使用ImageView onClick在HomeFragment中打开在MainActivity中创建的DrawerLayout，避免NPE

<ImageView
    android:id="@+id/imageView"
    ... />

public class HomeFragment extends Fragment {

    private ImageView imageView;
    private MainActivity mainActivity;

    @Override
    public void onAttach(@NonNull Context context) {
        super.onAttach(context);
        if (context instanceof MainActivity) {
            mainActivity = (MainActivity) context;
        } else {
            throw new RuntimeException("MainActivity is not attached!");
        }
    }

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
        View view = inflater.inflate(R.layout.fragment_home, container, false);
        imageView = view.findViewById(R.id.imageView);
        imageView.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                if (mainActivity != null) {
                    mainActivity.openDrawer();
                }
            }
        });
        return view;
    }
}

public class MainActivity extends AppCompatActivity {

    private DrawerLayout drawerLayout;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        drawerLayout = findViewById(R.id.drawerLayout);
        // 其他初始化操作...
    }

    public void openDrawer() {
        if (drawerLayout != null) {
            drawerLayout.openDrawer(GravityCompat.START);
        }
    }
}