Alloy

Alloy splits a screen into three files: an XML view for structure, a TSS file for style, and a JavaScript controller for behaviour. It compiles all three into ordinary Titanium code before the build, so it is a layer over the API rather than a different runtime, and anything you can do in Classic you can do here.

It is a separate install:

npm i -g alloy

alloy new converts an existing Classic project in place, which is why choosing Classic first costs nothing. See your first app for that choice.

What it gives you

Separation. A 400-line file that builds a screen becomes an XML file you can read at a glance and a controller with only the behaviour in it.

Styling by selector. TSS applies properties by element type, class or id, across the whole app or one screen, so a button style is written once.

Compile-time platform code. OS_IOS and OS_ANDROID are constants replaced during compilation, so the branch not taken is removed from the build rather than evaluated on the device.

Data binding. A Backbone collection can drive a ListView directly, so adding a row is a model operation rather than a view operation.

The pages

Views is the XML: elements, ids, classes, and how an element becomes a Ti.UI.create* call.

Styles and themes is TSS: selectors, precedence, platform and form-factor queries, and themes.

Controllers is the JavaScript: the $ namespace, arguments, opening and closing, and cleaning up.

Models and collections is the data layer, its sync adapters, and binding a collection to a list.

Widgets is how to package a piece of UI for reuse across projects.

Configuration is config.json, Alloy.CFG, and the compile-time constants.

Where the files go

app/
  views/        index.xml
  styles/       app.tss, index.tss
  controllers/  index.js
  models/
  widgets/
  lib/          plain modules, required by path
  assets/       images, and semantic.colors.json
  themes/
  alloy.js      runs before the first controller
  config.json

Resources/ is Alloy's output and is regenerated on every build. Do not edit it, and do not commit it. See project structure.