Btn is a simple and lite button library for Codea

# Btn 0.0.4

automatically created by Required (0.0.28) from HyroVitalyProtago
hyrovitalyprotago@gmail.com
https://gist.github.com/7802bd00e7d56d480379

Btn.lua

return (function()
    local Btn = class()
    
    -- todo
    
    -- Advanced
    -- size = "lg" | "sm" | "xs" | "default",
    
    -- defined by width | height | width,height | fontSize | width,height,fontSize
    -- width => fontSize max + height auto 
    -- height => fontSize max + width auto 
    -- width,height => fontSize max
    -- fontSize => width,height auto
    -- width,height,fontSize => width,height max, favorite fontSize (if too large => adjusted)

    local styles = {
        primary = {
            background = color(39, 78, 191),
            fill = color(220),
            active = {
                background = color(19, 58, 171)
            }
        },
        success = {
            background = color(80, 210, 97),
            fill = color(220),
            active = {
                background = color(60, 190, 77),
            }
        },
        info = {
            background = color(79, 175, 208),
            fill = color(220),
            active = {
                background = color(59, 155, 188),
            }
        },
        warning = {
            background = color(207, 147, 40),
            fill = color(220),
            active = {
                background = color(187, 127, 20),
            }
        },
        danger = {
            background = color(180, 74, 57),
            fill = color(220),
            active = {
                background = color(160, 54, 37),
            }
        },
        link = {
            noBackground = true,
            noStroke = true,
            fill = color(46, 108, 152),
            active = {
                fill = color(6, 48, 92),
            }
        }
    }
    
    local default = setmetatable({
        mode = CENTER,
        font = "HelveticaNeue-Light",
        fontSize = 32,
        fill = color(20),
        background = color(220),
        noBackground = false,
        stroke = color(20),
        noStroke = false,
        strokeWidth = 2,
        textWrapWidth = 0,
        active = {
            background = color(200)
        },
        shape = "rect",
        x = 0,
        y = 0,
        w = 200,
        h = 50,
        angle = 0, -- rotation
        padding = {
            h = 20, -- horizontal
            v = 5 -- vertical
        },
        onPress = function(self, touch) end,
        onRelease = function(self, touch) end
    }, {
        __call = function(default,a,k)
            return a[k] or (a.style and styles[a.style][k]) or (a.inherit and type(_G[k]) == "function" and _G[k]()) or default[k]
        end
    })
    
    local shapes = {
        rect = rect,
        circle = ellipse
    }
    
    local function backgroundContext(self)
        stroke(self.stroke)
        if self.noStroke then noStroke() else strokeWidth(self.strokeWidth) end
        if self.noBackground then noFill() else fill(self.background) end
    end
    
    local function textContext(self)
        font(self.font)
        fontSize(self.fontSize)
        fill(self.fill)
        textWrapWidth(self.textWrapWidth)
    end
    
    local function getWidthAndHeightFromFontSize(self)
        pushStyle()
        textContext(self)
        local w, h = textSize(self.text)
        popStyle()
        return w, h
    end
    
    local function adaptFontSize(self, valid) -- todo better
        local w, h
        local optimalFontSize = 0
        repeat
            pushStyle()
            self.fontSize = optimalFontSize
            textContext(self)
            w, h = textSize(self.text)
            popStyle()
            optimalFontSize = optimalFontSize + 1
        until not valid(optimalFontSize,w,h)
        return w,h
    end
    
    local function draw(self)
        backgroundContext(self)
        rectMode(CENTER)
        self.fshape(0, 0, self.w, self.h)
        
        textContext(self)
        text(self.text)
    end
    
    local function texture(s)
        local t = image(s.w, s.h)
        setContext(t)
        pushMatrix()
        translate(s.w*.5, s.h*.5)
        pushStyle()
        draw(s)
        popStyle()
        popMatrix()
        setContext()
        return t
    end
    
    local function meshBuild(w,h,t)
        local m = mesh()
        m:addRect(0,0,w,h)
        m.texture = t
        return m
    end
    
    local function decor(o,t)
        return setmetatable(table.deepcopy(t),{
            __index = function(tbl,k)
                return o[k]
            end
        })
    end
    
    local function convertCoord(x,s)
        return (math.type(x) == "float" and x*s) or (x < 0 and s-x) or x
    end
    
    function Btn:updateSize(args)
        local h,v = self.padding.h*2, self.padding.v*2
        if args.w or args.h then
            self.w = args.w or self.w
            self.h = args.h or self.h
            local nw, nh = adaptFontSize(self, function(ft,w,h)
                return w <= (args.w and args.w - h or w) and
                    h <= (args.h and args.h - v or h) and
                    ft <= (args.fontSize or ft)
            end)
            self.w = not args.w and nw + h or self.w
            self.h = not args.h and nh + v or self.h
        else
            self.w, self.h = getWidthAndHeightFromFontSize(self)
            self.w = self.w + h
            self.h = self.h + v
        end
        if self.shape == "circle" then
            self.w = math.max(self.w, self.h)
            self.h = self.w
        end
        self:updatePos()
        self:updateMesh()
    end
    
    function Btn:updatePos()
        self.realX, self.realY = convertCoord(self.x, WIDTH), convertCoord(self.y, HEIGHT)
        
        local tmp = vec2(self.w*.5, self.h*.5)
        self.ct = vec2(self.realX, self.realY) + (self.mode == CORNER and tmp or vec2(0,0)) -- center
        self.bl = self.ct - tmp -- bottomLeft
        self.tr = self.ct + tmp -- topRight
    end
    
    function Btn:updateMesh()
        self.textures = {
            default = texture(self),
            active = texture(decor(self, self.active))
        }
        self.mesh = meshBuild(self.w,self.h,self.textures[self.state])
    end
    
    function Btn:init(txt, args) -- inherit
        assert(txt and type(txt) == "string", "[Btn] first arg need to be a string")
        
        args = args or {}
        self.text = txt
        self.state = "default" -- "default" or "active"
        
        for k,_ in pairs(default) do
            self[k] = default(args, k)
        end
        
        self.fshape = shapes[self.shape] or _G[default.shape] -- inherited
        if self.shape == "circle" then
            self.inBounds = function(self, p) -- override in bounds for circle
                return self.ct:dist(vec2(p.x, p.y)) < self.w*.5
            end
        end
        
        
        self:updateSize(args) -- compute size
        
        -- automaticaly called by updateSize
        -- self:updatePos() -- pos: absolute, screen (width, height)
        -- self:updateMesh()
    end
    
    function Btn:draw()
        pushMatrix()
        translate(self.ct.x, self.ct.y)
        rotate(self.angle)
        self.mesh:draw()
        popMatrix()
    end
    
    function Btn:inBounds(p)
        return p.x >= self.bl.x and p.x <= self.tr.x and p.y >= self.bl.y and p.y <= self.tr.y
    end
    
    function Btn:touched(t)
        local touch = (vec2(t.x, t.y) - self.ct):rotate(-self.angle) + self.ct
        if self:inBounds(touch) then
            if not self:isActive() then self:onIn() end
            if t.state == BEGAN then
                self:pressed(touch)
            elseif t.state == ENDED then
                self:released(touch)
            end
        elseif self:isActive() then
            self:onOut()
        end
    end
    
    function Btn:changeState(state)
        self.state = state
        self.mesh.texture = self.textures[state] -- update texture
    end
    
    function Btn:clone()
        return Btn(self.text, {}) -- todo
    end
    
    function Btn:isActive() return self.state == "active" end
    function Btn:onIn() self:changeState("active") end
    function Btn:onOut() self:changeState("default") end
    
    function Btn:pressed(t) self:onPress(t) end
    function Btn:released(t) self:onOut() self:onRelease(t) end
    
    function Btn:orientationChanged(o) print("orientationChanged", o) end
    
    return Btn
end)

BtnGrp.lua

return (function()
    local BtnGrp = class()
    
    --[[ todo
        size = "lg" | "sm" | "xs" | "default",
        mode = CENTER, (UP, LEFT, RIGHT, BOTTOM, ...)
        background = ...,
        margin = 5, -- space between buttons
    ]]--
    
    local function convertCoord(x,s)
        return (math.type(x) == "float" and x*s) or (x < 0 and s-x) or x
    end
    
    function BtnGrp:init(group, args)
        assert(group and type(group) == "table", "[BtnGrp] first arg need to be a table")
        args = args or {}
        self.group = group
        
        self.align = args.align or "vertical"
        self.realX, self.realY = convertCoord(args.x or .5, WIDTH), convertCoord(args.y or .5, HEIGHT)
        
        local maxWidth, maxHeight = 0, 0
        
        -- move buttons to the right place
        local x, y = self.realX, self.realY
        for _,btn in ipairs(self.group) do
            maxWidth, maxHeight = math.max(maxWidth, btn.w), math.max(maxHeight, btn.h)
            
            btn.x, btn.y = math.floor(x), math.floor(y) -- todo setPos
            btn:updatePos()
            x, y = x + (self.align == "horizontal" and btn.w or 0), y + (self.align == "vertical" and btn.h or 0)
        end
        
        -- right size based on bigger size
        local newSize = { w = maxWidth, h = maxHeight }
        for _,btn in ipairs(self.group) do
            btn:updateSize(newSize) -- todo setSize
            btn:updateMesh()
        end
    end
    function BtnGrp:get(i) end -- todo
    function BtnGrp:insert(btn) end -- todo
    function BtnGrp:remove(btn) end -- todo
    function BtnGrp:draw()
        for _,btn in ipairs(self.group) do
            btn:draw()
        end
    end
    function BtnGrp:touched(t)
        for _,btn in ipairs(self.group) do
            btn:touched(t)
        end
    end
    function BtnGrp:orientationChanged(o)
        for _,btn in ipairs(self.group) do
            btn:orientationChanged(o)
        end
    end
    
    return BtnGrp
end)

Main.lua

-- Btn

local btns, map = {}
function setup()
    displayMode(FULLSCREEN)
    
    required.path 'Btn'
    
    local Btn = required.import 'Btn'
    local BtnGrp = required.import 'BtnGrp'
    
    local grp = {}
    local styles = {"Default", "Primary", "Success", "Info", "Warning", "Danger", "Link"}
    for _,v in pairs(styles) do
        grp[#grp+1] = Btn(v, {
            style = v ~= "Default" and v:lower()
        })
    end
    
    btns[#btns+1] = BtnGrp(grp, {
        x = .85,
        y = .3
    })
    
    local next_pos = (function(step)
        local i = step
        return function()
            local tmp = i
            i = i + step
            return tmp
        end
    end)
    
    local npl = next_pos(1/4)
    
    -- Circle
    btns[#btns+1] = Btn("GO", {
        x = .15,
        y = npl(),
        shape = "circle",
        background = color(0),
        fill = color(220),
        fontSize = 50,
        active = {
            background = color(255),
            fill = color(0)
        }
    })
    
    -- Circle with utf-8 icon
    btns[#btns+1] = Btn("\u{2654}", {
        x = .15,
        y = npl(),
        shape = "circle",
        background = color(0),
        fill = color(220),
        fontSize = 80,
        active = {
            background = color(255),
            fill = color(0)
        }
    })
    
    -- Rect with utf-8 icon
    btns[#btns+1] = Btn("\u{2663}", {
        x = .15,
        y = npl(),
        fontSize = 80,
        padding = { h=15, v=7 },
        active = {
            background = color(255),
            fill = color(0)
        }
    })
    
    -- with image
    --[[
    btns[#btns+1] = Btn(readImage("Cargo Bot:Star Filled"), {
        x = .15,
        y = npl(),
        shape = "circle",
        background = color(0),
        active = {
            background = color(255),
            fill = color(0)
        }
    })
    ]]--
    
    local npl = next_pos(1/6)

    -- width => fontSize max + height auto
    btns[#btns+1] = Btn("Fixed width", {
        x = .5,
        y = npl(),
        w = 100
    })
    
    -- height => fontSize max + width auto
    btns[#btns+1] = Btn("Fixed height", {
        x = .5,
        y = npl(),
        h = 75
    })
    
    -- width,height => fontSize max
    btns[#btns+1] = Btn("Fixed width,height", {
        x = .5,
        y = npl(),
        w = 400,
        h = 50
    })
    
    -- fontSize => width,height auto
    btns[#btns+1] = Btn("Fixed fontSize", {
        x = .5,
        y = npl(),
        fontSize = 64
    })
    
    -- width,height,fontSize => width,height max, favorite fontSize (if too large => adjusted)
    btns[#btns+1] = Btn("Fixed width,height,fontSize", {
        x = .5,
        y = npl(),
        w = 400,
        h = 80,
        fontSize = 24
    })
end

function draw()
    background(200)
    for _,v in pairs(btns) do v:draw() end
end
function touched(t)
    for _,v in pairs(btns) do v:touched(t) end
end
function orientationChanged(o)
    for _,v in pairs(btns) do v:orientationChanged(o) end
end

package.json

{
  "author":"HyroVitalyProtago",
  "id":"055093e0ec4f511e8fb6",
  "description":"Btn is a simple and lite button library for Codea",
  "version":"0.0.4",
  "codea":"2.3.1",
  "name":"Btn"
}