如何以固定间隔获取电池电流？

Question

我想每隔 5 秒获取一次电池电流和电压。

但在我的来源中，电压和电流以随机间隔变化。

比如5秒、10秒、9秒、.......

听说 BroadcastReceiver 要求 10 秒内返回值。

我猜这是一个原因，但我不知道如何解决这个问题。

package com.example.hubertlee.batterywearrate;

import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.content.IntentFilter;
import android.os.BatteryManager;
import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.widget.TextView;

public class MainActivity extends AppCompatActivity {
  private TextView batteryInfo;
  Long avgCurrent = null, currentNow = null;
  int count = 0;
  float power = 0;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

    BatteryManager mBatteryManager = (BatteryManager) getSystemService(Context.BATTERY_SERVICE);
    batteryInfo = (TextView) findViewById(R.id.textViewBatteryInfo);
    this.registerReceiver(this.batteryinfoReceiver, new IntentFilter(Intent.ACTION_BATTERY_CHANGED));

    if (android.os.Build.VERSION.SDK_INT >= android.os.Build.VERSION_CODES.LOLLIPOP) {
        avgCurrent = mBatteryManager.getLongProperty(BatteryManager.BATTERY_PROPERTY_CURRENT_AVERAGE);
        currentNow = mBatteryManager.getLongProperty(BatteryManager.BATTERY_PROPERTY_CURRENT_NOW);
    }

}



private BroadcastReceiver batteryinfoReceiver = new BroadcastReceiver(){
    public void onReceive(Context context, Intent intent){

        int health = intent.getIntExtra(BatteryManager.EXTRA_HEALTH, 0);
        int icon_small = intent.getIntExtra(BatteryManager.EXTRA_ICON_SMALL,0);
        int level = intent.getIntExtra(BatteryManager.EXTRA_LEVEL, 0);
        int plugged = intent.getIntExtra(BatteryManager.EXTRA_PLUGGED, 0);
        boolean present = intent.getExtras().getBoolean(BatteryManager.EXTRA_PRESENT);
        int scale = intent.getIntExtra(BatteryManager.EXTRA_SCALE, 0);
        int status = intent.getIntExtra(BatteryManager.EXTRA_STATUS, 0);
        String technology = intent.getExtras().getString(BatteryManager.EXTRA_TECHNOLOGY);
        float temp = intent.getIntExtra(BatteryManager.EXTRA_TEMPERATURE, 0);
        float voltage = intent.getIntExtra(BatteryManager.EXTRA_VOLTAGE, 0);
        batteryInfo.setText("Health: " + health + "\n" + "Icon small : "+icon_small+"\n" +
                "Level : "+level+"\n"+"Present : "+present+"\n"+"Scale: "+
                scale+"\n"+"Status :"+status+"\n"+ "Technology:"+technology+"\n"+
                "Temperature :"+temp/10+"'C\n"+"Voltage:"+voltage/1000+"V\n"+"BATTERY_PROPERTY_CURRENT_AVERAGE = "
                + avgCurrent + "mAh"+"\n"+"BATTERY_PROPERTY_CURRENT_NOW =  " + currentNow + "mAh"+"\n"+"count ="+count);
        count++;




    }
  };
}

Answer 1

如果您想让代码以固定间隔运行，请查看警报管理器： https://developer.android.com/reference/android/app/AlarmManager.html

就像 Selvin 所说，广播只有在发生变化时才会被调用。