Touch 2.0.2 Sencha Docs

Using Sencha Command

Sencha Command is a cross-platform command line tool that helps make developing applications with Sencha SDKs full of enjoyment. The tool consists of many useful automated tasks around the full life-cycle of your applications, from generating a fresh new project to deploying for production.


Please note the content of this guide currently applies only to Sencha Touch 2.

Step 1: Setup an HTTP server on your computer if you don't have one running. This guide assumes that the host name is localhost, and the document root is at /path/to/www

Step 2: Download and install the latest SDK Tools on your development machine. The latest version as of this writing is 2.0.0-beta2.

Step 3: Download the latest Sencha Touch 2 SDK. Extract the SDK to a local directory. The latest version as of this writing is 2.0.1-rc.

Step 4: Verify that Sencha Command is working properly on your machine:

Open a command line terminal, and run the following commands. Replace /path/to/sencha-touch-2-sdk with the actual path to the SDK that you extracted to previously (not the SDK Tools directory), as mentioned in Step 2.

cd /path/to/sencha-touch-2-sdk

If a help message appears with the first line that says: "Sencha Command v2.0.1", you are all set.

Getting Started

All commands have the exact same syntax as follows:

sencha [module] [action] [arguments...]

Some typical examples:

# Minify app.js and write the output to app.minified.js
sencha fs minify app.js app.minified.js

# Create a new project based on the current SDK with namespace 'MyApp' and store inside '/path/to/www/myapp'
sencha app create MyApp /path/to/www/myapp

To see a list of all available modules, simply type: sencha (when the current working directory is either the SDK directory or a project directory)

Similarly, to see a list of all available actions for a specific module, run: sencha [module], for example: sencha app

Lastly, typing sencha [module] [action] prints out the full list of arguments for that typical action, for example: sencha app create

Creating a New Application

The following command generates a new application with the namespace MyApp to /path/to/www/myapp:

#  Make sure the current working directory is the Sencha Touch 2 SDK
cd /path/to/sencha-touch-2-sdk
sencha app create MyApp /path/to/www/myapp

To try it out, simply point your (WebKit-based) browser to http://localhost/myapp.

Congratulations, you have just created a fully working Sencha Touch 2 application in seconds!

Understanding Your Application's Structure

The generated application should have the following file structure:

app                     # Your application's source code in MVC structure
        Main.js         # The main view of the application

        app.css         # The main stylesheet, compiled from app.scss

        app.scss        # The SASS file which compiles to app.css above,
                        # includes Sencha Touch 2 theme by default

    icons               # Application icons for all mobile devices
                        # When replacing these default images with your own,
                        # make sure the file name and the dimension stays exactly the same
    loading             # Application start-up screens for iOS devices
                        # Similarly to icons, make sure the file names and
                        # dimension stays the same
    images              # Put other images used by your application here

sdk                     # A copy of the SDK from which this application was generated

app.js                  # Contains application's initialization logics
app.json                # Configuration for deployment
packager.json           # Configuration for native packaging

Both app.json and packager.json have inline documentation for each configurable item. Simply open the files and edit them as you need.

Developing Your Application

sencha generate helps you quickly generate common MVC components such as: Controller, Model and Profile.

For example:

#  Make sure the current working directory is the application's directory, i.e 'cd /path/to/www/myapp'
sencha generate model User --fields=id:int,name,email

The command above will automatically generate a new Model class named User with 3 fields of id, name and email to app/model/User.js, and add its reference to your app.js.

Upgrading Your Application

Generated applications always have their own copies of the SDK from which they were originally generated. Upgrading your application to the a new of the SDK means replacing the old copy with the new one.

Starting from SDK Tools v2.0.0-beta2 and Sencha Touch SDK v2.0.1-rc, you can seamlessly upgrade your application to the new downloaded SDK using sencha app upgrade. Firstly do make sure your current working directory is the new SDK directory:

cd /path/to/new_version_of_sdk

then run:

sencha app upgrade /path/to/your_application

Deploying Your Application

Developing your application simply means editing source code and refreshing the browser. All source files are dynamically loaded on demand. There's no building process involved.

When it comes to deployment, Sencha Command provides 4 different build environment options, namely 'testing', 'package', 'production' and 'native':

  • 'testing' is meant for QA prior to production. All JavaScript and CSS source Files are bundled, but not minified, which makes it easier for debugging if needed
  • 'package' creates a self-contained, re-distributable production build that normally runs from local file system without the need for a web server
  • 'production' creates a production build that is normally hosted on a web server and serves multiple clients (devices). The build is offline-capable using HTML 5 application cache, and has built-in over-the-air delta updating feature
  • 'native' first generates a 'package' build, then packages it as a native application, ready to be deployed to native platforms

As an example, the following command generates a 'testing' build for your application:

#  Make sure the current working directory is the application's directory you're deploying, i.e 'cd /path/to/www/myapp'
sencha app build testing

And similarly when you're ready for production deployment:

sencha app build production

The default deployment paths are taken from the buildPaths item inside app.json. For more details on optional arguments, run

sencha app build

Sencha Command automates all optimizations for your application, including but not limited to:

  • Resolving dependencies required by the application and only including exactly what is used for optimal file size / performance
  • Enabling HTML 5 application cache via automatic generation of cache.manifest and resources checksum
  • Minifying all JavaScript and CSS assets
  • Storing all JavaScript and CSS assets inside Local Storage on first load, and patches them via delta updates between releases

As a result, your production build can load instantly on subsequent access and updates on-the-fly with minimal network transfer.

Important Note: The cache.manifest file is automatically generated for you. However, please make sure that your web server serves it with the correct Content-Type header of text/cache-manifest. To learn more about HTML 5 application cache, please refer to this article.

Packaging Your Application for Distribution on App Stores

packager.json contains all configurable values to package your application.

If you are using OS X and have Xcode installed, this one-liner will automatically package your application and run it on iOS Simulator:

sencha app build native

For more details on working with packager.json, please refer to the Native Package guide


Command Not Found

Upon running sencha, if there is an error message appears saying "sencha: command not found" on OS X / Linux or "'sencha' is not recognized as an internal or external command, operable program or batch file." on Windows, follow these steps to troubleshoot:

  • Close all existing terminal / command prompt windows and re-open them.
  • Make sure that Sencha SDK Tools is properly installed:
    • The installation directory exists. By default, the installation path is /Applications/SenchaSDKTools-{version} on OS X, /opt/SenchaSDKTools-{version} on Linux, and C:\Program Files\SenchaSDKTools-{version}
    • The path to SDK Tools directory is prepended to your system's PATH environment variable. From the terminal, run echo $PATH (echo %PATH% on Windows). The SDK Tools directory should be displayed in part of the output. If this is not the case, add it to your PATH manually.
    • The environment variable SENCHA_SDK_TOOLS_{version} is set, with the value being the absolute path to the installation directory mentioned above. For example: If the installed version is '2.0.0-beta2', a SENCHA_SDK_TOOLS_2_0_0_BETA2 must be set. From the terminal, run echo $SENCHA_SDK_TOOLS_2_0_0_BETA2 (echo %SENCHA_SDK_TOOLS_2_0_0_BETA2% on Windows). If the output is empty, set the environment variable manually.

Wrong Current Directory

A common mistake is not running sencha command within either a valid SDK directory or an application directory. If the current directory is not a SDK or application directory, sencha command will fallback to backwards-compatible mode. As of SDK Tools release '2.0.0-beta2', you should see a clear warning in such case:

The current working directory (...) is not a recognized Sencha SDK or application folder. Running in backwards compatible mode.

Note that a valid application directory is one that was generated by Sencha Command, or one that properly follows the structure described above.

Errors While Resolving Dependencies

When deploying the application using sencha app build command, by default your application is launched via file system protocol inside a headless WebView to extract its dependencies. In other words, your application needs to load without errors for the build process to work properly.

Always develop with the debugger console enabled (Web Inspector for Safari / Developer Tools for Chrome) and resolve all warnings / error messages as they appear. Whenever you see a warning like this:

[Ext.Loader] Synchronously loading ''; consider adding '' explicitly as a require of the corresponding class

Immediately add '' inside the requires array property of the class from which the dependency originates. If it is a application-wide dependency, add it to the requires array property inside Ext.application(...) statement.

If your application relies on any dynamic server-side scripting, for example: loading class configuration from a PHP script, you must set the 'url' item inside 'app.json' to the absolute URL from which your application can be loaded on a web browser. For example:

// app.json
    "url": "http://localhost/myapp/",
    // ...