Proguard Leads To Nullpointerexception

When setting minifyEnabled true in my gradle I get a NullPointerException when starting my app: java.lang.RuntimeException: Unable to start activity ComponentInfo{de.ae.formulaec

Solution 1:

It's likely that this happens, when serializing objects and the fields are not annotated by @SerializedName("param") (or similar) and therefor can not be found.

For debugging it also helps to temporarily set -keepnames class ** so that the class names are not obfuscated.

Solution 2:

The idea is to keep the files provided from the libraries you included in your project. I'm sharing one of my proguard-rules.pro which might help you to understand.

-keep classcom.google.** { *; }
-keep classcom.github.** { *; }
-keep classorg.apache.** { *; }
-keep classcom.android.** { *; }
-keep classjunit.** { *; }
-keep classandroid.support.v7.widget.SearchView { *; }
-keep classcom.myproject.model.** { *; }

Hope that helps!

Solution 3:

For me, adding lines (you may have other name for package where you put your POJO files):

-keep class [mypackagename].model.** { *; }
-keep class [mypackagename].datamodel.** { *; }

to proguard.rules worked perfectly, then options:

android
{
    ...
    buildTypes {
        release {
            minifyEnabled true 
            shrinkResources true
        }
    }
}

are set in build.gradle (Module: app)

Solution 4:

most of the time the error because of android libs, try this

-keep interface android.support.** { *; }-keep class android.support.** { *; }

Solution 5:

I solved the problem:

After running Clean Project in Android Studio I got an error about a file called resource-release-stripped.ap_ that cannot be found. Some searching via Google showed up that I need to disable shrinkResources in the gradle file because it is not compatible with Jack.