安卓：TextView的高度缩小字体大小后，不会改变

当我按一下按钮，字体大小缩小到12。 然而，结果是：

When I click on the button, the font size shrinks to 12. However, the result is :

main.xml中

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:orientation="vertical" >

    <TextView
        android:id="@+id/test"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:textSize="40sp"
        android:background="#80ff0000"
        android:text="@string/hello" />

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

</LinearLayout>

Java的：

java:

public class FontSizeTestActivity extends Activity {
    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        final TextView text = (TextView) findViewById(R.id.test);




        Button button1 = (Button) findViewById(R.id.button1);
        button1.setOnClickListener(new View.OnClickListener() {

            public void onClick(View v) {

                text.setTextSize(12);
            }
        });
    }
}

我如何缩小的TextView的高度，使其只包装的实际字体？

How do I shrink the height of the textView so that it only wraps the actual font?