Launching Driving Directions with Lat and Long values from another activity
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Here's my situation:

 - I have a list that will launch different pages for different places.
 - Each of these pages already have a WebView and MapView showing the
   details and the map of the respective places (I used a TabHost)
 - I created an activity which extends ItemizedOverlay to enable me to place a marker, as well as to launch an alert dialog for my driving directions. This is used by all the MapView

I am able to launch driving directions from the alert dialog through the Google Maps app from my app so far. However, I have to put the lat and long values (actual numbers) in the Uri.parse("http://maps.google.com/maps..."). 

Is there a way to replace the lat and long values with strings from the Activity of the respective places?

P.S. Please pardon me as this is my first time posting here, and I am very new to programming =)