In both
Series 40 and Symbian (Java Runtime 2.1 for Symbian onwards), MIDlets
can be launched with platformRequest using the localapp: scheme. For example:
platformRequest("localapp://jam/launch?midlet-name=ArcadeGames;midlet-vendor=Acme;sounds=OFF;difficulty=easy;wizard_mode=ON"); The MIDlet to be launched is identified by the combination of
the MIDlet suite name (midlet-name), vendor (midlet-vendor). In case the suite has multiple MIDlets,
the MIDlet needs to be identified with MIDlet number (midlet-n).
The midlet-name, midlet-vendor and midlet-n attribute values are case sensitive.
They must match their corresponding attribute values of MIDlet-Name, MIDlet-Vendor and <n> in MIDlet-<n>.
In
Symbian, the application declares the parameters it supports using
the Nokia-MIDlet-Launch-Params JAD/JAR manifest
attribute . The application can access the parameters through
system properties. Parameters not listed in Nokia-MIDlet-Launch-Params are not passed to the application. For example, the MIDlet Acme/ArcadeGames needs to define the following attribute
(Symbian only):
Nokia-MIDlet-Launch-Params: sounds,difficulty,wizard_mode
The ArcadeGames MIDlet can access the parameters as follows:
System.getProperty("sounds");
System.getProperty("difficulty");
System.getProperty("wizard_mode");
From Java Runtime 2.1 for Symbian onwards, also the javaapp: scheme can be used for launching MIDlets.
platformRequest("javaapp:midlet-name=ArcadeGames;midlet-vendor=Acme;sounds=OFF;difficulty=easy;wizard_mode=ON");
In Symbian, when a MIDlet starts, it can acquire the
full command line from system property com.nokia.mid.cmdline.
In Symbian , a MIDlet can also be launched using the MIDlet's UID. The MIDlet UID can be in hexadecimal or decimal format. For example:
platformRequest("javaapp:midlet-uid=0xE1000000;sounds=OFF;difficulty=easy;wizard_mode=ON);
A Manufacturer/Operator signed MIDlet can use the platformRequest method
(which is specified in MIDP2 specification) to invoke other MIDlets
installed on the phone via the localapp URI
scheme. After a successful MIDlet launch and exit of the target MIDlet,
the user can be returned to the MIDlet that initiated this invocation
by specifying the additional parameter chaining=true in the platformRequest URI.
This behavior is called 'MIDlet chaining' where MIDlet A invokes MIDlet B, and the user is taken back to MIDlet A after the exit of MIDlet B.
For
example localapp://jam/launch?midlet-name=NokGolf;midlet-vendor=Nokia;midlet-version=1.2;chaining=true
Dependencies and platform restrictions:
By default 'MIDlet chaining' is disabled. Not specifying this
parameter in the URI is equivalent to chaining=false.
In order to use the feature, the device needs to support JSR 211 Content Handler API.
This feature is restricted to MIDlets belonging to Manufacturer and Operator domain.
In case of a MIDlet suite with multiple MIDlets, this method
will always invoke the MIDlet specified by the MIDlet-1 attribute in the JAD file; that is, the first MIDlet
in the suite.
In Symbian the parameter is ignored. As multitasking is supported, 'MIDlet chaining' is in a sense always enabled.
An example snippet of code specifying the method use follows:
public class xyzMIDlet extends MIDlet{
//.....................
//......................
String url = "localapp://jam/launch?midlet-name=NokGolf;midlet-vendor=Nokia;chaining=true";
if (platformRequest(url)){
System.out.println("midlet exit required");
notifyDestroyed();
}
else
{
System.out.println("midlet exit NOT required");
}
//.....................
//......................
} // end of MIDlet class