android获得手机的电量
在android中，要获得手机的电量的话，可以通过intent广播去实现，监听
action_battery_changed，例子如下：

package com.liao;import android.app.Activity;import android.content.BroadcastReceiver;import android.content.Context;import android.content.Intent;import android.content.IntentFilter;import android.os.Bundle;import android.widget.TextView;public class BatteryLevelActivity extends Activity {    /** Called when the activity is first created. */    private TextView batterLevel;    @Override    /**     * Called when the current activity is first created.     */    public void onCreate(Bundle icicle) {        super.onCreate(icicle);        setContentView(R.layout.main);        batterLevel = (TextView) this.findViewById(R.id.batteryLevel);        batteryLevel();    }      private void batteryLevel() {        BroadcastReceiver batteryLevelReceiver = new BroadcastReceiver() {            public void onReceive(Context context, Intent intent) {                context.unregisterReceiver(this);                int rawlevel = intent.getIntExtra("level", -1);//获得当前电量                int scale = intent.getIntExtra("scale", -1);//获得总电量                int level = -1;                if (rawlevel >= 0 && scale > 0) {                    level = (rawlevel * 100) / scale;                }                batterLevel.setText("Battery Level Remaining: " + level + "%");            }        };        IntentFilter batteryLevelFilter = new IntentFilter(Intent.ACTION_BATTERY_CHANGED);        registerReceiver(batteryLevelReceiver, batteryLevelFilter);    }    }

如果是2。0后的SDK，也可以这样：
public void onReceive(Context context, Intent intent) {

context.unregisterReceiver(this);

int rawlevel = intent.getIntExtra(BatteryManager.EXTRA_LEVEL, -1);

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

就是修改一下类而已