Java Question Using JGrib java library

[hlo63]

Hi,

I am new at B4A and Java. I have done some development in VB and VBA.
I want to create an application that will, in a first time, read an display on a map weather forecast data extracted from Grib files (wind, pressure, rain,...).

A Java library (JGrib) has been developed to read and decode gribfiles. It is freely available in SourceForge.

I want to use this library within B4A. I have read all the posts regarding creating a B4A library using existing Java libraries. I have successfully created "MyFisrtLib" following the tutorial, but I am a still confused as to how I can expose Classes, Properties, Methods of the JGrib library.

I was looking for either :
- an example of the java code that has to be written in eclipse to do so but I did not find it in the forum,
- some help and may be the first lines of the java code that has to be written for this specific library.

Thanks in advance for your help.

Henri

 

[Erel]

You should reference this library in your eclipse project and add @DependsOn annotation to tell B4A compiler to also add a reference to this jar.

You can then create methods in the wrapper that access the other library.

 

[hlo63]

Erel,

Thank you for your reply.
I already had the @DependsOn annotation in my eclipse project.

The thing is that I do not know how to "create methods in the wrapper that access the other library". An example would be very helpful. For example, in the JGrib Library, one of the main class is "GribFile". How do I expose it and how do I expose one of its method like for example "getRecord"?

Henri

 

[Erel]

There are several possible solutions.
The simplest one is to create GribFileWrapper class with the @ShortName GribFile. The wrapper class just calls the methods of the "real" class.