Android中同一个ImageView中根据状态显示不同图片

if(条件1) {  
     image.setBackground(R.id.xxx1);  
} else if (条件2) {  
     image.setBackground(R.id.xxx2);  
} 

<level-list xmlns:android="http://schemas.android.com/apk/res/android"> 
     <item android:maxLevel="4"  android:drawable="@drawable/stat_sys_battery_0" /> 
     <item android:maxLevel="14"  android:drawable="@drawable/stat_sys_battery_10" /> 
     <item android:maxLevel="29" android:drawable="@drawable/stat_sys_battery_20" /> 
     <item android:maxLevel="49" android:drawable="@drawable/stat_sys_battery_40" /> 
     <item android:maxLevel="69"  android:drawable="@drawable/stat_sys_battery_60" /> 
     <item android:maxLevel="89" android:drawable="@drawable/stat_sys_battery_80" /> 
     <item android:maxLevel="100" android:drawable="@drawable/stat_sys_battery_100" /> 
</level-list> 

imageview.getDrawable().setLevel(50);