Develop Reference

Interpreting iOS code to get Bluetooth Low Energy data on Android

I was sent iOS C code to get data from a Bluetooth Low Energy scale and I need to find out how to create similar functions into Android Java code.
The scale I am working with aren't using typical UUIDs and formatting.
I already have a scanner set up with the ability to write and listen to notifications.
What I need to do is figure out how to get the weight data.
I know is that 0XFFF0 is the service UUID, 0XFFF1 is the write characteristic and 0XFFF4 is the notify characteristic.
I'm guessing it writes something, then the scale gives you the data. But I'm not sure what.
Plus I think the scale sends the data with NSUTF8StringEncoding if I'm reading it correctly. How would I implement this on Java?
Here is the code sent to me:
http://www.anj.fyi/BTManagerlib.m (I tried to post the code here, but it's registering as spam for some odd reason)
I really appreciate the help guys.
Many thanks.

"The scale I am working with aren't using typical UUIDs and formatting."
Yes, it uses, except it is written in 16-bit format If you want 128-bit UUID use XXXXYYYY-0000-1000-8000-00805F9B34FB base to create it.
From the example that you have posted:
-(void)writeDataToBlue:(NSNotification *)note
{
id obj = [note object];
_senddata = obj;
[self sendBlueToothData:_senddata showAlert:YES];
}
it is clear that data to be written to the device are not bundled into the source code, but they are received via notification center, from some other class. Ask them for device documentation or full source code, otherwise you won't be able to make any conclusions.

Accessing raw GPS data on Android

first question here!
I am interested in acquiring raw GPS data on android devices: satellite positions, pseudoranges, and phase information. According to this well-answered question, the best we can do is get everything that GpsSatellite provides.
I'm wondering if the situation has changed in the past five years? I noticed that the Android source now a structure named GpsMeasurement, which sounds like it has everything I want in it, and is used similar to the well-known GpsStatus structure.
However, GpsMeasurement is #SystemApi and thus not accessible via normal app writing. Further, I can't find any information on this beyond source code.
Is there not another way to get this data? Is there a workaround to access GpsMeasurement regardless? There's really nothing in there that should be kept from developers.

So looks like this has changed recently. Here is a link describing how to get the raw GPS data off of modern smartphones: Raw GNSS Measurements

I doubt that you ever will have access to that data on an consumer android handy.
The reason is, that the GPS chip has to specially configured to output these pseudo ranges, this produces overhead that normally nobody uses.
Further GPS chips that are able to output pseudeoranges, are often more expensive.
This is called the "raw-data option".

How to save map data in a tilebased game

I have a bit of a rookie question regarding storage of map data i a java game. I'm making a 2d tile-based game, where each tile has an id (1, 2, 3, 4 and so on...). I currently store the game data in a .txt file, where each number is seperated by a tab. Therefrom i read it via scanners .nextInt.
This method works fine, but it seems to give me a problem:
Since the level file is just a normal .txt file it is easily edited by anyone. This means that the user could just change a few numbers in the file with any kind of text editor and thereby easily cheat.
How would this be avoided? Should i store the map data differently or should i use some form of encryption?

One solution to this would be to store the data in a database, such as derby. Once the game has been exported as a jar file the casual player will never even see the file, and if they do get their hands on it, probably wouldn't know what to do with it.
Here is a nice tutorial on how to set up and connect to a simple derby database.
http://www.vogella.com/tutorials/ApacheDerby/article.html
good luck.

Java has a Serializable interface that can be used to save java objects.
API docs can be found here: http://docs.oracle.com/javase/7/docs/api/java/io/Serializable.html
This doesn't make it impossible for people to cheat and change the maps just more difficult.
If you're really worried about it you could use some form of encryption or add a checksum to further prevent tampering.

Since when is the phone charging/discharging

I wanted to learn more about the Android Services / Broadcasts, so I started a simple project, to create a battery monitoring app. It turned out pretty good, I'm using it for a few days now, but I want to add a new function: to show since when is the phone charging/discharging.
First I thought that I would create two static fields in my BoradcastReciever extension class, where I get and publish the data about the battery, one for the actual state (charging/discharging), and one for the time, when the change in state happened. This way, I could just subtract from the current time the last change, and know exactly since when is the phone charging/discharging.
But there is a problem with this solution: It won't show the correct data at first, when a user starts the app. I wouldn't make a big deal of it, but I saw that Android tracks this data somewhere, because inside my phone settings I found this information, so why take the hard way.
So my question is: is there an easy way to get from the Android system the date/time (no matter what format) of the last charging state change?
I looked at the BatteryManager reference but there are no constants named after what I seek, and which I could use, to get the information from the Intent of my receiver.

The Android OS tracks the connect/disconnect of a power source, but does not make this data accessible to apps. You have to record this all yourself, using intent filters.
The two intent filters to use are android.intent.action.ACTION_POWER_CONNECTED and android.intent.action.ACTION_POWER_DISCONNECTED; with these, you can monitor when the power source is connected and disconnected.
You can find information about this process explained incredibly clearly here. Another blog describing the process can be found here.

Best way to store text data in an android app?

I've made an Android application which contains most used German words and sentences. The application contains a CSV file which stores all the data.
Currently it is working as expected but I want to ask if there is a better way to store such data directly in the app?
I'm also thinking about the ability to update the data via internet like adding new words and sentences.
Thanks!
Miretz

If you want to modify the content (update, remove etc.) I would suggest using SQLite DB which has a pretty nice built-in integration with the Android platform.

There are 2 types SQLDatabaseLite and SharedPreference. Major difference between both is that one is organized and the other not so.
If you need a quick use of a storage facility within your app for example changing text sizes between activity SharedPrefference works best for you.
If you have a complex database system where you need more than one data to be saved for a particular event SQLDatabaseLite is for you example of this is spreadsheet of data for customers; Name, Phone Number, etc.