应用程序在启动新活动(点击按钮)时不断崩溃

Question

应用程序在启动新活动时不断崩溃。主活动启动后，我按下任何按钮，应用程序就会停止或崩溃。

我不知道我可能做得不对，但这是我的mainActivity代码
我正在使用安卓工作室

public class Calculator  extends ActionBarActivity{
    public Button loan;
    public Button exit;

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.calc);
        addListenerOnButton();
    }
    public void addListenerOnButton() {
        final Context context = this;
        loan = (Button) findViewById(R.id.loans);
        loan.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View arg0) {
            Intent intent = new Intent(context, loancalculator.class);
            startActivity(intent);
            finish();

            }
        });
        exit = (Button) findViewById(R.id.exits);
        exit.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View arg0) {
                Intent intent = new Intent(context, presentvaluecalculator.class);
                startActivity(intent);
                finish();

            }
        });
    }
}

Answer 1

        public class Calculator  extends ActionBarActivity{
            public Button loan,exit;
            Calculator context;

            @Override
            public void onCreate(Bundle savedInstanceState) {
                super.onCreate(savedInstanceState);
                setContentView(R.layout.calc);
                context = this;
                addListenerOnButton();
            }
            public void addListenerOnButton() {

                loan = (Button) findViewById(R.id.loans);
                loan.setOnClickListener(new View.OnClickListener() {
                    @Override
                    public void onClick(View arg0) {
                    Intent intent = new Intent(context, loancalculator.class);
                    startActivity(intent);
                    finish();

                    }
                });
                exit = (Button) findViewById(R.id.exits);
                exit.setOnClickListener(new View.OnClickListener() {
                    @Override
                    public void onClick(View arg0) {
                        Intent intent = new Intent(context, presentvaluecalculator.class);
                        startActivity(intent);
                        finish();

                    }
                });
            }
        }

   // And make sure you have declared all the activities in manifest
        <activity android:name="com.yourpackage.loancalculator"/>
        <activity  android:name="com.yourpackage.presentvaluecalculator"/>