Develop Reference

Kotshi issue - unresolved reference for KotshiApplicationJsonAdapterFactory

So I'm trying to follow the simple read.me for Kotshi and get it set up for my project but I seem to be hitting a little snag.
I'm currently at this portion of the read.me
#KotshiJsonAdapterFactory
object ApplicationJsonAdapterFactory: KotshiApplicationJsonAdapterFactory()
but KotshiApplicationJsonAdapterFactory seems to give me an unresolved reference error. Now this sounds like an absolutely silly question but is KotshiApplicationJsonAdapterFactory supposed to be a custom class that I set up? If so I don't see anywhere in the documentation regarding it. My gradle has the two dependencies added so I'm absolutely baffled.

#KotshiJsonAdapterFactory makes Kotshi generate a JsonAdapter factory.
Should be placed on an abstract class that implements
JsonAdapter.Factory.
So yes, KotshiApplicationJsonAdapterFactory is a custom class that you've to setup and which fulfills the above condition.

KotshiJsonAdapterFactory is an annotation that you apply to a class that you write. This will make Kotshi generate a class with the same name as your class + the Kotshi prefix. That class will implement the actual factory.
When you write your class it will look like you have a compile error, but it will not prevent compilation.

Cannot reference class from another class in same package

I'm admittedly new to Scala and Android programming and in all my searching I haven't been able to find answer to help me understand and resolve my problem.
Here's a gist of my two scala classes https://gist.github.com/Daikamar/f15288a7bf732cd5b55c
I'm running through the tutorial found here: http://developer.android.com/training/basics/firstapp/starting-activity.html
which I'm trying to adapt to scala code (I have need for understanding Scala for work and a personal desire to mess around with Android development so I figured I'd try and combine these efforts).
The problem is seen in DisplayMessageActivity.scala in which the IDE reports that it cannot resolve MyActivity in this line:
val message = intent.getStringExtra(MyActivity.ExtraMessage)
I feel like this should work. I can get it to resolve if I change MyActivity to an object, but then that breaks other pieces of the application that expects MyActivity to be a class.
An help in getting me to understand my problem would be appreciated.

You cannot reference the ExtraMessage field from MyActivity as though it was a 'static' field (in Java terminology). To access ExtraMessage in your other activity you will need to either obtain an instance of MyActivity that you can then de-reference, or add a companion object (defined using the object keyword in the same file in which the class is defined) for MyActivity and define the field there:
object MyActivity {
val ExtraMessage = "net.daikamar.myfirstapp.MESSAGE"
// any other 'static' declarations
}
class MyActivity() extends ...
then your call as above will work.

Linking android (Java) to chromium (cpp) with JNI

I'm trying to modify chromium on android for research purposes.
Chromium comes with a ContentViewCore.java class. This class calls a native function:
nativeEvaluateJavaScript(mNativeContentViewCore, script, null, true);
This method is defined in the same class as follows:
private native void nativeEvaluateJavaScript(long nativeContentViewCoreImpl,
String script, JavaScriptCallback callback, boolean startRenderer);
The class has the following annotation:
#JNINamespace("content")
As I understand it, the JNI Generator links these methods to the correct native (c++) methods of the correct class.
My question: To which class is ContentViewCore.java linked? Where can I find the implementation of nativeEvaluateJavaScript? Where is it defined that a specific java class is linked to a specific c++ class?
The only thing I can find is content_view_core.h (src/content/public/browser/android), but that file doesn't get me any further. Googeling for 'nativeEvaluateJavaScript' revealed nothing. I've been searching for about 10 hours now and I'm not getting any closer.

The JNI generator will generate JNI binding file under "(SHARED_INTERMEDIATE_DIR)/<(jni_gen_package)/jni/" during the build time.
For example, the corresponding JNI binding file for ContentViewCore.java is "out/Debug/gen/content/jni/ContentViewCore_jni.h". And you can see the native method of 'nativeEvaluateJavaScript':
static void EvaluateJavaScript(JNIEnv* env, jobject jcaller,...

method in android which can be accessed from anywhere?like modules in VB

I am new to android. If my question is wrong please forgive me,
My Question is:
Can I write a method in android which can be accessed from anywhere inside my application?
I've studied VB for all these years and now I am trying to program in android, I couldn't stop comparing them when I write code.
In VB we can create modules and access it from anywhere. Is there anything I can do in Android...??
Answers and advises are needed!

You have to create a class with a static method:
public class MyClass {
public static void myMethod() {
// Your code here...
}
}
And you can call it like this: MyClass.myMethod();

You can try extending Application and put your common functions there.
In all activities you can access this via context.
For reference follow this:
http://www.devahead.com/blog/2011/06/extending-the-android-application-class-and-dealing-with-singleton/

It is a long topic to discuss , but as you have simply ask whether method is accessible or not , then answer is yes but with some respect of java rules.
Android is again like java coding, You can do same thing what we can do with java.
Same Data type
Method Format
Class structure
Inheritance, Public , private , protected, etc.
So while you write your code you should care for that all things and these all thing you know because you are working in VB.

VB module equivalent is not there in java(android),
but some how you can mock them to some extend by using final classes with static methods.
Anyway you need to import the package containing these type of classes wherever you use it.

cannot use external JNI function in two different classes, unsatisfied link error

For an Android application, I have implemented an external function in C, which I would like to use in two separate classes.
In the first class (my main Activity UI), I call the appropriate loadLibrary:
System.loadLibrary(...);
In the same class, I define the function as native:
public native int dissectPacket(byte[] header, byte[] data, int encap);
After doing this, I can call the native function with no problem in the first class. I do not get any unsatisfied link error.
Now, I want to use this function in another class. I figure I do not need to load the library again. In the second class, at the bottom, I also define:
public native int dissectPacket(byte[] header, byte[] data, int encap);
However, when I try to use the native function in the second class, I get:
07-22 23:13:13.083: ERROR/AndroidRuntime(6737): Caused by: java.lang.UnsatisfiedLinkError: dissectPacket
What is the proper way to use the function in both classes? If I do not redefine the function as native in the second class (called Packet), I get the error:
The method dissectPacket(byte[], byte[], int) is undefined for the type Packet
BTW, I do NOT want to use: class1.dissectPacket(...); I am trying to avoid passing the class.

You defined actually two separate functions. One for the first class and another one for the second. They will need two separate JNI stubs. You, probably, only have stub and implementation for the first one.
JNI and Java, in general, always refer to methods of the specific class.

"BTW, I do NOT want to use: class1.dissectPacket(...); I am trying to avoid passing the class."
If you want to do that, the member functions need to be static, otherwise the class is implicitly passed as a parameter (I don't know how because I've never done it, static functions have always worked for me, but it has to happen to work properly).
So change your method stubs to:
public static native int dissectPacket(byte[] header, byte[] data, int encap);