Quick questions about Gideros&Lua

rrraptor

How to properly use second parameter to Core.class()?
I have a hierarchy like: Sprite <- foo <- bar <- abc
I did this:<pre class="CodeBlock">

foo = Core.class(Sprite)   function foo:init(param) assert(param ~= nil, "Overide me") self.param = param print("Output from foo", self.param) end   bar = Core.class(foo)   function bar:init(param) print("Output from bar", self.param) end   function bar:ok() print("bar ok") end   abc = Core.class(bar, function(a) return a end)   function bar:init(param) print("Output from abc", self.param) end   local a = abc.new("yo") a:ok()

Ouput:

Output from foo yo
Output from abc yo
bar ok

Why there is no "Output from bar"?

hgy29

I see two definitions for bar:init() but none for abc:init() ...

rrraptor

Omg, Im so stupid...
Anyways, any info about 2d args Core.class([base, args]) parameter?

hgy29

the second arg should be a function that will returns the args to pass to the base class when constructing it

rrraptor

How TextField's "h" parameter in layout properties works?
I tried different values (big, small, negative), but seems like its competently ignored. Correct me if Im wrong.

hgy29

It is only used if you want to center vertically or bottom align your text

rrraptor

So it shoud not work with TLF_CENTER? And if so, I need to center it by myself?

Code:

Label = Core.class(TextField, function(t) return nil,t.text,"" end)   function Label:init(params) self:setLayout{ flags = FontBase.TLF_CENTER|FontBase.TLF_REF_TOP, w = params.w, h = params.h or 0 } self.ax = params.ax or 0 self.ay = params.ay or 0 self.offsetX = params.offsetX or 0 self.offsetY = params.offsetY or 0 self:setPosition(self.offsetX, self.offsetY) end   local w, h = 70, 200 local scale = 2   local l = Label.new({text="Sample multiline text", w = w, h = h}) l:setTextColor(0xffffff) l:setScale(scale) l:setPosition(100, 100) stage:addChild(l)   local px = Pixel.new(0xff0000, 0.3, w*scale, h*scale) px:setPosition(l:getPosition()) stage:addChild(px)

Edit: turns out that TLF_CENTER is horizontal center, and I shoud use TLF_VCENTER also, silly me

flags = FontBase.TLF_REF_TOP|FontBase.TLF_VCENTER|FontBase.TLF_CENTER

rrraptor

Is it posible to inherit meta methods like __tostring() ?

Lets say I have

GlobalID = 0   foo = Core.class() function foo:init() GlobalID += 1 self.id = GlobalID end function foo:__tostring() return string.format("Object [%i]", self.id) end   bar = Core.class(foo) function bar:init() end   local a = foo.new() print(a) -- > give us "Object [1]" local b = bar.new() print(b) -- > give us "table: xxxxxxxx"

But I want to print ID for bar object too.

I have one solution, but I dont like it, maybe ther is more elegant way of doing this?

GlobalID = 0   foo = Core.class() function foo:init() GlobalID += 1 self.id = GlobalID self:gen() end function foo:gen() local t = getmetatable(self) t.__tostring = function(v) return string.format("Object [%i]", v.id) end setmetatable(self, t) end   bar = Core.class(foo) function bar:init() self:gen() end   local a = foo.new() print(a) -- > "Object [1]" local b = bar.new() print(b) -- > "Object [2]"