Introduction to Sencha Cmd

Sencha Cmd is a cross-platform command line tool that provides many automated tasks around the full life-cycle of your applications, from generating a new project to deploying an application to production.

Sencha Cmd provides a collection of powerful, time-saving features that are designed to work together and in conjunction with the Sencha Ext JS and Sencha Touch frameworks. Sencha Cmd provides the following capabilities:

• Code generation tools to generate entire applications and extend those applications with new MVC components.
• A framework-aware, JavaScript compiler that knows the semantics of Sencha frameworks and can produce minimal footprint builds from your source. In the future, the compiler will optimize many of the high-level semantics provided by Sencha frameworks to reduce load time of your applications.
• Native packaging to convert your Sencha Touch application into a first-class, mobile application that has access to device functionality and can be distributed in App Stores.
• Powerful code selection tools for tuning what is included in your application's final build, determine common code across pages and partition shared code into "packages" - all using high-level set operations to get builds exactly as you want them.
• Workspace management to assist in sharing code between pages or applications.
• Image extraction to convert CSS3 features (such as border-radius and linear-gradient) into sprites for legacy browsers.
• Flexible configuration system that enables defaults to be specified for command options at the application or workspace level or across all workspaces on a machine.
• Robust logging to help you understand the inner workings of commands and facilitate troubleshooting.
• Integration with Apache Ant.
• Code generation hooks that can be specific to one page or shared by all pages in the workspace, for example, to check coding conventions or guidelines as new models are generated).

Compatibility

Sencha Cmd is designed for Sencha Ext JS version 4.1.1a or higher and Sencha Touch version 2.1 or higher. Many of the new features of Sencha Cmd require framework support that is only available at these version levels. There are some low-level commands that can be used for older versions of Sencha frameworks or JavaScript in general.

If you are using an older version of Ext JS, you may use Sencha Cmd's build command to build via your JSB file. In other words, Sencha Cmd can replace JSBuilder to produce a compressed build of the files described in a JSB file. Sencha Cmd will not update your JSB file as was done by the previous SDK Tools v2. If your build process requires this support, then you should wait to upgrade to Sencha Cmd.

Sencha Touch 2.0.x requires SDK Tools v2.

System Setup

Follow these steps to set up your system and start using Sencha Cmd:

1. Download and install a Java Run-time Environment or JRE. It is best to download the most up-to-date version available. The JRE version must be at least JRE 6.
2. Download and install Compass. Compass may have its own system requirements. Compass is required for several features of Sencha Cmd.
3. Download and install Sencha Cmd.
4. Download the appropriate version of the Ext JS SDK or Sencha Touch SDK.
5. Extract the SDK to a local directory.

Next, you need to verify that Sencha Cmd is working properly on your machine. Open a command line terminal, and run the following commands. Replace /path/to/sdk with the actual path to the SDK that you extracted to previously (not the Sencha Cmd directory).

cd /path/to/sdk
sencha

You should see output that starts like this:

Sencha Cmd v3.0.0
...

If the above message appears and the version number is 3.0.0 or higher you are all set.

Command Basics

All of the features provided by Sencha Cmd are arranged in categories (or modules) and commands.

sencha [category] [command] [options...] [arguments...]

Help is available using the help command.

sencha help [module] [action]

For example, try this:

sencha help

And you should see this:

Sencha Cmd v3.0.0

OPTIONS
  * --debug, -d - Sets log level to higher verbosity
  * --plain, -p - enables plain logging output (no highlighting)
  * --quiet, -q - Sets log level to warnings and errors only
  * --sdk-path, -s - sets the path to the target sdk

CATEGORIES
  * compile - Compile sources to produce concatenated output and metadata
  * generate - Generate code like models and controllers or raw templates
  * theme - Builds a set of theme images from a given html page
  * app - Perform various application build processes

COMMANDS
  * ant - Invoke Ant with helpful properties back to Sencha Cmd
  * build - Builds a project from a JSB3 file.
  * config - Loads a config file or sets a configuration property
  * help - Get help on using Sencha Cmd

Current Directory

In many cases, Sencha Cmd requires you to set a specific current directory. Or it may just need to know details about the relevant SDK. This can be determined when Sencha Cmd is run from a generated application folder or, for some few commands, from an extracted SDK folder.

Important. For the following commands, Sencha Cmd needs to be run from the root folder of a generated application. They will fail if not run from such a folder.

* `sencha generate ...` (all commands other than `app` and `workspace`)
* `sencha app ...`

To generate an application you can run the following command from an extracted SDK folder:

cd /path/to/SDK
sencha generate app ...

Or you can use the -sdk switch like so:

sencha -sdk /path/to/sdk generate app ...

When using the compiler, Sencha Cmd detects the framework in use when run from an application folder. If you are not running from a generated application, you may need to use the -sdk switch:

sencha -sdk /path/to/sdk compile ...

Developing Applications

The starting point for most projects is to generate an application skeleton. This is done using the following:

sencha -sdk /path/to/sdk generate app MyApp /path/to/MyApp

Ext JS and Sencha Touch applications are structured differently from each other. Further, particularly with Ext JS, applications can be quite large and may contain multiple pages.

To get started building applications using Sencha Cmd, consult the Using Sencha Cmd guide.

Beyond The Basics

There are many other details related to using Sencha Cmd that can be helpful. The help command is a great reference, but if you want to walk through all the highlights, consult Advanced Sencha Cmd.

Troubleshooting

Here are some tips for solving common problems encountered when using Sencha Cmd.

Command Not Found

If running sencha results in the error message sencha: command not found on OSX/Linux or 'sencha' is not recognized as an internal or external command, operable program or batch file on Windows, follow these steps:

• Close all existing terminal/command prompt windows and reopen them.
• Make sure that Sencha Cmd is properly installed:
  • The installation directory exists. By default, the installation path is:
    • Windows: C:\Users\Me\bin\Sencha\Cmd\{version}
    • Mac OS X: ~/bin/Sencha/Cmd/{version}
    • Linux: ~/bin/Sencha/Cmd/{version}
  • The path to Sencha Cmd directory is prepended to your PATH environment variable. From the terminal, run echo %PATH% on Windows or echo $PATH on Mac or Linux. The Sencha Cmd 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_CMD_{version} is set, with the value being the absolute path to the installation directory mentioned above. For example, if the installed version is 3.0.0, a SENCHA_CMD_3_0_0 must be set. If the output is empty, set the environment variable manually. To check, go to the command prompt (or Terminal) and run:
    • Windows: echo %SENCHA_CMD_3_0_0%
    • Other - echo $SENCHA_CMD_3_0_0

Compass is not a recognized command

If you see an error related to not recognizing or finding "compass" this is likely because Compass is not installed or is not in your PATH. See the System Requirements above.

Wrong Current Directory

A common mistake is to perform a command that requires the current directory to be either an extracted SDK directory or an application directory, but such a directory has not been set. If this requirement is not met, Sencha Cmd displays an error and exits.

Note that a valid application directory is one that was generated by Sencha Cmd.

Errors While Resolving Dependencies

The sencha app build command works by reading your index.html and scanning for required classes. If your application does not properly declare the classes it requires, the build usually completes but will not contain all the classes needed by your application.

To ensure that you have all required classes specified, always develop with the debugger console enabled ("Developer Tools" in IE/Chrome, FireBug in FireFox and Web Inspector in Safari) and resolve all warnings and error messages as they appear.

Whenever you see a warning like this:

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

Immediately add 'Ext.foo.Bar' 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.