insert' (table expected, got nil)
stack traceback:
	[C]: in function 'table.insert'
	AllDiscussions:13: in method 'addDiscussion'
	CreateTopicPage:120: in method 'post'
	CreateTopicPage:61: in method 'touched'
	Main:56: in function 'touched'
]]
7

You need to call a method on an instance of a class, so it should be currentPage:addDiscussion(), not AllDiscussions:addDiscussion() otherwise, the method won’t be able to access the correct self variable. That’s why instead of seeing a table, addDiscussion just found nil.You need to make sure you do this each time you call a class method.

8

@TokOut - please go back and read the explanations and tutorials about classes. You don’t know enough yet to use them properly.

9

Thank you!