Want a Android bluetooth to be always visible until app running?

Question

I want that my bluetooth to be visible until the app is running. Like for infinite time. I will turn it off when Im done with it.

I don\'t want it to ask user for du

Answer 1

The short answer is that you can't; see this bug report. Trust me, I'm as annoyed about this as you are; it makes ad-hoc networking on Bluetooth very difficult. There are some suggestions on that thread that the limitation is gone in Honeycomb and perhaps will make it into Ice Cream Sandwich. For the moment, there is no way around it, short of installing a custom ROM.

With that said, there are some workarounds. Since Android requires pairing before any Bluetooth socket (server or client) can send data, your app can simply try and connect to already paired devices. Sure, most of the time the connection will fail, but if a paired device is in range the connection will happen. I've implemented this in an application of mine and it seems to work. I'm not sure how this affects battery life, but with enough time between scans you ought to be okay.

I'm hoping that future versions of Android won't have this unnecessary limitation as it prevents some potentially interesting ad-hoc networking applications.

Answer 2

I am confused, because on Android Dev Guide, it is said the following:

[..] By default, the device will become discoverable for 120 seconds. You can define a different duration by adding the EXTRA_DISCOVERABLE_DURATION Intent extra. The maximum duration an app can set is 3600 seconds, and a value of 0 means the device is always discoverable. Any value below 0 or above 3600 is automatically set to 120 secs). For example, this snippet sets the duration to 300.[..]

Isnt it the feature we are looking for?

Answer 3

There's a reason that you can't set the bluetooth to be always on - the battery would drain really fast. I suggest you think of another way around your issue.