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Broadcast Receiver for volume up button

I am aware that this question has been asked already in this site, but I could not find my answer. SO this is what i am trying ot do. My power button in my phone is not working properly. So could is there a way to override my volume up button to unlock my phone.
I am planning to implement broadcast receiver But could not find the appropriate intent-filter. Another alternative that I thought was to run a service when the screen is locked, but I am not quite sure if I can listen to key events.
So if any of the above mentioned is possible, could you hint on how to get it done or suggest another alternative?

No, It do not think so. This can not be done.

There is no broadcast for volume up or down button presently. You can implement a service that will listen for any changes in the volume but it is not recommended to run a service all the time since that consumes both battery and memory.
The only solution that I can think of is using ContentObservers for listening to the changes in the settings such as volume of streams. This answer here will provide you with the code to use ContentObserver to listen for volume up or down. https://stackoverflow.com/a/7017516/1979347

This functionality you speak of has already been done multiple times and can be found on Google Play. However, I'm not sure how they did it, or how much their solution drains the battery.
I just did a test on my G2 (Android 4.2.2), I launched a broadcast monitor, I switched to the homescreen, and I changed the volume from there.
Apparently, it can detect if the volume is turned up only when it changes from silent mode > to Vibration mode > or to Sound mode. Conversely, when pressing the down volume, I think we can detect the change when it goes from the Sound Mode > to Vibration Mode > or to Silent Mode.
This is probably not what you wanted to hear, but I just wanted to confirm what the others were saying. On a non-rooted phone, what they're saying is mostly correct. On a rooted phone however, there are custom ROMs that have solved this issue.
By the way, what brand/model is your phone? On my phone, when the headset gets connected, the phone lights up. So I suppose, one could always do it the way iPhone owners do it for their phones. You'd have to cut the extremity of a head phone jack, coat half of the pin in plastic, and super glue a button on top of it to allow you to easily twist the head.

how to detect shake event when my phone is in lock state

I read this unable to detect shake event when my phones screen is off in android article. But this question is differ from this.
I created an application which speak (using TextToSpeach API) time when I shake device. For that I have created a "Service" in which "ShakeListener" was registered. While I shake device, it will speak current time.
But this works fine while my device is "ON". When I lock my device, it stops working. Can any one elaborate what is the problem behind?

I think the problem here is that when you lock the device, it goes to sleep mode. And your ShakeListener doesn't receive shake events. The best way to implement what you want would be to register broadcast receiver to receive shake events. But as I know, android doesn't provide such broadcast. Another solution is to acuire a partial WakeLock. It'll prevent android from sleep. But of course it'll cause battery issues. Also take a look on this thread: Android accelerometer not working when screen is turned off

Probably you can not receive this notification until you patch some kernel implementation. Android doesn't broadcast such notification.

Check volume button usage when screen is off

For this question I'm going to quote another user who got no response to their question:
I've written an Andoid app that uses the hardware Volume buttons for another purpose.
It works fine if the app is running and visible, but when I turn the
screen off or let it time out, the button clicks don't get into my
handlers.
Does anyone know if there is a way to detect these button clicks when
the screen is off?
Source: AV695's question
I'm working on an app myself that makes use of the volume buttons, but as this user also noted, the normal behavior of checking buttons with onKeyPress stops working once the screen is off. This is because the Activity gets paused on screen off.
Is there a way to keep the activity running while the screen is off, or check for the usage of the volume buttons when the screen is off? I tried using a Service for this before but it's impossible to check for the volume keys like that as noted by Commonsware.

I doubt that this is supported (without resorting to a battery-draining wakelock) at either the platform, kernel, or underlying radio firmware levels without modifications to the last to bring volume presses during sleep to the attention of the kernel.
Within the realm of reasonable system-ROM modifications, a more reasonable one might be to modify an existing open source ROM for the device to insert some custom platform level code into the handling of the power button usually used to wake up the device preparatory to unlocking it - that at least we know does get the attention of the kernel. That code could then inform the user by sound or vibration if there are unacknowledged notifications.
You could optionally wait briefly, check device orientation, or look for another key press to avoid doing this in an annoying way when the user is holding the device outside their pocket and trying to unlock it.
Or you could not use the volume key and just set a timer to wake up every 15 minutes and vibrate if there are unacknowledged notifications, avoiding the need to fumble in ones pockets.
You mention it's a custom request: if implies it's one off or low-volume, another option to consider would be that a few vendors have "bluetooth watches" out with an SDK that lets you push notifications from an android device.
If you can capture the notification when it's generated, you could push it to the user's wrist, and then let the phone go back to sleep.

You cannot intercept the key while your application is in background, but instead of listening to the KeyPress itself. You can register a ContentObserver, as described in this question.

As Chris Stratton mentioned, the only way to keep your App alive is by using battery-draining wake locks.
However, since I found myself in the same situation, I came up with another solution. Unfortunately, you'll need a rooted device as well as the Xposed framework.
With Xposed, which replaces the zygot process so you can hook yourself into any constructor and method of the system, you will be able to catch the raw KeyEvents before the system handles them.
This is done in PhoneWindowManager.interceptKeyBeforeQueueing(). By using a XC_MethodHook, you can use beforeHookedMethod() on the afore mentioned method to catch every hardware button event, even if the device is in deep sleep.
After catching events you are interested in, you can create a temporary wake lock to do your things but don't forget to release the wake lock after you finished your work.
A good example of how to accomplish this is the Xposed Torch Module.
If you, however, rely on a non rooted system, the bad news is that it's simply not possible without draining the battery...

I was also trying to implement volume button press detection in my app and I left that part to be developed later once the core part is done. I was able to detect volume key press while screen is on even when phone is locked, from a background service.
Background Video Recorder 2 (BVR2) (and possible BVR1 also, I did not try) is one of the apps that can detect volume key press even when screen is off. While trying to implement volume key detection while screen is off in my app, I installed BVR2, hoping to find how it works. To my surprise it gave my app the ablity to detect volume keys even when screen is off. My app had a ContentObserver to monitor volume changes, but was not working when screen is off. When BVR2 is active my app also could detect volume key press when screen is off. Still digging.
But BVR2 has its own trigger action, that is to record video, an action you may not want to occur just for the sake of you application detecting volume key presses.
Another app is QuickClick. This app can give your app what it lacks, the power to detect volume key presses even when screen is off, without extra unwanted actions. Just install QuickClick and do not configure any action. Create a ContentObserver to monitor for stream volume changes and you are ready. You app will now be able to detect volume key presses even when screen is off.
Please note that my app runs as a background service.
Both of the apps mentioned above are meant for other uses, but uses volume key detection to perform action. I am in no way connected to any of the apps mentioned.
If these apps, and possibly dozens others, can detect volume key press, it can be done. I request experts to find out how to do it, so that we can implement in our app without relying on another app.
If you find this answer useful, please up-vote.

I am not sure if it is as simple as this but check this android blog:
Allowing applications to play nice(r) with each other: Handling remote control buttons
It explains the usage of a broadcast receiver that receives the up/down volume controls and other music controls.
In summary you should use registerMediaButtonEventReceiver

Key events in Android services

I've made some research concluded that afaik I can't have an Android service for key events capture. But - maybe some will have any workaround. I have a player application, which i want to play/pause using a special button on my earphones (included for my samsung galaxy S). This is button for reciving and ending phone calls set on phones cable.
Ive tested this button - it equals KeyCode.KEYCODE_BUTTON_B const (79). And it can be handled when my player is on screen, but I'd like to play/pause also when my phone is locked (with screen off). Do You think this is possible?
For call reciving I think android uses a trick: when someone calling, the screen goes active, and the call-reciving activity can handle key events (I think - this is how it's work, but I can be wrong).
I have no idea - how to play/pause my app using this button.

I don't think there is any real good way to achieve what you want to do from the application level. However one possible solution I can come up with is this:
Listen for screen off and on Intents. When you receive SCREEN_OFF start up a "blank" activity that does nothing but listen for your button press and passes it along to your music service.
When you recieve SCREEN_ON finish() this blank activity.
I don't know for sure that this approach will work, but I used something similar to be able to listen for volume button presses while the screen was off.
Note about listening for SCREEN_OFF and SCREEN_ON intents. When I did this I had to set the filter for my receiver in java code rather than in the manifest. For some reason when I set the intent filter from the manifest it wasn't receiving those intents properly.

Creating 'middleman' headset button controller in Android

All,
I have searched for an answer to this, but I'm not getting anything exact... It's my first time writing an Android app, so please be gentle :)
I'm pretty bummed about the minimal headset support in Android - unlike e.g. iPhone, it only natively seems to support a single button, so no volume control on headset compatibility. Additionally, if I'm listening to music and a call comes in, the OS pauses the music automatically, but the headset button still functions ONLY as a media button - I can't use it to answer/end the call. If I answer the call via the screen and press the headset button, the music starts again, but the call continues...
I'd like to create a 'middleman' app that can pick up that the headset button has been pressed (via Keyevent.KEYCODE_HEADSETHOOK) and can then determine whether to perform the default ACTION_MEDIA_BUTTON action (toggle play/pause in my chosen media player) or, if there is an incoming call, pause the music and answer the phone (and then, when pressed again, end the call and restart the media player). Perhaps even check for ACTION_MULTIPLE on the headset button to assign different options (ACTION_MEDIA_NEXT, ACTION_MEDIA_PREVIOUS etc.). Perhaps also be able to determine whether different buttons on the headset have been pressed (if the headset is e.g. a fancy iPhone headset) and 'translate' those button presses into the appropriate ACTION_MEDIA_*). This might not be possible if the OS can't tell the difference between different buttons, obviously.
Obviously such an app would have to receive the intent with a high enough priority that it would be able to abort the broadcast before the current media player gets it.
I've been tinkering with creating assorted BroadcastReceiver classes and intent filters etc., but part of the problem is that the bult-in Android emulator that comes with Eclipse doesn't seem to have the ability to simulate a user plugging in the headset and/or subsequently clicking the headset button. Therefore, every time I get somethign that looks promising, I have to put it onto my actual phone and try it out - time-consuming and a hassle.
3 questions then:
Am I missing somethign obvious - is this a real problem and if so, has it already been solved?
If it IS a problem, is it possible to write such a middleman app?
Are there any other Android emulators that can check for headset-related activities?
Thanks,
Rory

i´ve already written exactly this kind of app. Its called like the topic of this thead: Headset Button Controller ;-)
http://www.androidpit.com/en/android/market/apps/app/com.kober.headset/Headset-Button-Controller
Cheers Christoph