what could be resulting in the errors

Question

In navigation.java, errors:navigation is already defined in the compilation unit and cannot find symbol method findNavController(Navigation ,int)

Navigation.java

package com.example.bcuilders;

import android.os.Bundle;
import com.google.android.material.floatingactionbutton.FloatingActionButton;
import com.google.android.material.snackbar.Snackbar;

import android.view.View;

import androidx.navigation.NavController;
import androidx.navigation.Navigation;
import androidx.navigation.ui.AppBarConfiguration;
import androidx.navigation.ui.NavigationUI;

import com.google.android.material.navigation.NavigationView;

import androidx.drawerlayout.widget.DrawerLayout;

import androidx.appcompat.app.AppCompatActivity;
import androidx.appcompat.widget.Toolbar;

import android.view.Menu;

public class Navigation extends AppCompatActivity {

private AppBarConfiguration mAppBarConfiguration;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_navigation);
    Toolbar toolbar = findViewById(R.id.toolbar);
    setSupportActionBar(toolbar);
    FloatingActionButton fab = findViewById(R.id.fab);
    fab.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View view) {
            Snackbar.make(view, "Replace with your own action", Snackbar.LENGTH_LONG)
                    .setAction("Action", null).show();
        }
    });
    DrawerLayout drawer = findViewById(R.id.drawer_layout);
    NavigationView navigationView = findViewById(R.id.nav_view);
    // Passing each menu ID as a set of Ids because each
    // menu should be considered as top level destinations.
    mAppBarConfiguration = new AppBarConfiguration.Builder(
            R.id.nav_home, R.id.nav_gallery, R.id.nav_slideshow,
            R.id.nav_tools, R.id.nav_share, R.id.nav_send)
            .setDrawerLayout(drawer)
            .build();
    NavController navController = Navigation.findNavController(this, R.id.nav_host_fragment);
    NavigationUI.setupActionBarWithNavController(this, navController, mAppBarConfiguration);
    NavigationUI.setupWithNavController(navigationView, navController);
}

@Override
public boolean onCreateOptionsMenu(Menu menu) {
    // Inflate the menu; this adds items to the action bar if it is present.
    getMenuInflater().inflate(R.menu.navigation, menu);
    return true;
}

@Override
public boolean onSupportNavigateUp() {
    NavController navController = Navigation.findNavController(this, R.id.nav_host_fragment);
    return NavigationUI.navigateUp(navController, mAppBarConfiguration)
            || super.onSupportNavigateUp();
}
}

and in the mainActivity.java error:cannot find symbol class intent mainActivity.java

 package com.example.bcuilders;

    import androidx.appcompat.app.AppCompatActivity;

    import android.content.Intent;
    import android.os.Bundle;
    import android.view.View;
    import android.widget.EditText;
    import android.widget.Toast;

    public class MainActivity extends AppCompatActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
    }
    public void buttonClick(View view)
    {

        EditText et1= (EditText) findViewById(R.id.MyEmail);
        EditText et2= (EditText) findViewById(R.id.MyPass);

        String email=et1.getText().toString();
        String pass=et2.getText().toString();

        String oemail="admin";
        String opass="admin";

        if (email.equals(oemail) && pass.equals(opass)){

            Intent intent = new intent(this, Navigation.class);
            startActivity(intent);

        }
        else{
            Toast toast = Toast.makeText(this, "Invalid Email/Pass",Toast.LENGTH_LONG);
            toast.show();
        }



    }
}

errors:navigation is already defined in the compilation unit and cannot find symbol method findNavController(Navigation ,int) in Navigation.java

Does this answer your question? [What does a "Cannot find symbol" or "Cannot resolve symbol" error mean?](https://stackoverflow.com/questions/25706216/what-does-a-cannot-find-symbol-or-cannot-resolve-symbol-error-mean) — luk2302, Nov 20 '19 at 10:13

score 0 · Answer 1 · answered Nov 20 '19 at 11:02

Try below code:

1) In the mainActivity.java error:cannot find symbol class intent mainActivity.java

Instead of this

Intent intent = new intent(this, Navigation.class);

Use this

Intent intent = new Intent(this, Navigation.class);

Because you are using lowercase intent it is throwing that error.

2) In navigation.java, errors:navigation is already defined in the compilation unit and cannot find symbol method findNavController(Navigation ,int)

To solve this error rename your navigation.java to something else other than navigation. In your case it tries to find findNavController(Navigation, int) in your navigation.java class, which is not there.

Hope it solves your errors!!!

what could be resulting in the errors

1 Answers1