Android : Android Studio Unfortunately, application has stopped

So I have been trying hard to fix the problem. Seems like my Application (Proffesor's Application) fails to run when I'm on the YearAndSection Java file going to activity_content. What is supposed to be the problem? The application stops everytime I press OK button on the checklist. I'm kind of new on android studio so please do help me. Thanks.

package com.example.user.professorsapplication;

import android.app.AlertDialog;
import android.content.DialogInterface;
import android.content.Intent;
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.ArrayAdapter;
import android.widget.Button;
import android.widget.EditText;
import android.widget.ListView;
import android.widget.TextView;
import android.widget.Toast;

import java.util.ArrayList;


public class YearAndSection extends ActionBarActivity {
    TextView addYear;
    Button yearSec;



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

        yearSec = (Button) findViewById(R.id.btnYear);
        addYear = (TextView) findViewById(R.id.txtYearSec);
        yearSec.setOnClickListener(new View.OnClickListener(){
            @Override
            public void onClick(View view) {
                AlertDialog.Builder builder = new AlertDialog.Builder(YearAndSection.this);
                final EditText txtYearSec = new EditText(YearAndSection.this);


                //process
                builder.setTitle("Year and Section");
                builder.setMessage("Enter Year and Section");
                builder.setView(txtYearSec);
                builder.setPositiveButton("OK", new DialogInterface.OnClickListener() {
                    @Override
                    public void onClick(DialogInterface dialog, int which)
                    {
                        addYear.setText(txtYearSec.getText());
                        Display();
                        Toast.makeText(getApplicationContext(), "Course has been named", Toast.LENGTH_SHORT);


                    }
                });

                builder.setNegativeButton("Cancel", new DialogInterface.OnClickListener() {
                    @Override
                    public void onClick(DialogInterface dialog, int which)
                    {
                        Toast.makeText(getApplicationContext(), "Course has not been named", Toast.LENGTH_SHORT);
                    }
                });

                AlertDialog dialog = builder.create();
                dialog.show();

            }
            public void Display() { }
        });


        final ArrayList array = new ArrayList();
        final String[] strings = {"Attendance","Assignment","Exams","Chapter Test","Reports","LabWork","Projects","Midterms","FinalGrade"};

        addYear.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                AlertDialog.Builder alert = new  AlertDialog.Builder(YearAndSection.this);
                alert.setTitle("Select Category");
                alert.setMultiChoiceItems(strings, null, new  DialogInterface.OnMultiChoiceClickListener() {
                    @Override
                    public void onClick(DialogInterface dialog, int which, boolean isChecked) {
                        if (isChecked)
                        {
                            array.add(which);
                        }
                        else if (array.contains (which)){
                            array.remove(Integer.valueOf(which));
                        }
                    }
                });
                alert.setPositiveButton("Ok", new  DialogInterface.OnClickListener() {
                    @Override
                    public void onClick(DialogInterface dialog, int which) {
                        for (int intloop = 0; intloop < array.size(); intloop++) {
                            array.get(intloop);
                            ArrayAdapter<String> adapt = new ArrayAdapter<String>(YearAndSection.this, R.layout.list, array);
                            ListView list = (ListView)             findViewById(R.id.list);
                            list.setAdapter(adapt);
                        }
                        Display();
                        Toast.makeText(getApplicationContext(),"Done",        Toast.LENGTH_SHORT).show();

                    }

                });
                AlertDialog poop = alert.create();
                poop.show();
            }
            public void Display() { }
        });
        Button button = (Button) findViewById(R.id.BtnMove);

        button.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                startActivity(new Intent(YearAndSection.this, Content.class));
            }
        });
    }




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

        //noinspection SimplifiableIfStatement
        if (id == R.id.action_settings) {
            return true;
        }

        return super.onOptionsItemSelected(item);
     }
}

This is for the layout of the activity_content.xml

 <LinearLayout
       xmlns:android="http://schemas.android.com/apk/res/android"
       xmlns:tools="http://schemas.android.com/tools"
       android:layout_width="match_parent"
       android:layout_height="match_parent"
       android:paddingLeft="@dimen/activity_horizontal_margin"
       android:paddingRight="@dimen/activity_horizontal_margin"
       android:paddingTop="@dimen/activity_vertical_margin"
       android:paddingBottom="@dimen/activity_vertical_margin"
       tools:context="com.example.user.professorsapplication.Content"
       android:orientation="horizontal">
    <ListView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:id="@+id/list" />
</LinearLayout>

This is for the list.xml

<TextView
        xmlns:android="http://schemas.android.com/apk/res/android"
       android:orientation="vertical"
       android:layout_width="match_parent"
       android:layout_height="match_parent">
</TextView>