1. Sample
2. NavigationDrawerActivityのHomeへHello World!表示

NavigationDrawerActivityでHomeにHelloWorldを表示する方法。NavigationDrawerActivityを選択して、アプリを作成します。

通常下記のような動作のものが完成します。

Homeを選択

This is home fragmentが表示されます

サンプル

HomeFragment.java

					
						
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.TextView;

import androidx.annotation.NonNull;
import androidx.annotation.Nullable;
import androidx.fragment.app.Fragment;
import androidx.lifecycle.Observer;
import androidx.lifecycle.ViewModelProvider;

import com.example.navidrawact.R;
import com.example.navidrawact.databinding.FragmentHomeBinding;

public class HomeFragment extends Fragment {

    private HomeViewModel homeViewModel;
    private FragmentHomeBinding binding;

    public View onCreateView(@NonNull LayoutInflater inflater,
                             ViewGroup container, Bundle savedInstanceState) {
        homeViewModel =
                new ViewModelProvider(this).get(HomeViewModel.class);

        binding = FragmentHomeBinding.inflate(inflater, container, false);
        View root = binding.getRoot();

        final TextView textView = binding.textHome;
        homeViewModel.getText().observe(getViewLifecycleOwner(), new Observer() {
            @Override
            public void onChanged(@Nullable String s) {
                textView.setText("Hello World");  // ここを変更
            }
        });
        return root;
    }

    @Override
    public void onDestroyView() {
        super.onDestroyView();
        binding = null;
    }
}
				

HomeでHello Worldが表示されます。