When declaring 'public class MainActivity extends Activity implement OnClickListener'

Question

MainActivity is highlighted and an error is presented 'The nested type MainActivity cannot hide an enclosing type' Any help solving this issue would be appreciated. when i remove the first MainActivity the rest of the code becomes filled with errors?

package com.example.myfirstapp;

import android.os.Bundle;
import android.support.v7.app.ActionBarActivity;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.widget.EditText;


public class MainActivity extends ActionBarActivity {
public final static String EXTRA_MESSAGE = "com.example.myfirstapp.MESSAGE";

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


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

@Override
public boolean onOptionsItemSelected(MenuItem item) {
    // Handle action bar item clicks here. The action bar will
    // automatically handle clicks on the Home/Up button, so long
    // as you specify a parent activity in AndroidManifest.xml.
    int id = item.getItemId();
    if (id == R.id.action_settings) {
        return true;
    }
    return super.onOptionsItemSelected(item);
}

public class MainActivity extends Activity implements OnClickListener {

    EditText fuelCost;
    EditText distance;
    EditText milesPerGallon;

    Button btn_1;

    TextView result;

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);

        fuelCost = (EditText) findViewById(R.id.fuelCost);
        distance = (EditText) findViewById(R.id.distance);
        milesPerGallon = (EditText) findViewById(R.id.milesPerGallon);

        btn_1 = (Button) findViewById(R.id.btn_1);

        result =(TextView) findViewById(R.id.result);

        btn_1.setOnClickListener(this);

    }

    @Override
    public void onClick(View v) {
        float num1 = 0;
        float num2 = 0;
        float num3 = 0;

        float result = 0;

        if (TextUtils.isEmpty(fuelCost.getText().toString())
                || TextUtils.isEmpty(distance.getText().toString())
                || TextUtils.isEmpty(milesPerGallon.getText().toString())) {
            return;
        }

        num1 = Float.parseFloat(fuelCost.getText().toString());
        num2 = Float.parseFloat(distance.getText().toString());
        num3 = Folat.parseFloat(milesPerGallon.getText().toString());

        switch (v.getId()) {
        case R.id.btn_1:
            result = ((num1 * 4.5461) * (num2 / num3)) / 100;
            break;
        default:
            break;
        }

        result.setText("£" + result);
    }       
}

}

pick one of http://stackoverflow.com/questions/9246246/nested-type-cannot-hide-an-enclosing-type http://stackoverflow.com/questions/15188196/errors-in-mainactivity-java and see if you can spot a similar error in your code. — zapl, Nov 20 '14 at 11:41

score 0 · Answer 1 · answered Nov 20 '14 at 11:44

0

You are probably declaring Main activity twice in the same activity file. Simply remove the wrong declaration.

answered Nov 20 '14 at 11:44

Machado

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Searching for the same question in other stackoverflow questions lead to the same conclusion. There must be an inner class with the same name. – Tharaka Devinda Nov 20 '14 at 11:44
There is another MainActivity defined but removing this causes more errors – Rhys Window Nov 20 '14 at 11:48
Remove the first one, it will work. Work on these errors, they are simple ones. If you can't solve, please post your logcat. – Machado Nov 20 '14 at 11:50

score 0 · Accepted Answer · answered Nov 20 '14 at 12:02

Ok This is fairly simple but I assume you are new to programming , so what others want you to do can observed from the below code :

package com.example.myfirstapp;

import android.app.Activity;
import android.os.Bundle;
import android.text.TextUtils;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;

    public class MainActivity extends Activity implements View.OnClickListener {

        EditText mFuelCost;
        EditText mDistance;
        EditText mMilesPerGallon;

        Button mBtn1;

        TextView mResult;

        @Override
        public void onCreate(Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);
            setContentView(R.layout.main);

            mFuelCost = (EditText) findViewById(R.id.fuelCost);
            mDistance = (EditText) findViewById(R.id.distance);
            mMilesPerGallon = (EditText) findViewById(R.id.milesPerGallon);

            mBtn1 = (Button) findViewById(R.id.btn_1);

            mResult =(TextView) findViewById(R.id.result);

            mBtn1.setOnClickListener(this);

        }

        @Override
        public void onClick(View v) {
            float num1 = 0;
            float num2 = 0;
            float num3 = 0;

            float result = 0;

            if (TextUtils.isEmpty(mFuelCost.getText().toString())
                    || TextUtils.isEmpty(mDistance.getText().toString())
                    || TextUtils.isEmpty(mMilesPerGallon.getText().toString())) {
                return;
            }

            num1 = Float.parseFloat(mFuelCost.getText().toString());
            num2 = Float.parseFloat(mDistance.getText().toString());
            num3 = Float.parseFloat(mMilesPerGallon.getText().toString());

            switch (v.getId()) {
                case R.id.btn_1:
                    result = ((num1 * 4.5461f) * (num2 / num3)) / 100;
                    break;
                default:
                    break;
            }

            mResult.setText("£" + result);
        }
    }

Thanks I was struggling to change to code without the visuals this is my first project and your help is greatly appreciated. — Rhys Window, Nov 20 '14 at 12:09

When declaring 'public class MainActivity extends Activity implement OnClickListener'

2 Answers2