TextView加边框

package samples.test; 
public class MyTextView extends TextView { 
    public MyTextView(Context context, AttributeSet attrs, int defStyle) { 
        super(context, attrs, defStyle); 
    } 
 
    public MyTextView(Context context, AttributeSet attrs) { 
        super(context, attrs); 
    } 
 
    public MyTextView(Context context) { 
        super(context); 
    } 
 
    @Override 
    protected void onDraw(Canvas canvas) { 
        super.onDraw(canvas); 
        Rect rect = new Rect(); 
        Paint paint = new Paint(); 
        paint.setStyle(Paint.Style.STROKE); 
        paint.setColor(Color.WHITE); 
        paint.setStrokeWidth(3); 
        getLocalVisibleRect(rect); 
        canvas.drawRect(rect, paint);        
    } 
}  
<?xml version="1.0" encoding="utf-8"?> 
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" 
    android:orientation="vertical" android:layout_width="fill_parent" 
    android:layout_height="fill_parent"> 
    <samples.test.MyTextView android:layout_width="fill_parent" 
        android:layout_height="wrap_content" android:text="@string/hello" /> 
</LinearLayout>