Creating your first HTML-based AIR application with the AIR SDKFor a quick, hands-on illustration of how Adobe® AIR® works, use these instructions to create and package a simple HTML-based AIR “Hello World” application. To begin, you must have installed the runtime and set up the AIR SDK. You will use the AIR Debug Launcher (ADL) and the AIR Developer Tool (ADT) in this tutorial. ADL and ADT are command-line utility programs and can be found in the bin directory of the AIR SDK (see Installing the AIR SDK). This tutorial assumes that you are already familiar with running programs from the command line and know how to set up the necessary path environment variables for your operating system. Note: If you are an Adobe® Dreamweaver® user, read Create your first HTML-based AIR application with Dreamweaver.
Note: HTML-based AIR applications can only be developed for the
desktop and the extendedDesktop profiles. The mobile and tv profiles
are not supported.
Create the project filesEvery HTML-based AIR project must contain the following two files: an application descriptor file, which specifies the application metadata, and a top-level HTML page. In addition to these required files, this project includes a JavaScript code file, AIRAliases.js, that defines convenient alias variables for the AIR API classes.
Create the AIR application descriptor fileTo begin building your AIR application, create an XML application descriptor file with the following structure: <application xmlns="...">
<id>…</id>
<versionNumber>…</versionNumber>
<filename>…</filename>
<initialWindow>
<content>…</content>
<visible>…</visible>
<width>…</width>
<height>…</height>
</initialWindow>
</application>
This example only sets a few of the possible application properties. For the full set of application properties, which allow you to specify such things as window chrome, window size, transparency, default installation directory, associated file types, and application icons, see AIR application descriptor files. Create the application HTML pageYou now need to create a simple HTML page to serve as the main file for the AIR application.
Your HelloWorld.html file should now look like the following: <html>
<head>
<title>Hello World</title>
<script type="text/javascript" src="AIRAliases.js"></script>
<script type="text/javascript">
function appLoad(){
air.trace("Hello World");
}
</script>
</head>
<body onLoad="appLoad()">
<h1>Hello World</h1>
</body>
</html>
Test the applicationTo run and test the application from the command line, use the AIR Debug Launcher (ADL) utility. The ADL executable can be found in the bin directory of the AIR SDK. If you haven’t already set up the AIR SDK, see Installing the AIR SDK.
Create the AIR installation fileWhen your application runs successfully, you can use the ADT utility to package the application into an AIR installation file. An AIR installation file is an archive file that contains all the application files, which you can distribute to your users. You must install Adobe AIR before installing a packaged AIR file. To ensure application security, all AIR installation files must be digitally signed. For development purposes, you can generate a basic, self-signed certificate with ADT or another certificate generation tool. You can also buy a commercial code-signing certificate from a commercial certificate authority such as VeriSign or Thawte. When users install a self-signed AIR file, the publisher is displayed as “unknown” during the installation process. This is because a self-signed certificate only guarantees that the AIR file has not been changed since it was created. There is nothing to prevent someone from self-signing a masquerade AIR file and presenting it as your application. For publicly released AIR files, a verifiable, commercial certificate is strongly recommended. For an overview of AIR security issues, see AIR security (for ActionScript developers) or AIR security (for HTML developers). Generate a self-signed certificate and key pair From the
command prompt, enter the following command (the ADT executable
is located in the bin directory of the AIR SDK): adt –certificate -cn SelfSigned 1024-RSA sampleCert.pfx samplePassword ADT generates a keystore file named sampleCert.pfx containing a certificate and the related private key. This example uses the minimum number of attributes that can be set for a certificate. You can use any values for the parameters in italics. The key type must be either 1024-RSA or 2048-RSA (see Digitally signing an AIR file). Create the AIR installation file From the command prompt,
enter the following command (on a single line): adt -package -storetype pkcs12 -keystore sampleCert.pfx HelloWorld.air HelloWorld-app.xml HelloWorld.html AIRAliases.js You will be prompted for the keystore file password. The HelloWorld.air argument is the AIR file that ADT produces. HelloWorld-app.xml is the application descriptor file. The subsequent arguments are the files used by your application. This example only uses two files, but you can include any number of files and directories. ADT verifies that the main content file, HelloWorld.html is included in the package, but if you forget to include AIRAliases.js, then your application simply won’t work. After the AIR package is created, you can install and run the application by double-clicking the package file. You can also type the AIR filename as a command in a shell or command window. Next StepsIn AIR, HTML and JavaScript code generally behaves the same as it would in a typical web browser. (In fact, AIR uses the same WebKit rendering engine used by the Safari web browser.) However, there are some important differences that you must understand when you develop HTML applications in AIR. For more information on these differences, and other important topics, see Programming HTML and JavaScript. |
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