Alloy howtos

alloy-howtos

Overview

Practical reference for Titanium Alloy MVC projects: CLI usage, project configuration, conditional rendering, custom XML tags, cross-controller communication, and common compilation/runtime errors. Reference-style — load the relevant file from references/ for deeper detail.

When to use

Use this skill when:

• The project contains app/views/ + app/controllers/, alloy.jmk, or config.json
• Running or scripting the Alloy CLI (alloy new, alloy generate, alloy compile, ...)
• Configuring alloy.jmk build hooks or config.json environment / platform precedence
• Writing conditional views with if= in XML or TSS
• Building reusable custom XML tags in app/lib/
• Wiring cross-controller communication via Backbone.Events
• Diagnosing Alloy compilation errors or platform-specific runtime issues

Do NOT use for:

• Alloy MVC concepts, controllers, models, or data binding (use alloy-guides)
• Titanium SDK fundamentals, tiapp.xml, Hyperloop, or app distribution (use ti-guides)
• Native module dependency updates (use ti-module-update)

Quick reference

Topic	Reference
Coding standards, naming, global events patterns	best_practices.md
All CLI commands with options and model schema format	cli_reference.md
alloy.jmk tasks, config.json structure, widget.json format	config_files.md
Creating reusable custom XML tags without widgets	custom_tags.md
Common errors with solutions	debugging_troubleshooting.md
Controller examples, conditional views, data-binding patterns	samples.md

Key practices

Naming conventions

• Never use double underscore prefixes (__foo) — reserved for Alloy
• Never use JavaScript reserved words as IDs

Global events — use Backbone.Events

Avoid Ti.App.fireEvent / Ti.App.addEventListener. They cross the native-JS bridge and can cause memory leaks and slower execution.

Use the Backbone.Events pattern:

// In alloy.js
Alloy.Events = _.clone(Backbone.Events);

// Listener
Alloy.Events.on('updateMainUI', refreshData);

// Clean up on close
$.controller.addEventListener('close', () => {
    Alloy.Events.off('updateMainUI');
});

// Trigger
Alloy.Events.trigger('updateMainUI');

Global variables in non-controller files

Always require Alloy modules:

const Alloy = require('alloy');
const Backbone = require('alloy/backbone');
const _ = require('alloy/underscore')._;

Conditional views

Use if attributes in XML for conditional rendering (evaluated before render):

<Alloy>
    <Window>
        <View if="Alloy.Globals.isLoggedIn()" id="loggedIn">
            <Label text="Logged in" />
        </View>
        <View if="!Alloy.Globals.isLoggedIn()" id="notLoggedIn">
            <Label text="Not logged in" />
        </View>
    </Window>
</Alloy>

Conditional TSS styles:

"#info[if=Alloy.Globals.isIos7Plus]": {
    font: { textStyle: Ti.UI.TEXT_STYLE_FOOTNOTE }
}

Data-binding conditionals:

<TableViewRow if="$model.shouldShowCommentRow()">

Common error solutions

Error	Solution
No app.js found	Run alloy compile --config platform=<platform>
Android assets not showing	Use absolute paths (prepend /)
Alloy is not defined (non-controller)	Add const Alloy = require('alloy');
iOS invalid method passed to UIModule	Creating Android-only object — use platform attribute

CLI quick reference

# New project
alloy new [path] [template]

# Generate components
alloy generate controller <name>
alloy generate model <name> <adapter> <schema>
alloy generate style --all

# Compile
alloy compile [--config platform=android,deploytype=test]

# Extract i18n strings
alloy extract-i18n en --apply

# Copy / move / remove controllers
alloy copy <old> <new>
alloy move <old> <new>
alloy remove <name>

Configuration files priority

config.json precedence: os:<platform> > env:<environment> > global

Access at runtime: Alloy.CFG.<key>

Custom XML tags

Reusable components without the overhead of widgets. Drop a file in app/lib/:

app/lib/checkbox.js

exports.createCheckBox = args => {
    const wrapper = Ti.UI.createView({ layout: 'horizontal', checked: false });
    const box = Ti.UI.createView({ width: 15, height: 15, borderWidth: 1 });
    // ... build component, return Ti.UI.* object
    return wrapper;
};

view.xml

<CheckBox module="checkbox" id="terms" caption="I agree" onChange="onCheck" />

The module attribute points to the file in app/lib/ (without .js). The function must be create<TagName>.

See custom_tags.md for the complete worked example.

Related skills

Task	Use this skill
Alloy MVC concepts, controllers, models, data binding	alloy-guides
Titanium SDK config, Hyperloop, app distribution	ti-guides
Titanium API lookup (Ti.UI, Ti.Network, modules)	ti-api
Native module dependency updates	ti-module-update