Code 03 - Button Extended

-- Code 03 - Button Extended
-- Can be uploaded to Codea
-- uses code by David Such
-- Bruce Elliott
-- April 2013

-- Button returns its label when pressed

--# Button
Button = class()

function Button:init(displayName)
-- you can accept and set
-- parameters here

    self.displayName = displayName
    self.pos = vec2(0,0)
    self.size = vec2(0,0)
    self.action = nil
    self.color = color(68, 65, 190, 255)
end

function Button:draw()
-- Codea does not automatically
-- Determine button size based on displayName
-- Draw the button (uses rect)
-- Use text to draw text on button

    pushStyle()
    fill(self.color)
    font("ArialRoundedMTBold")
    fontSize(22)

    local w, h = textSize(self.displayName)
    w = w + 20
    h = h + 20

    rect(self.pos.x - w/2,
         self.pos.y - h/2,
         w, h)
    self.size = vec2(w, h)

    textMode(CENTER)
    fill(54,65,96,255)
    text(self.displayName,
	self.pos.x, self.pos.y)

    popStyle()
end

function Button:hit(p)
-- Accepts p - x and y of the touch
-- Button knows its position
-- If touch is inside button return true
-- otherwise return false

    local l = self.pos.x - self.pos.x/2
    local r = self.pos.x + self.pos.x/2
    local t = self.pos.y + self.pos.y/2
    local b = self.pos.y - self.pos.y/2

    if p.x > l and p.x < r
      and p.y > b and p.y < t then

      return true
    end

    return false
end

function Button:touched(touch)
-- if touch has ended and the touch was on the button
-- set newName and call action

    if touch.state == ENDED and
       self:hit(vec2(touch.x, touch.y)) then
        if self.action then
            newName = self.displayName
           self.action()
        end
    end
end

function Button:action()
-- call buttonPressed in main to display newName

    buttonPressed(newName)
end

--# Main
-- ButtonDemo

-- Use this function to perform
-- our initial setup
function setup()
-- Create button with a name

    print("Button  Test Project")
    button = Button("Test")
end

-- This function gets called once every frame
function draw()
-- calls drawButton to put button on screen

    -- This sets a dark background color
    background(0)

    -- This sets the line thickness
    --  strokeWidth(5)

    -- Do your drawing here
   drawButton()
end

function drawButton()
-- set button position
-- call button draw

     button.pos = vec2(400, HEIGHT/2)
    button:draw()
end

function touched(touch)
-- if touched call button:touched
    button:touched(touch)
end

function buttonPressed(keyName)
-- display button name if it was pressed

    print("Button: "..keyName)
end