Unchecked call to 'setPicker(List)' as a member of raw type 'com.bigkoo.pickerview.view.OptionsPickerView'

IDE:Android Studio 3.2.1

android {
compileSdkVersion 28
defaultConfig {
applicationId "com.name.name"
minSdkVersion 16
targetSdkVersion 28
versionCode 2
versionName "0.0.2"
testInstrumentationRunner 'androidx.test.runner.AndroidJUnitRunner'
vectorDrawables.useSupportLibrary = true
}

implementation 'com.contrarywind:Android-PickerView:4.1.6'

public List mDatas;

public OptionsPickerView pvOptions;

mLevelDatas = new ArrayList<>();
for (int i = 1; i < 20; i++)
{
mDatas.add(i);
}
pvOptions = new OptionsPickerBuilder(Activity.this, new OnOptionsSelectListener()
{
@OverRide
public void onOptionsSelect(int options1, int option2, int options3 ,View v)
{
level = mDatas.get(options1);
//do something;
}
}).build();
pvOptions.setPicker(mDatas);

the last line of code gives a warning:
Unchecked call to 'setPicker(List)' as a member of raw type 'com.bigkoo.pickerview.view.OptionsPickerView'

Any idea?