Android 如何获取当前电池百分比？

我正在创建一个电池监视器应用程序，并试图显示当前的电池百分比。我有一个广播接收器，正在收听

<action android:name="android.intent.action.BATTERY_CHANGED" />

出于某种原因，结果总是当前电池电量：1.0%…我哪里出了问题

编辑：

收件人在舱单中注册为

<receiver android:name=".PowerMonitorReceiver">
    <intent-filter>
        <action android:name="android.intent.action.ACTION_POWER_CONNECTED" />
        <action android:name="android.intent.action.ACTION_POWER_DISCONNECTED" />
        <action android:name="android.intent.action.BATTERY_LOW" />
        <action android:name="android.intent.action.BATTERY_OKAY" />
        <action android:name="android.intent.action.BATTERY_CHANGED" />
    </intent-filter>
</receiver>

---

由于您正在收听多个广播，因此需要确定它是哪种类型的广播

String action = intent.getAction();

if(action.equals(Intent.ACTION_BATTERY_CHANGED)){
    int level   = intent.getIntExtra(BatteryManager.EXTRA_LEVEL, 0);
    int scale   = intent.getIntExtra(BatteryManager.EXTRA_SCALE, 100);
    int percent = (level*100)/scale;

    Toast.makeText(context, "Current battery level: " + percent + "%", Toast.LENGTH_SHORT).show();
}

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我认为已经很晚了，但解决办法很简单。根据，如果您已在xml中注册广播接收器，则不会收到已更改电池的更新，因为它是粘性广播

您需要在java程序中注册Broadcastreceivers，如下所示

IntentFilter ifilter = new IntentFilter(Intent.ACTION_BATTERY_CHANGED);
Intent batteryStatus = context.registerReceiver(null, ifilter);

int level = batteryStatus.getIntExtra(BatteryManager.EXTRA_LEVEL, -1);
int scale = batteryStatus.getIntExtra(BatteryManager.EXTRA_SCALE, -1);
float batteryPct = (level * 100) / (float)scale;

注意：即使将null作为接收器传递，您仍然可以接收所有必需的电池数据。您还可以传递一个Receiver类而不是null来进行连续监视，但请注意，这会耗尽设备的电池，因为这些广播经常被抛出

boolean acCharge = false;
IntentFilter ifilter = new IntentFilter(Intent.ACTION_BATTERY_CHANGED);
Intent batteryStatus = registerReceiver(null, ifilter);
int status = batteryStatus.getIntExtra(BatteryManager.EXTRA_STATUS, -1);
boolean isCharging = status == BatteryManager.BATTERY_STATUS_CHARGING ||
        status == BatteryManager.BATTERY_STATUS_FULL;

if(isCharging){
        chargePercentage = 
        batteryStatus.getIntExtra(BatteryManager.EXTRA_LEVEL, -1);
    }

---

chargePercentage变量将为您提供当前的收费百分比。

将您的收件人和您注册的地址发送出去，这肯定会有所帮助。这将触发并适用于所有其他触发器。但换过的电池从未被调用过。我已经在物理设备和Genymotion模拟器上用电池模拟了不同的事件。

IntentFilter ifilter = new IntentFilter(Intent.ACTION_BATTERY_CHANGED);
Intent batteryStatus = context.registerReceiver(null, ifilter);

int level = batteryStatus.getIntExtra(BatteryManager.EXTRA_LEVEL, -1);
int scale = batteryStatus.getIntExtra(BatteryManager.EXTRA_SCALE, -1);
float batteryPct = (level * 100) / (float)scale;

boolean acCharge = false;
IntentFilter ifilter = new IntentFilter(Intent.ACTION_BATTERY_CHANGED);
Intent batteryStatus = registerReceiver(null, ifilter);
int status = batteryStatus.getIntExtra(BatteryManager.EXTRA_STATUS, -1);
boolean isCharging = status == BatteryManager.BATTERY_STATUS_CHARGING ||
        status == BatteryManager.BATTERY_STATUS_FULL;

if(isCharging){
        chargePercentage = 
        batteryStatus.getIntExtra(BatteryManager.EXTRA_LEVEL, -1);
    }