Ask the Guru

No super powers here …just BlackBerry technical expertise from Guru! Our technical expert is in the know and ready to answer your burning development questions. Consult the Guru. Selected questions and Guru’s replies will be featured in each newsletter, so stay tuned!


Clearly wants to know:
I would like to clear all stored information in Flash RAM in my BlackBerry device. Is there an easy way to do this?

Guru is crystal clear:
To clear the contents of the BlackBerry device, go through the Application Loader process and remove all data on the BlackBerry device. If that doesn’t float your boat, you can go through the Back-up/Restore process and remove each individual database present on the device.


News needy asks:
I've written an application that displays the headlines from a newspaper in a tree field structure. I would like to be able to experiment with a custom TreeField to incorporate colour in headlines to differentiate them and display headlines across multiple lines so that all of the text is visible.

Guru delivers front page news:
To change the TreeField appearance, you will have to override the default implementation of the TreeField. Please review the following Developer Knowledge Base articles outlining how to change a field’s text color and create a custom width for a ListField:


Disconnected inquires:
I wrote a HTTP client/server Java push application using BlackBerry MDS. It worked fine. Now I want to add communication between the client Java application and the server Java application, so that the client application lets the server application know if it is online or offline. How?

Guru makes the Connection:
The BlackBerry can make socket and http connections through your BlackBerry MDS Server to a server side application.  Have a look at the httpdemo or socketdemo samples included with BlackBerry JDE for code samples on how to make an http or socket connection on BlackBerry. 

Need information on the type of network connections that can be made on BlackBerry? Read it: What are the different ways to make an HTTP or socket connection?


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