android BatteryManager电池管理

首先要说的是，电池管理不是电源管理。算然电源是由电池供给的，但是在逻辑管理中，怎么供电的，和怎么用电的，这两个是分开的。

java代码： 
frameworks/frameworks/base/services/java/com/android/server/Ba 
tteryService.java 
监听Uevent、读取sysfs里中的状态 。
JNI代码： 
frameworks/base/services/jni/com_android_server_BatteryService. 
cpp 
kernel driver代码 
drivers/power/xx_battery.c 

获得电池信息的两种方式(可以3种)：

Android.content.BroadcastReceiver类
广播Intent.ACTION_BATTERY_CHANGED

Android.os.BatteryManager类

1.使用广播接收器：

   ●(1) 电池信息的取得，调用registerReceiver()方法。
         第1个参数，设置BroadcastReceiver实例
第2个参数，设置追加了Intent.ACTION_BATTERY_CHANGED处理的IntentFilter实例。

    ●(2) 在BroadcastReceiver的onReceive()事件，接收到的Intent.ACTION_BATTERY_CHANGED，包括下面的信息。
    “status”（int类型）…状态，定义值是BatteryManager.BATTERY_STATUS_XXX。
    “health”（int类型）…健康，定义值是BatteryManager.BATTERY_HEALTH_XXX。
    “present”（boolean类型）
    “level”（int类型）…电池剩余容量
    “scale”（int类型）…电池最大值。通常为100。
    “icon-small”（int类型）…图标ID。
    “plugged”（int类型）…连接的电源插座，定义值是BatteryManager.BATTERY_PLUGGED_XXX。
    “voltage”（int类型）…mV。
    “temperature”（int类型）…温度，0.1度单位。例如 表示197的时候，意思为19.7度。 
    “technology”（String类型）…电池类型，例如，Li-ion等等。

2.获取系统服务的方式：

Constants
int	BATTERY_HEALTH_COLD
int	BATTERY_HEALTH_DEAD
int	BATTERY_HEALTH_GOOD
int	BATTERY_HEALTH_OVERHEAT
int	BATTERY_HEALTH_OVER_VOLTAGE
int	BATTERY_HEALTH_UNKNOWN
int	BATTERY_HEALTH_UNSPECIFIED_FAILURE
int	BATTERY_PLUGGED_AC	Power source is an AC charger.
int	BATTERY_PLUGGED_USB	Power source is a USB port.
int	BATTERY_PLUGGED_WIRELESS	Power source is wireless.
int	BATTERY_STATUS_CHARGING
int	BATTERY_STATUS_DISCHARGING
int	BATTERY_STATUS_FULL
int	BATTERY_STATUS_NOT_CHARGING
int	BATTERY_STATUS_UNKNOWN
String	EXTRA_HEALTH	Extra for ACTION_BATTERY_CHANGED: integer containing the current health constant.
String	EXTRA_ICON_SMALL	Extra for ACTION_BATTERY_CHANGED: integer containing the resource ID of a small status bar icon indicating the current battery state.
String	EXTRA_LEVEL	Extra for ACTION_BATTERY_CHANGED: integer field containing the current battery level, from 0 to EXTRA_SCALE.
String	EXTRA_PLUGGED	Extra for ACTION_BATTERY_CHANGED: integer indicating whether the device is plugged in to a power source; 0 means it is on battery, other constants are different types of power sources.
String	EXTRA_PRESENT	Extra for ACTION_BATTERY_CHANGED: boolean indicating whether a battery is present.
String	EXTRA_SCALE	Extra for ACTION_BATTERY_CHANGED: integer containing the maximum battery level.
String	EXTRA_STATUS	Extra for ACTION_BATTERY_CHANGED: integer containing the current status constant.
String	EXTRA_TECHNOLOGY	Extra for ACTION_BATTERY_CHANGED: String describing the technology of the current battery.
String	EXTRA_TEMPERATURE	Extra for ACTION_BATTERY_CHANGED: integer containing the current battery temperature.
String	EXTRA_VOLTAGE	Extra for ACTION_BATTERY_CHANGED: integer containing the current battery voltage level.