RxBinding | Easy oneway bindings for Android | Reactive Programming library

When you do toDoDao.insert(someToDo), you must ask yourself, how is this code working? abstact interface functions can't be called, then where is the implementation of insert(ToDo) function?

Implementation of all the functions defined in the @Dao interface is in the YourDao_impl (impl is short for implementation, implementation of your @Dao interface) which is automatically generated by the room annotation processor.

To appreciate the use of _impl class you must understand that When reading or writing to SQL databases, there are multiple steps that needs to be performed almost always. in most cases these steps would look as following:

If the app works in debug but not in release, it's probably because Proguard minified your classes and deserialization no longer works due to different (shorter) class and property names.

Make sure you have this in your proguard:

Dependencies: ./gradlew :dependencies

Some libraries will require particular versions of Kotlin, typically if they depend upon newer language features (e.g., coroutines in Kotlin 1.3).

In your case, androidx.room:room-testing:2.1.0-alpha04, through its androidx.room:room-migration:2.1.0-alpha04 dependency, wants Kotlin 1.3.0 or higher, but your project is set for Kotlin 1.2.71.

The typically-simple solution is to bump your Kotlin version. In a typical current Android Studio project, that is set in an ext.kotlin_version line in the buildscript closure of the top-level build.gradle file. Otherwise, hunt around your Gradle build scripts and properties files, looking for 1.2.71. Replace it with 1.3.0 or higher — as of late April 2019, the latest production Kotlin version is 1.3.30.

If upgrading your Kotlin version causes other problems, such as failed tests, you could elect to downgrade the dependencies that are calling for the higher Kotlin version. Eventually, though, you will want to resolve the problems and get on a current Kotlin version.

With the hot key "CTRL + Shift + F" try to search for "compile" keyword.If there is no modification left, please go to file -> Invalidate Caches/Restart.These error messages will be gone.

Since you are developing using Android Studio 3.1.3, try to update your build.gradle dependencies and plugin as well to their latest version.

And move your repository google() to the buildscript.

You can try this:

Top-level build.gradle

This code is OK.

From RxBinding::Ptr T can't be deduced, as it's a non-deduced context because of nested types (see example 1) under Non-deduced contexts on cppreference and godbolt example), so the original example shouldn't have worked with argument deduction. With that in mind having typename RxBinding::Ptr ...args will work the same way as it did before (note the syntax having ... before the argument name). I changed the variadic type template to Ts instead of T, to better represent that it's variadic.

With auto binding = makeValueBinding(std::make_tuple( /* what do do here with args ?? */ )); you can use a pack expansion with the pattern args->Get(), so the final line will be
auto binding = makeValueBinding(std::make_tuple(args->Get()...));.

Creation of the variables s0, s1, and so on is not trivial, so I'll get back to it at the end.

To make the final subscribtion, you will need to use a helper function to expand the tuple:

I found an issue: One of my packages name vas cvs - seems it is after Gradle 3.2.+ it is reserved word.