code: private void obtainSummaryOff(@NonNull final TypedArray typedArray) {
          setSummaryOff(
                  typedArray.getText(R.styleable.AbstractTwoStatePreference_android_summaryOff));
      }
docs: Obtains the summary, which should be shown when the preference is not checked, from a
  specific typed array.
  
  @param typedArray
  The typed array, the summary should be obtained from, as an instance of the class
  {@link TypedArray}. The typed array may not be null