The hasFragileUserData flag can be added to the application node of AndroidManifest.xml. If its value is true, then when the user uninstalls the app, a prompt will be shown to the user asking him whether to keep the app's data.
<application
...
android:hasFragileUserData="true" tools:targetApi="q">
...
</application>
For a brief user-level introduction to CMake, watch C++ Weekly, Episode 78, Intro to CMake by Jason Turner. LLVM’s CMake Primer provides a good high-level introduction to the CMake syntax. Go read it now.
After that, watch Mathieu Ropert’s CppCon 2017 talk Using Modern CMake Patterns to Enforce a Good Modular Design (slides). It provides a thorough explanation of what modern CMake is and why it is so much better than “old school” CMake. The modular design ideas in this talk are based on the book [Large-Scale C++ Software Design](https://www.amazon.de/Large-Scale-Soft
A good commit message looks like this:
Header line: explain the commit in one line (use the imperative)
Body of commit message is a few lines of text, explaining things
in more detail, possibly giving some background about the issue
being fixed, etc.
The body of the commit message can be several paragraphs, and
please do proper word-wrap and keep columns shorter than about