Android Studio Plugin

What do you mean by "injecting code"? Could you give a sample?

yes, of course. For example, I have this activity that is called login activity

public final class LoginActivity extends AppCompatActivity {

private AuthorizationService mAuthService;
private AuthStateManager mAuthStateManager;
private Configuration mConfiguration;

and it has the onCreate() method.

the work that I want to do is that:
- find the onCreate() method inside login activity 
- Insert some code inside the activity from a txt file or template file that stored inside the plugin (I make the code that should be inserted within the method bold)

protected void onCreate(Bundle savedInstanceState) {

if (mAuthStateManager.getCurrent().isAuthorized()
        && !mConfiguration.hasConfigurationChanged()) {
    Log.i(TAG, "User is already authenticated, proceeding to token activity");
    startActivity(new Intent(this, TokenActivity.class));
    finish();
    return;
}
}

thank you in advance

Ok, you will need to navigate through PSI and then insert the text into Document:

https://www.jetbrains.org/intellij/sdk/docs/basics/architectural_overview/psi_files.html

https://www.jetbrains.org/intellij/sdk/docs/basics/architectural_overview/documents.html#what-are-the-rules-of-working-with-documents

Good luck!

Okay. Thank you for your help. one more question, Template files are not supported in community edition?

Template files are supported in Community as well.