获取Android设备电池电量状态

Android开发者可以利用BroadcastReceiver机制，获取电池电量变化的ACTION_BATTERY_CHANGED intent，进而获取当前android设备的电池状态。

具体操作步骤：

1. 创建一个监听ACTION_BATTERY_CHANGED事件的intentFilter。

2. 创建一个BroadcastReceiver对象，该对象可以接收broadcast intent。

3. 注册BroadcastReceiver对象来监听ACTION_BATTERY_CHANGED事件。

4. 在BroadcastReceiver对象中，重写onReceive方法，在onReceive方法的传入参数intent里获取需要的电池状态信息。

5. 在生命周期结束时，取消step4中的注册。

[java]view
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public class BatteryMonitorActivity extends Activity {

private TextView batterLevel;

private BroadcastReceiver batteryLevelRcvr;

private IntentFilter batteryLevelFilter;

@Override

public void onCreate(Bundle savedInstanceState) {

super.onCreate(savedInstanceState);

setContentView(R.layout.main);

batterLevel = (TextView) findViewById(R.id.batteryLevel);

monitorBatteryState();

}

@Override

protected void onDestroy() {

super.onDestroy();

unregisterReceiver(batteryLevelRcvr);

}

private void monitorBatteryState() {

batteryLevelRcvr = new BroadcastReceiver() {

public void onReceive(Context context, Intent intent) {

StringBuilder sb = new StringBuilder();

int rawlevel = intent.getIntExtra("level", -1);

int scale = intent.getIntExtra("scale", -1);

int status = intent.getIntExtra("status", -1);

int health = intent.getIntExtra("health", -1);

int level = -1; // percentage, or -1 for unknown

if (rawlevel >= 0 && scale > 0) {

level = (rawlevel * 100) / scale;

}

sb.append("The phone");

if (BatteryManager.BATTERY_HEALTH_OVERHEAT == health) {

sb.append("'s battery feels very hot!");

} else {

switch (status) {

case BatteryManager.BATTERY_STATUS_UNKNOWN:

sb.append("no battery.");

break;

case BatteryManager.BATTERY_STATUS_CHARGING:

sb.append("'s battery");

if (level <= 33)

sb.append(" is charging, battery level is low"

+ "[" + level + "]");

else if (level <= 84)

sb.append(" is charging." + "[" + level + "]");

else

sb.append(" will be fully charged.");

break;

case BatteryManager.BATTERY_STATUS_DISCHARGING:

case BatteryManager.BATTERY_STATUS_NOT_CHARGING:

if (level == 0)

sb.append(" needs charging right away.");

else if (level > 0 && level <= 33)

sb.append(" is about ready to be recharged, battery level is low"

+ "[" + level + "]");

else

sb.append("'s battery level is" + "[" + level + "]");

break;

case BatteryManager.BATTERY_STATUS_FULL:

sb.append(" is fully charged.");

break;

default:

sb.append("'s battery is indescribable!");

break;

}

}

sb.append(' ');

batterLevel.setText(sb.toString());

}

};

batteryLevelFilter = new IntentFilter(Intent.ACTION_BATTERY_CHANGED);

registerReceiver(batteryLevelRcvr, batteryLevelFilter);

}

}

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<?xml version="1.0" encoding="utf-8"?>

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"

android:layout_width="fill_parent"

android:layout_height="fill_parent"

android:orientation="vertical" >

<TextView

android:id="@+id/batteryLevel"

android:layout_width="fill_parent"

android:layout_height="fill_parent"

android:gravity="center_vertical|center_horizontal"

android:textSize="50dip">

</TextView>

</LinearLayout>

Android的上层实现显示手机电池电量是通过监听实现，当电池电量改变时会通知到程序。

当然这个有朋友就要问了我不是想监听电池电量，我是想直接获取当前的电池电量。

其实这是同一个问题，当你在初始化监听器的时候他会自动首先获取电池的电量信息，然后后续当电池改变时同时也会通知当前电池电量的改变情况。

转自

http://www.blogjava.net/zhangqian1216/archive/2012/01/04/367858.html

http://blog.macrowen.com/Technology/3074.html