Question

I am new to Android, and I need some advices for start up.
I want to build an application, which will show up, when the user gets into some hot situation.

By hot situation I mean:

• the GPS/cell coordinates are in known zone;
• known Bluetooth device detected;
• known Wi-Fi network detected;
• weather info has change;

I see something running in background and when one of the clauses hit, it will trigger and open the app.

• How to get started?
• How do I make sure my app won’t be shut down?

As I read somewhere that Android OS will terminate apps if memory out occurs or consumes too much, and my app would consume a lot, making repeated measures/checks to see if situation changed.

Regards,
Pentium10

Answer 1

You need to use a Service for the part of your application that runs in the background.

You might find the Application Fundamentals document in the Android Developer Documentation helpful. It says this about Services:

A service doesn’t have a visual user interface, but rather runs in the background for an indefinite period of time. For example, a service might play background music as the user attends to other matters, or it might fetch data over the network or calculate something and provide the result to activities that need it.

In you case you might find the LocationManager Service helpful. It is a system Service which will you can use to notify your application based on GPS position.

However, I think you’ll have to write your own Services to monitor Wi-fi, Bluetooth and weather.

You can use the AlarmManager Service to get your Service to perform particular tasks at certain intervals.