Code Android AddressBook interface

Need to write a function in Android Java as follows Input to the function: either Android Context/activity (if anything else is needed to run UI Thread inside the function, that can be passed as well) Processing : read Phone’s address book and dynamically shows first and last name in a scrollable list popup window (this pop up window has to be dynamically generated and will sit on top of whatever was there on the screen before) Output from the function: Once user selects a name return a JSON String containing all the details from address. Example of JSON {“firstName”:”John",”lastName”:”Doe”,”mobile”:"xxx-xxx-xxxx”,”work”:"xxx-xxx-xxxx”,”address":”some address”} The function will be called from an existing app and will be tested that way. The function must be callable from an Android activity.