Application demonstration in web browser applet

In general your application should run without any changes inside applet.

  • Keep it in mind that if your j2me application requires HTTP access to any site the applet and application jars must be signed. By default the applet will only communicate with the host the applet came from (your website). See MIDlet.getAppProperty.
  • Applet do not allow calls to System.getProperty() use "Save for Web..." or catch exceptions and handle them accordingly.
  • If you parctice code like this String.class.getResourceAsStream("stuff") this also would not work in Applet, use YourClass.class.getResourceAsStream("stuff") or "Save for Web...".

"Save for Web..."

"Save for Web..." function (in menu of main MicroEmulator application) does bytecode preprocessing of your application.

We are adding new class org.microemu.Injected to new JAR. Calls to System.getProperty(), System.out, System.err and getResourceAsStream are redirected to MicroEmulator Injected class.

The resulting JAR is safe to run on any other Emulator or device. Different Injected class with the same name is used when application is running under MicroEmulator.

Embedding applet into html page

MicroEmulator comes with three differend Skins:

  • Default 176x220 Full Screen and 176x176 Normal Canvas, Skin 226x471.
  • Minimum 128x128 Full Screen and 128x96 Normal Canvas, Skin 157x285. microemu-device-minimum.jar
  • Large 240x320 Full Screen and 240x266 Normal Canvas, Skin 292x618. microemu-device-large.jar

Html fragment example for Default device:

<applet code="org.microemu.applet.Main"
                width=226 height=471 archive="microemu-javase-applet.jar,(MIDlet application jar)">
        <param name="midlet" value="(MIDlet application main class)">
</applet>
  • To support Nokia UI microemu-nokiaui.jar should be included in the archive attribute.
  • To support Siemens API microemu-siemensapi.jar should be included in the archive attribute.

There is additional parameter in the applet definition tag if you want to start the applet with device other than the default one:

  <param name="device" value="(device main class or device.xml)">
  • Minimum phone included in distribution is org/microemu/device/minimum/device.xml
  • Minimum phone with mouse and color is org/microemu/device/minimum/device-color.xml
  • Large phone is org/microemu/device/large/device.xml

Remember to include the new device jar into the applet archive tag

  • minimum phone included in distribution is packaged inside microemu-device-minimum.jar
  • large phone included in distribution is packaged inside microemu-device-large.jar

Example for SimpleDemo MIDlet, Nokia UI support and Minimum device:

<applet code="org.microemu.applet.Main"
                width=157 height=285 archive="microemu-javase-applet.jar,microemu-nokiaui.jar,microemu-device-minimum.jar,microemu-demo.jar">
        <param name="midlet" value="org.microemu.midp.examples.simpledemo.SimpleDemoMIDlet">
        <param name="device" value="org/microemu/device/minimum/device.xml">
</applet>

Example for SimpleDemo MIDlet and Minimum device with mouse and color:

<applet code="org.microemu.applet.Main"
                width=157 height=285 archive="microemu-javase-applet.jar,microemu-device-minimum.jar,microemu-demo.jar">
        <param name="midlet" value="org.microemu.midp.examples.simpledemo.SimpleDemoMIDlet">
        <param name="device" value="org/microemu/device/minimum/device-color.xml">
</applet>

Example for SimpleDemo MIDlet and Large Skin:

<applet code="org.microemu.applet.Main"
                width=292 height=618 archive="microemu-javase-applet.jar,microemu-device-large.jar,microemu-demo.jar">
        <param name="midlet" value="org.microemu.midp.examples.simpledemo.SimpleDemoMIDlet">
        <param name="device" value="org/microemu/device/large/device.xml">
</applet>

MIDlet.getAppProperty

Function MIDlet.getAppProperty(String) is extended with additional properties so your MIDP application can be made aware of applet runtime environment.

  • "microemu.applet" the value would be "true" when application is running in applet
  • "microemu.accessible.host" the host name the applet is loaded from. This is the only host your application can communicate with while runing in applet.
  • Other named parameter from the applet HTML tag.

    Example:

    getAppProperty("demoServiceURL");

    <applet code="org.microemu.applet.Main"
                width=226 height=471 archive="microemu-javase-applet.jar,(MIDlet application jar)">
        <param name="midlet" value="(MIDlet application main class)">
        <param name="demoServiceURL" value="http://mycompany.com/appdemo/service.php">
</applet>