Button pressed and change textview color

Question

Can anyone see what is wrong with my code :( I can't even create a simple app, it keep crashing it.

What the app is going to do is when user press the button the textview will change colour to RED.

public class MainActivity extends Activity {

public TextView tv1;
public Button bt1;

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

    bt1 = (Button)findViewById(R.id.button1);
    tv1 = (Button)findViewById(R.id.textView1);

    bt1.setOnClickListener(new View.OnClickListener() {

        @Override
        public void onClick(View v) {
            // TODO Auto-generated method stub
            tv1.setTextColor(Color.BLACK);
        }
    });

}

<RelativeLayout 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"
tools:context=".MainActivity" >

<Button
    android:id="@+id/button1"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_alignParentLeft="true"
    android:layout_alignParentTop="true"
    android:text="Button" />

<TextView
    android:id="@+id/textView1"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_alignBottom="@+id/button1"
    android:layout_toRightOf="@+id/button1"
    android:text="TextView" />

Answer 1

tv1 = (Button)findViewById(R.id.textView1);

用。。。来代替

tv1 = (TextView)findViewById(R.id.textView1);