After dissecting the demos that come with Ruboto 0.2 and figuring out how to upload a library and runner script to an Android emulator (hint: “$ adb push . /sdcard/jruby/subdirname”), it only took an hour or so to create a working Ruby On Acid demo. And what worked on the emulator immediately worked when uploaded to the phone.
$: << 'rubotoonacid/lib'
require 'rubyonacid/factories/example'
require "ruboto.rb"
java_import "android.graphics.Color"
java_import "android.graphics.Paint"
java_import "android.graphics.Canvas"
java_import "android.graphics.Bitmap"
java_import "android.content.res.ColorStateList"
java_import "org.jruby.ruboto.RubotoView"
f = RubyOnAcid::ExampleFactory.new
resetter = RubyOnAcid::SkipFactory.new(:odds => 0.99)
bitmap = Bitmap.create_bitmap(400, 854, Bitmap::Config::ARGB_8888)
buffer = Canvas.new(bitmap)
module Ruboto
java_import "org.jruby.ruboto.irb.R"
Id = JavaUtilities.get_proxy_class("org.jruby.ruboto.irb.R$id")
end
$activity.start_ruboto_activity "$arcs" do
setup_content do
RubotoView.new(self)
end
handle_draw do |view, canvas|
paint = Paint.new
paint.stroke_width = f.get(:width, :max => 10)
paint.color = Color.argb(
f.get(:alpha, :min => 50, :max => 255),
f.get(:red, :max => 255),
f.get(:green, :max => 255),
f.get(:blue, :max => 255)
)
paint.anti_alias = true
buffer.drawLine(
f.get(:x, :max => 400),
f.get(:y, :max => 854),
f.get(:x1, :max => 400),
f.get(:y1, :max => 854),
paint
)
canvas.draw_bitmap(bitmap, 0, 0, nil)
f.reset_assignments if resetter.boolean(:reset)
view.invalidate
end
handle_stop do
bitmap.recycle
end
endI do get a “bitmap size exceeds VM budget” error after the fourth run or so of the script, which persists until Ruboto is unloaded from memory. Calling Bitmap.recycle() in the handle_stop callback doesn’t seem to help. Gonna have to figure all that out before this is ready for prime time. Pretty damn sweet considering I once doubted I could ever use Ruby on the phone, though.
Update 2010-06-03: At Charlie Nutter’s request, I created an all-in-one script suitable for demoing. Point your phone here and open the link with Ruboto (0.2 or later), give it a moment to load, then choose Execute: acid.rb Startup is a bit slow; I’ll have to see if that can be improved for future scripts.
Update 2010-08-01: Here’s an updated version that uses touch input. Point your phone here and open the link with Ruboto (0.3.1 or later), give it a moment to load, then choose Execute: acid.rb.