多个标记错误会阻止项目在模拟器中运行吗？

Question

此行有多个标记

  

  
• 覆盖android.support.v7.app.ActionBarActivity.onCreate
  
• 观察点：MainActivity [访问和修改] - button2
  

不一定是错误，但我的应用程序不会在模拟器中运行，我不知道为什么。这可能是原因吗？

这是我的主要

    package ie.gmit.project;

    import android.support.v7.app.ActionBarActivity;
    import android.support.v7.app.ActionBar;
    import android.support.v4.app.Fragment;
    import android.content.Intent;
    import android.net.Uri;
    import android.os.Bundle;
    import android.view.LayoutInflater;
    import android.view.Menu;
    import android.view.MenuItem;
    import android.view.View;
    import android.view.ViewGroup;
    import android.widget.Button;
    import android.os.Build;

    public class MainActivity extends ActionBarActivity  {


    private Button button2;//this is a bad name

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

        button2= (Button) findViewById(R.id.button2);//find the button


        button2.setOnClickListener(new View.OnClickListener() {

            @Override
            public void onClick(View v) {
               Intent i = new Intent(v.getContext(), IntroActivity.class);
               startActivity(i);
               // finish();//if you want to close main activity after start info activity
        }});

        if (savedInstanceState == null) {
            getSupportFragmentManager().beginTransaction()
                    .add(R.id.container, new PlaceholderFragment())
                    .commit();
        }


    }

    public void openSite(View v){
        Uri uri = Uri.parse("http://gmitsu.ie/clubssocs/directory.html");
        Intent intent = new Intent(Intent.ACTION_VIEW, uri);
        startActivity(intent);
    }


    @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);
    }

    /**
     * A placeholder fragment containing a simple view.
     */
    public static class PlaceholderFragment extends Fragment {

        public PlaceholderFragment() {
        }

        @Override
        public View onCreateView(LayoutInflater inflater, ViewGroup container,
                Bundle savedInstanceState) {
            View rootView = inflater.inflate(R.layout.fragment_main, container, false);
            return rootView;
        }
    }




}