如何檢測充電記錄的電池電量和狀態？

Question

我正嘗試在android中爲電池充電日誌，它工作正常。但問題是我無法檢測電池電量以及充電器的狀態。爲了您的信息，我是使用android的初學者，希望有人可以幫助我處理代碼。

public class ListViewA extends Activity { 
/**Called when the activity is first created.*/ 
@Override 
protected void onCreate(Bundle savedInstanceState) { 
    super.onCreate(savedInstanceState); 
    setContentView(R.layout.listview); 
    ListView lv= (ListView)findViewById(R.id.listview); 

    // create the grid item mapping 
    String[] from = new String[] {"col_1", "col_2", "col_3", "col_4"}; 
    int[] to = new int[] { R.id.item2, R.id.item3, R.id.item4, R.id.item5}; 

    // prepare the list of all records 
    List<HashMap<String, String>> fillMaps = new ArrayList<HashMap<String, String>>();   

    DateFormat dateFormat = new SimpleDateFormat("yyyy/MM/dd HH:mm"); 
    //get current date time with Calendar() 
    Calendar cal = Calendar.getInstance(); 

     BroadcastReceiver batteryLevelReceiver = new BroadcastReceiver() { 
      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); 
      int level = -1; 
      if (rawlevel >= 0 && scale > 0) { 
       level = (rawlevel * 100)/scale; 
      } 

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

      String strStatus = ""; 
      switch (status) { 
       case BatteryManager.BATTERY_STATUS_UNKNOWN: 
        strStatus= "Unknown Charged"; 
        break; 
       case BatteryManager.BATTERY_STATUS_CHARGING: 
        strStatus = "Charged Plugged"; 
        break; 
       case BatteryManager.BATTERY_STATUS_DISCHARGING: 
        strStatus = "Charged Unplugged"; 
        break; 
       case BatteryManager.BATTERY_STATUS_NOT_CHARGING: 
        strStatus = "Not Charging"; 
        break; 
       case BatteryManager.BATTERY_STATUS_FULL: 
        strStatus = "Charged Completed"; 
        break; 
      } 
     } 
    }; 


     HashMap<String, String> map = new HashMap<String, String>(); 
     map.put("col_1", DateFormat(cal.getTime())); 
     int level = -1;   
     map.put("col_3", Integer.toString(level) + "%"); 
     String strStatus = ""; 
     map.put("col_4", strStatus); 
     fillMaps.add(map); 

    // fill in the grid_item layout 
    SimpleAdapter adapter = new SimpleAdapter(this, fillMaps, R.layout.grid_item, from, to); 
    lv.setAdapter(adapter); 
} 

    private String DateFormat(Date time) { 
    DateFormat dateFormat = new SimpleDateFormat("yyyy/MM/dd   HH:mm"); 
    //get current date time with Calendar() 
    Calendar cal = Calendar.getInstance(); 
    return dateFormat.format(cal.getTime());  
    } 


    } 

Answer 1

private int getBatteryLevel(Context context) { 
    int batteryPercentage = 0; 
    try { 
     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); 

     int status = batteryStatus.getIntExtra(BatteryManager.EXTRA_STATUS, 
       -1); 

     float batteryPct = level/(float) scale; 

     batteryPercentage = (int) (batteryPct * 100); 

     if (batteryPercentage < 0) { 
      batteryPercentage = 0; 

     } 

     Log.d(TAG, "Battery level remaining " + batteryPercentage); 

     String strStatus = ""; 
     switch (status) { 
     case BatteryManager.BATTERY_STATUS_UNKNOWN: 
      strStatus = "Unknown Charged"; 
      break; 
     case BatteryManager.BATTERY_STATUS_CHARGING: 
      strStatus = "Charged Plugged"; 
      break; 
     case BatteryManager.BATTERY_STATUS_DISCHARGING: 
      strStatus = "Charged Unplugged"; 
      break; 
     case BatteryManager.BATTERY_STATUS_NOT_CHARGING: 
      strStatus = "Not Charging"; 
      break; 
     case BatteryManager.BATTERY_STATUS_FULL: 
      strStatus = "Charged Completed"; 
      break; 
     } 

     Log.d(TAG, "battery status " + strStatus); 

    } catch (Exception e) { 
     e.printStackTrace(); 

    } 

    return batteryPercentage; 
}