"This class was probably produced by a compiler that did not target the modern .class file format"

Hi guys, Does anybody know anything about this problem? I’m getting this during compilation. The app runs fine, but this is somewhat disturbing as it appears as an error and adds to the error count… :\

Error:warning: Ignoring InnerClasses attribute for an anonymous inner class
Error:(com.qozix.tileview.TileView$1) that doesn't come with an
Error:associated EnclosingMethod attribute. This class was probably produced by a
Error:compiler that did not target the modern .class file format. The recommended
Error:solution is to recompile the class from source, using an up-to-date compiler
Error:and without specifying any "-target" type options. The consequence of ignoring
Error:this warning is that reflective operations on this class will incorrectly
Error:indicate that it is *not* an inner class.

Error:warning: Ignoring InnerClasses attribute for an anonymous inner class
Error:(com.qozix.tileview.TileView$SavedState$1) that doesn't come with an
Error:associated EnclosingMethod attribute. This class was probably produced by a
Error:compiler that did not target the modern .class file format. The recommended
Error:solution is to recompile the class from source, using an up-to-date compiler
Error:and without specifying any "-target" type options. The consequence of ignoring
Error:this warning is that reflective operations on this class will incorrectly
Error:indicate that it is *not* an inner class.

Error:warning: Ignoring InnerClasses attribute for an anonymous inner class
Error:(com.qozix.tileview.tiles.TileCanvasViewGroup$1) that doesn't come with an
Error:associated EnclosingMethod attribute. This class was probably produced by a
Error:compiler that did not target the modern .class file format. The recommended
Error:solution is to recompile the class from source, using an up-to-date compiler
Error:and without specifying any "-target" type options. The consequence of ignoring
Error:this warning is that reflective operations on this class will incorrectly
Error:indicate that it is *not* an inner class.

I’m testing this on:

• API 23 device (ASUS Zenfone 2 Z00A).
• Android Studio 2.1 preview 5.
• 'com.android.tools.build:gradle:2.1.0-alpha5'
• 'com.google.gms:google-services:2.1.0-alpha4'
• 'com.qozix:tileview:2.1.2'
• Gradle 2.12
• And also:

compileOptions {
    sourceCompatibility JavaVersion.VERSION_1_8
    targetCompatibility JavaVersion.VERSION_1_7
}

[moagrius]

i think that might be a proguard thing…? i’m really not sure though, i’ll leave this open until i get some time to poke around

[moagrius]

i’m not seeing any similar warnings on an app using 2.1.5, so closing it.

thanks @Dev-iL for posting!