Android: able to install app for unsupported Android version

Question

We're dropping support for Android 2.3 (API level 9) devices because most of our users have a newer Android version on their phones. I've updated the minimum SDK version to api level 14.

android {
    compileSdkVersion 23
    buildToolsVersion "23.0.2"

    defaultConfig {
        minSdkVersion 14
        targetSdkVersion 23
    }
}

However I'm still able to install the app on Android 2.3 devices manually (not by store). Is this expected behavior or am I doing something wrong? I couldn't find the answer somewhere else.

Another strange issue is that Lint doesn't detect the correct api level.

listView.setFastScrollAlwaysVisible(true);

This results in the warning: Call requires api level 11 (current min is 9). However my current minimum is now 14. So this indicates to me that i did something wrong. I tried cleaning and rebuilding the project, restarting Android Studio. It all didn't work.

Can anyone help me out?

Edit

Based on Sufians comment I started fiddling around with my gradle files and I came to the following solution. However some questions still remain. My project structure looks like this:

• android.gradle (top-level build file which contains SDK versions)
• main module (contains base code for other modules)
  • build.gradle (apply from: '../android.gradle')
• sub module A (module specific changes)
  • build.gradle (has dependency on main module)
• sub module B (module specific changes)
  • build.gradle (has dependency on main module)

I have a top-level build file android.gradle which contains the SDK versions. My modules then include the build file by apply from: '../android.gradle'. If I put the minSdkVersion directly in de main module the warnings disappear. Is that the way it should be? or do I need to set an minSdkVersion for every submodule? Or is there another way so that the SDK versions can stay within the android.gradle file?

Answer 1

Ok... I finally realized that there is nothing wrong in my project structure. The only thing I needed to do was press the little 'Sync Project with Gradle Files' button. After that all errors disappear.

Also I concluded that it's possible to install unsupported apps manually. However the Google Play Store should prevent users from installing or updating the app.