为Android手机充电时检测当前消耗的电流

Question

I would like to develop a small app that shows the current current being drawn by the phone during a charge. eg The phone is plugged in via A/C and is pulling 1A.

From my research there are the existing APIs:

http://developer.android.com/reference/android/os/BatteryManager.html http://developer.android.com/training/monitoring-device-state/battery-monitoring.html

However these will only tell you whether it is charging via USB or A/C and it's current status.

I would like to do some tests to view the charge rate with different cables and A/C adaptors.

Answer 1

You can use the following method to check battery level

    private static int checkBatteryLevel(Context context) {
        IntentFilter ifilter = new IntentFilter(Intent.ACTION_BATTERY_CHANGED);
        Intent batteryStatus = context.registerReceiver(null, ifilter);

        // Are we charging / charged?
        int status = batteryStatus.getIntExtra(BatteryManager.EXTRA_STATUS, -1);
        boolean isCharging = status == BatteryManager.BATTERY_STATUS_CHARGING || status == BatteryManager.BATTERY_STATUS_FULL;

        // If the device is charging then set the state as charging and return.
        if (isCharging)
            return 100;

        // Get the battery level.
        int level = batteryStatus.getIntExtra(BatteryManager.EXTRA_LEVEL, -1);
        int scale = batteryStatus.getIntExtra(BatteryManager.EXTRA_SCALE, -1);

        // To get the battery level in %
        int batteryLevel = (level * 100) / scale;
        Log.e(Constants.TAG, "Battery Level: " + batteryLevel);

        return batteryLevel;
    }

And you can use the following receiver to detect getting connected and disconnected

public class BatteryInformationReceiver extends BroadcastReceiver {

    private static final String ACTION_POWER_CONNECTED = "android.intent.action.ACTION_POWER_CONNECTED";
    private static final String ACTION_POWER_DISCONNECTED = "android.intent.action.ACTION_POWER_DISCONNECTED";

    @Override
    public void onReceive(Context context, Intent intent) {

        String intentAction = intent.getAction();
        if (intentAction.equalsIgnoreCase(ACTION_POWER_CONNECTED)) {

        } else if (intentAction.equalsIgnoreCase(ACTION_POWER_DISCONNECTED)) {

        } 

    }
}

and in manifest

<receiver android:name="your.package.receivers.BatteryInformationReceiver" >
            <intent-filter>
                <action android:name="android.intent.action.ACTION_POWER_CONNECTED" />
                <action android:name="android.intent.action.ACTION_POWER_DISCONNECTED" />
            </intent-filter>
        </receiver>

and then, on getting connected, calculate the battery level using the above method. and after getting disconnected, calculate the battery level. and from the difference between times and value of battery. you can calculate whatever you want.

Hope this helps