Sending commands to voice assistant from Android app

In order to increase efficiency I want to send frequently used commands to Google Assistant from an Android app via script. E.g. "Ok, Google .

This is the code I use for calling Assistant from a Service:

startActivity(new Intent(Intent.ACTION_VOICE_COMMAND).setFlags(Intent.FLAG_ACTIVITY_NEW_TASK));

I have found this topic, which says that this is not possible for Raspberry Pi which uses Google Assistant SDK. Is it the same for Android apps?

UPDATE: Does not work with Google Assistant. It only worked with Google Now.

Managed to make it work:

String command = "navigate home by public transport";
Intent intent = new Intent(Intent.ACTION_WEB_SEARCH);
intent.setClassName("com.google.android.googlequicksearchbox", "com.google.android.googlequicksearchbox.SearchActivity");
intent.putExtra("query", command);
intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK); //necessary if launching from Service
context.startActivity(intent);

Source: StackOverflow question