((TextView)findViewById(R.id.text)).setText(Html.fromHtml("X²")); 

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>

回家休息了20多天 嘿嘿今天看见别人做了一个右上角图标的东西，感觉不错 本以为是用.9.png格式实现的原来不是

仔细看了一下原来如下：

<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
        android:layout_width="fill_parent"
        android:layout_height="fill_parent">
 
        <Button android:id="@+id/discounts_button"
                android:layout_width="wrap_content" 
                android:layout_height="wrap_content" 
               
                android:text="我要进行测试"
                android:textColor="#FFFFFF"
                android:textSize="20sp"
               
                android:layout_marginTop="40dp"
                android:layout_marginLeft="20dp"/>
 
        <RelativeLayout android:layout_width="wrap_content" 
                android:layout_height="wrap_content"
                android:layout_gravity="top|left">
 
            <ImageView android:layout_width="wrap_content" 
                    android:layout_height="wrap_content"
                    android:adjustViewBounds="true"
                    android:src="/blog_article/@drawable/a1/index.html"
                    android:layout_centerInParent="true"/>
 
             <TextView android:layout_width="wrap_content" 
                           android:layout_height="wrap_content"
                           android:text
                           android:text="20"
                           android:layout_centerInParent="true" />
         </RelativeLayout>
</FrameLayout>