Files
luaj/examples/android/assets/activity.lua
2014-01-27 17:50:34 +00:00

153 lines
4.0 KiB
Lua

-- Simple lua script that is executed when the activity start.
--
-- Arguments are the activity and the view.
local activity, view = ...
print('activity', activity, 'view', view)
-- forward declarations of local functions and variables
local animate,render
local chars = {}
local W, H = 600, 800
-- called on key down event
function onKeyDown(keyCode, event)
print('onKeyDown', keyCode, event)
end
-- called on key up event
function onKeyUp(keyCode, event)
print('onKeyUp', keyCode, event)
end
-- called on touch event
function onTouchEvent(event)
-- print('onTouchEvent', event)
local x1, y1 = event:getX(), event:getY()
local i,j = math.floor(x1*256/W), math.floor(y1*256/H)
local u = i + j * 256
local c = u < 0x80 and string.char(u) or
u < 0x800 and string.char(0xc0 + math.floor(u/0x80) % 0x20,
u % 0x80 ) or
string.char(0xe0 + math.floor(u/0x2000) % 0x8,
0x80 + math.floor(u/0x80) % 0x80,
u % 0x80)
while #chars > 4 do table.remove(chars, 1) end
table.insert(chars, {
n=255,
x=-4+12*math.random(),
y=-8+12*math.random(),
text=c})
return true
end
-- called on trackball event
function onTrackballEvent(event)
print('onTrackballEvent', event)
return true
end
function onWindowFocusChanged(hasWindowFocus)
print('onWindowFocusChanged', hasWindowFocus)
end
function onWindowSystemUiVisibilityChanged(visible)
print('onWindowSystemUiVisibilityChanged', visible)
end
-- called to draw the lua view
local prev, interval = os.time(), 1/60
local Thread = luajava.bindClass('java.lang.Thread')
function draw(canvas)
view:invalidate()
local curr = os.time()
local diff = curr - prev
if diff >= interval then
pcall(animate, canvas)
local wait = math.floor(1000 * (prev + interval - os.time()))
if wait > 0 then pcall(Thread.sleep, Thread, wait) end
prev = os.time()
end
pcall(render, canvas)
end
-- the animation step moves the line endpoints
local x1,y1,x2,y2,xi,yi = 160,240,480,240,0,0
local vx1,vy1,vx2,vy2,vxi,vyi = -5,-6,7,8,3,1
local w, h = W, H
local advance = function(x,vx,max,rnd)
x = x + vx
if x < 0 then
return 0, math.random(2,10)
elseif x > max then
return max, math.random(-10,-2)
end
return x, vx
end
animate = function(canvas)
x1,y1,x2,y2 = x1+1,y1+1,x2-1,y2-1
x1,vx1 = advance(x1,vx1,w)
y1,vy1 = advance(y1,vy1,h)
x2,vx2 = advance(x2,vx2,w)
y2,vy2 = advance(y2,vy2,h)
xi,vxi = advance(xi,vxi,w-100)
yi,vyi = advance(yi,vyi,h-100)
while #chars > 0 and chars[1].n <= 1 do
table.remove(chars, 1)
end
for i,c in pairs(chars) do
c.n = c.n - 1
end
end
-- classes that we need for rendering
local Color = luajava.bindClass('android.graphics.Color')
local Paint = luajava.bindClass('android.graphics.Paint')
local Style = luajava.bindClass('android.graphics.Paint$Style')
print('Color, Paint, Style', Color, Paint, Style)
-- colors that we use
local text_color, line_color = Paint.new(), Paint.new()
text_color:setColor(0xffffff33)
text_color:setTextSize(8.0)
line_color:setColor(0xffffaa33)
line_color:setStrokeWidth(1.5)
line_color:setStyle(Style.STROKE)
print('text_color, line_color', text_color, line_color)
-- load the logo image
local istream = view:findResource('logo.gif')
print('istream', istream)
local BitmapFactory = luajava.bindClass('android.graphics.BitmapFactory')
local logo = BitmapFactory:decodeStream(istream)
print('logo', logo)
-- the render step draws the scene
render = function(canvas)
-- scale the drawing to approximagely 600 x 800
W, H = canvas:getWidth(), canvas:getHeight();
local scale = (W + H) / (600 + 800)
canvas:scale(scale, scale)
w, h = W / scale, H / scale
-- redraw the canvas
canvas:drawColor(0xff112244)
-- line
canvas:drawLine(x1, y1, x2, y2, line_color)
-- text
canvas:translate(w/2,h/2)
for i,c in pairs(chars) do
local s = 200 / (256-c.n)
canvas:scale(s, s)
canvas:drawText(c.text, c.x-4, c.y+6, text_color)
canvas:scale(1/s, 1/s)
end
canvas:translate(-w/2,-h/2)
-- image
canvas:drawBitmap(logo,xi,yi)
end