Develop Reference

Can I have a listener for the physical hardware button that is present on the side of the Android watch?

My android watch has a single hardware (physical) button on the side. Is it possible to program a listener for this button, so that it can be used as an additional control in my program?

I don't believe this is possible. The usual way to detect a standard button press (like Back) in Android is with an onKeyDown listener, and this doesn't fire in an Activity on Wear when the stem button is pressed (tested on both Wear 1.5 and the 2.0 dev preview).
It's always iffy to assert something is categorically not possible, because there's always the chance that someone will find a clever hack to make it happen. And I wouldn't mind being proved wrong. But until such a hack comes along, I'm going to say no, it's not.

Android: enumerating the buttons on a gamepad

I have an Android device into which a gamepad can be connected (it's a totally standard XBox 360 controller, but I need to support other varieties as well). The gamepad is showing up as a InputDevice with some analogue axes and some buttons.
I need to be able to query Android to find out what buttons the gamepad supports. Does anyone know how to do this?
I know that the system has this information, because if I write a command-line app which opens /dev/input/event... and queries the buttons using the EVIOCGBIT ioctl, I get a nice list of supported buttons from the kernel. But I can't do this from an Android application because I don't have permission to access the input devices directly.
It looks like it should be possible to get the InputDevice's KeyCharacterMap object and query that; but it looks like Android has attached the default QWERTY keyboard keymap to the gamepad, rather than constructing one that actually matches what the gamepad supports. This will happily tell me that the gamepad has a Q key, which it doesn't, and that it doesn't have a BUTTON_X key, which it does, and for which I am receiving key events. So that's not helping.
Is there any way to do this?

I haven't figured out a way yet, but I have found a horrible workaround.
If you call KeyCharacterMap.deviceHasKey(keycode), I can ask Android if any input device on the system supports the specified keycode. By iterating through all possible buttons that can occur on a gamepad (usefully, they're all called KeyEvent.KEYCODE_BUTTON_something), I can figure out that any connected gamepad must support at least some of these buttons.
It's not a very nice solution --- if I have an XBox 360 controller and a Wiimote connected at the same time, then I can't figure out that the XBox controller does not have buttons 1 or 2, and the Wiimote does not have X or Y, for example. But at least it's a start.
If anyone has any better ideas, please suggest some...

Reacting to multi-buttons wired headphones

I am driving some experiments with a pair of a-JAYS Four headphones (having 3 buttons on its wired remote/mic) plugged onto a Galaxy Nexus (ICS 4.0.2).
My issue is that only the middle button is 'recognised' by a test app I have written, i.e. triggering both Intent.ACTION_MEDIA_BUTTON and/or Activity.onKeyDown callback with KeyCode 79 when it is pressed.
Pressing the two other buttons don't trigger any of the previous methods. For info, those headphones and its 3 buttons work on Apple iPhones and Apple computers (at least a MacBookPro 2011), as advertised on the box...
Firstly I thought Android or my device could simply not handle more than one button on a wired jack remote (even if that sounds weird...) but then I had a try with a pair of headphones from HTC (the ones coming with one of their Desire device) having 3 buttons. Middle button would react the same way as my a-JAYS, but the two other buttons are also recognised with KeyCodes 87 and 88, respectively Play Previous and Play Next media keys.
So it seems that either the device or the low levels layers of Android are simply not able to catch certain headphones buttons signals :/ (at least those which are not 87 and 88)
Any idea anyone about how to make Android able to recognise other buttons/signals from such headphones as Apple compatible ones? Would it imply low levels drivers writing for ICS or am I missing something really obvious?
Any help would be much appreciated. Can post my test-app code if needed.
Cheers

The signals/ resistance from the volume control buttons (1.525-1.495 V for volume down, and 1.619-1.587 V for volume up) are currently unable to be recognized through the android framework's software. I believe this has to do with Apple having a patent on the designated volume controls and so Google won't release to developers how the framework recognizes particular signals through the fourth connector on the headphone jack. The center/mic/action buttons on headsets generally work, it shorts the path from ~2V to ~0V and Apple does not own the patent for that. If someone could figure out how to interact with the inputs on their own that would be huge. I am tempted to learn app development and find a workaround.

The problem is more complicated that it seems: http://david.carne.ca/shuffle_hax/shuffle_remote.html .

I have to emphasize that I am no expert on this topic, but from what I have read and tried so far I conclude that it is not impossible to have an Android phone respond to an iPhone headphone's volume buttons, but for some reason the performance is poor/lagging.
There are some apps trying to do the magic, but they are too unreliable for everyday use. I suppose the problem is that triggering the signal may have to be implemented at a lower OS level than most regular apps have access too.
The solution could probably be some kind of a ROM mod...
If you can implement this, I am sure it would be a big deal for the Android community, and maybe a good biz for you.
Kind Regards, your fellow Hungarian
Gergő

You have to press and hold the middle button while plugging the headphones to the jack. That will make the microphone work on an Android. It works on my HTC Thunderbolt.

I believe it's a hardware issue (at least in regards to Apple headphones). If you look at the plug on those they have four contacts instead of the normal three. I'm willing to bet they run their button signals through that extra contact. AFAIK, there is no Android equipment wth jacks to match that.
So, ultimately I don't believe you can make apple earphones with buttons work for android (as far as button functions go).

You have to hold the middle the whole time for it to work. If you let go and not playin music it says accsessary not supported but if u play music and let go it simply stops the music until you hold it again. Maybe tape the middle button shut really tight?

If you look at the four contacts, tip-ring-ring-sleeve (TRRS), and know that MOST headphone sets are:
tip: left
ring 1: right
ring 2: ground
sleeve: mic
(1/4 inch pro audio stereo plugs are known as TRS - tip-ring-sleeve)
although some reverse the ground and mic contacts, what you need to know as far as how the device recognizes the different buttons you have, is that those buttons are making a short between the ground and mic contacts.
(before IR, old school WIRED remotes for VCRs used resistance for different functions)
Now your homework to find out what is going on is:
measure the resistance between ring 2 and the sleeve for each one of your buttons
find out if it is a momentary short, or constant
if you have some other headphone/mic device that works correctly, measure those impedance (resistance) too
I don't know how into this you want to get, but you can buy resistors with the correct impedance to get the functions you want out of the Android device, the question is, do you know what functions the device is capable of, and what those impedances are that trigger that function.
daniel#destinypatrolsoftware.com

Android Hide mouse pointer programmatically in my own app

I know there is a similar question here: Moving mouse pointer on Android screen programatically but it doesn't seem to answer my needs (particularly because the answer was "not possible"!)
My client has an Android phone which is connected via some sort of bluetooth dongle to a wireless keyboard/trackpad. This is all working fine and I have written some software to react to keypresses. The problem is that the client is NOT interested in seeing a mouse cursor on the screen (this particular keyboard will have all except a few buttons covered up and will function as a remote control, the trackpad is inaccessible so the pointer sits in the middle of the screen uselessly).
So - is there any way for my app to get rid of the visible mouse pointer (either just for itself or for all cases, I don't care - this app is the only thing they want running on the phone). If I can't hide it can I move it to a corner, or can I change it to look like a plain white box instead of an arrow, or something else?
Any ideas would be greatly appreciated
Thanks

So - is there any way for my app to get rid of the visible mouse pointer (either just for itself or for all cases, I don't care - this app is the only thing they want running on the phone). If I can't hide it can I move it to a corner, or can I change it to look like a plain white box instead of an arrow, or something else?
All of this may be possible with custom firmware. None of this is possible via the Android SDK.
You may be better served simply by replacing the "wireless keyboard/trackpad" with one that does not have a trackpad.

android - possible to make a user action emulate the hardware 'Back' button?

I looked around and although there are many related questions I didn't see one that answers my exact question:
I would like to create an app that runs in the background that provides the exact same functionality as the hard coded 'Back' button in all cases.
The reason? I (for example) have a Droid X, and it is BIG. it makes it extremely hard to use one-handed and having a swipe gesture function as a back button (like in Palm Pre for example) would greatly increase the ease of use.
as far as I'm concerned the app could just be one simple class that contains:
1) a listener for the 'back' swipe
2) a call to the physical hard button itself
Is this possible? are there built in APIs for the hard coded buttons that would allow me to call them without actually pressing them?
Again - I'm not interested in overriding the button, I'm interested in making a software call to it - or failing that, in emulating it's behavior in any and all states and other apps!
Please forgive the naivete of this post. I am a very novice programmer and really I just want to know whether this is possible before I start to devote myself to trying to build it.
Thank you,
b

Is this possible?
By writing your own firmware, yes. Via an Android SDK application, no.