定义圆角矩形背景

XML文件 res/drawable/my_rounded_rectangle.xml

<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android" >
<solid android:color="#f0600000"/>
<stroke android:width="3dp" android:color="#ffff8080"/>
<corners android:radius="5dp"/>
<padding android:left="10dp"
android:top="10dp"
android:right="10dp"
android:bottom="10dp"/>

</shape>

在Java中使用图像

@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
GradientDrawable roundedRectangle=(GradientDrawable) this.getResources().getDrawable(R.drawable.my_rounded_rectangle);
TextView tv=(TextView)findViewById(R.id.text1);
tv.setBackgroundDrawable(roundedRectangle);
}