Develop Reference

How to get battery current at an fixed interval?

I want to get battery Current, and Voltage at an interval of 5 seconds.
But in my source, the Voltage and Current changes at an random interval.
such as 5 seconds, 10 seconds, 9 seconds, .......
I heard BroadcastReceiver requires a return value within 10 seconds.
I guess this is a cause, but I have no idea how to solve this problem.
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++;
}
};
}

If you want to have a code run at fix interval, take a look at Alarm manager :
https://developer.android.com/reference/android/app/AlarmManager.html
Like Selvin said, the broadcast is called only when it change.

Register broadcast receiver in android

I have register battery low broadcast receiver.
Like this
import com.save.sharedpreference.SharedPreference;
import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.telephony.SmsManager;
import android.widget.Toast;
public class BootReceiver extends BroadcastReceiver {
String user_phone_key = "phone_number";
int last_level = 0;
#Override
public void onReceive(Context context, Intent intent) {
int rlevel = intent.getIntExtra("level", -1);
int scale = intent.getIntExtra("scale", -1);
int level = -1;
if (rlevel >= 0 && scale > 0) {
level = (rlevel * 100) / scale;
}
if (level == 48 && last_level == level + 1) {
SharedPreference save_data = new SharedPreference(
context.getApplicationContext());
String phone = save_data.get_string(user_phone_key, null);
Toast.makeText(context, "Level Decrease", Toast.LENGTH_SHORT)
.show();
try {
SmsManager smsManager = SmsManager.getDefault();
smsManager.sendTextMessage(phone, null,
"Your Battery level is less ", null, null);
} catch (Exception e) {
Toast.makeText(context.getApplicationContext(),
"SMS faild, please try again later!", Toast.LENGTH_LONG)
.show();
e.printStackTrace();
}
}
last_level = level + 1;
}
}
Its working fine but the problem is when my battery level is reach 45% it start sending me sms until battery level change from 45%.
I want that when my battery level is reach 45% it just send me sms only one time and again waiting when battery level is 45%.
Is it possible?
Any help please.

Can you just use a local variable, like this?
public class BootReceiver extends BroadcastReceiver {
String user_phone_key = "phone_number";
int last_level = 0;
#Override
public void onReceive(Context context, Intent intent) {
int rlevel = intent.getIntExtra("level", -1);
int scale = intent.getIntExtra("scale", -1);
int level = -1;
if (rlevel >= 0 && scale > 0) {
level = (rlevel * 100) / scale;
}
if (level == 45 && last_level == 46) {
...
last_level = level;
}
}
I know it's not the most elegant solution, but it should work.
The more "official" solution is to use the ACTION_BATTERY_LOW intent to detect charge decreases, which IIRC only fires once, when the device hits low battery. Is there a reason you need to detect the battery level hitting 45%, in particular?

Create a boolean variable to send message only once.Like-
boolean isMsgSent=false;
and modify if loop as-
if(level==45 && !isMsgSent){
// send Msg
isMsgSent=true;
}
else{
isMsgSent=false;
}
It will send message only once when battery level is 45.

ContentObserver in Android

I have successfully monitor incoming SMS and sent it to database for viewing later. I have read about monitor outgoing sms and I don't really understand how it works. Can someone guide me how to code to monitor outgoing sms by using ContentObserver? I will post all my current codes for incoming sms.need guide from where I should start.
smsReceiver.java
package terima.sms.inbox;
import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.os.Bundle;
import android.telephony.gsm.SmsMessage;
import java.net.*;
import java.io.*;
#SuppressWarnings("deprecation")
public class SmsReceiver extends BroadcastReceiver {
#Override
public void onReceive(Context context, Intent intent) {
Bundle bundle = intent.getExtras();
Object messages[] = (Object[]) bundle.get("pdus");
SmsMessage SMS[] = new SmsMessage[messages.length];
for (int n = 0; n < messages.length; n++) {
SMS[n] = SmsMessage.createFromPdu((byte[]) messages[n]);
}
String member_id = "1";
inbox(SMS[0].getOriginatingAddress(), SMS[0].getMessageBody(), member_id);
}
public static Boolean inbox(String telefon, String message, String member_id){
String mesej = "";
for(int i = 0; i < message.length(); i++)
{
if(message.charAt(i) == ' ' || message.charAt(i) == '+')
{
if(message.charAt(i) == ' ')
mesej += "%20";
else
mesej += "%2B";
}
else
{
mesej += message.charAt(i);
}
}
try
{
URL oracle = new URL("http://192.168.1.111/inbox.php?message=" + mesej + "&telefon=" + telefon + "&member=" + member_id);
BufferedReader in = new BufferedReader(new InputStreamReader(oracle.openStream()));
String fetch, total = "";
while ((fetch = in.readLine()) != null)
total += fetch;
in.close();
if(total.equals("1"))
return true;
return false;
}
catch(Exception e)
{
return false;
}
}
}
thanks in advance.

To catch outgoing SMS you should use a ContentObserver coupled with a ContentResolver. Here is the code I use in the ContentObserver:
public class SmsObserver extends ContentObserver{
int smsCount;
public SmsObserver(Context context) {
super(new Handler());
smsCount = 0;
}
public void onChange(boolean selfChange){
super.onChange(selfChange);
readSms();
}
private void readSms(){
Uri uriSMS = Uri.parse("content://sms");
Cursor cur = context.getContentResolver().query(uriSMS, null, null, null, "_id");
cur.moveToLast();
int id = Integer.parseInt(cur.getString(cur.getColumnIndex("_id")));
if(cur != null && id != smsCount && id>0){
smsCount = id;
int type = Integer.parseInt(cur.getString(cur.getColumnIndex("type")));
if(type == 1){
// handle the received sms
}
else{
// handle the sent sms
}
}
cur.close();
}
}
After that you should create an instance of SmsOberver and register it on "content://sms". It will be triggered more often than when you send or receive a new message, so this is why I have a smsCount field.

Battery Manager not receiving BATTERY_PLUGGED_AC int

I have a battery widget, and for some reason it does not receive the BATTERY_PLIGGED_AC integer when the phone is plugged into AC.
I have another widget for the BATTERY_PLUGGED_USB which works just fine.
I can't see anything wrong with my code:
public void onReceive(Context context, Intent intent) {
status = intent.getIntExtra("status", BatteryManager.BATTERY_STATUS_UNKNOWN);
batterylevel = intent.getIntExtra("level", 0);
updateAppWidget(context);
}
public void updateAppWidget(Context context){
RemoteViews updateViews = new RemoteViews(context.getPackageName(), R.layout.androidbatterywidget_layout);
updateViews.setTextViewText(R.id.textView1, " " + batterylevel + "%");
if (status == BatteryManager.BATTERY_PLUGGED_USB)
updateViews.setImageViewResource(R.id.imageView2, R.drawable.usb);
else if (status == BatteryManager.BATTERY_PLUGGED_AC)
updateViews.setImageViewResource(R.id.imageView2, R.drawable.bolt);
else
updateViews.setImageViewResource(R.id.imageView2, R.drawable.empty);
Hopefully someone will be able to spot what I have done wrong. Thanks!

Figured a way around. Sorry for this post I should have looked at it for a little longer myself. For future reference if people seem to have the same problem, it seems to me that the USB value is bundled with the BatteryManager.BATTERY_STATUS_UNKNOWN, but not the AC. So instead all i did was assign a new private int charging, to the value of the BatteryManager.BATTERY_PLUGGED_AC variable. If this is true (and the device is charging throygh AC), then the value is 1, so I simply replaced my previous if statement with
if (charging == 1)
updateViews.setImageViewResource(R.id.imageView2, R.drawable.bolt);
Now the code reads;
private int batterylevel = 0;
private int status;
private int charging;
private BroadcastReceiver myReceiver = new BroadcastReceiver()
{
public void onReceive(Context context, Intent intent)
{
status = intent.getIntExtra("status", BatteryManager.BATTERY_HEALTH_UNKNOWN);
charging = intent.getIntExtra("plugged", BatteryManager.BATTERY_PLUGGED_AC);
batterylevel = intent.getIntExtra("level", 0);
updateAppWidget(context);
}
public void updateAppWidget(Context context){
RemoteViews updateViews = new RemoteViews(context.getPackageName(), R.layout.androidbatterywidget_layout);
updateViews.setTextViewText(R.id.textView1, " " + batterylevel + "%");
if (charging == 1)
updateViews.setImageViewResource(R.id.imageView2, R.drawable.bolt);
else if (status == BatteryManager.BATTERY_PLUGGED_USB)
updateViews.setImageViewResource(R.id.imageView2, R.drawable.usb);
else
updateViews.setImageViewResource(R.id.imageView2, R.drawable.empty);
Im sure that there is a far more "majestic" way to do this, but i was just puzzled at why the USB int was passed if it was plugged into USB (2), but not the AC (1).
Thanks!

Android Battery in SDK

Is there a way to get battery information from the Android SDK? Such as battery life remaining and so on? I cannot find it through the docs.

Here is a quick example that will get you the amount of battery used, the battery voltage, and its temperature.
Paste the following code into an activity:
#Override
public void onCreate() {
BroadcastReceiver batteryReceiver = new BroadcastReceiver() {
int scale = -1;
int level = -1;
int voltage = -1;
int temp = -1;
#Override
public void onReceive(Context context, Intent intent) {
level = intent.getIntExtra(BatteryManager.EXTRA_LEVEL, -1);
scale = intent.getIntExtra(BatteryManager.EXTRA_SCALE, -1);
temp = intent.getIntExtra(BatteryManager.EXTRA_TEMPERATURE, -1);
voltage = intent.getIntExtra(BatteryManager.EXTRA_VOLTAGE, -1);
Log.e("BatteryManager", "level is "+level+"/"+scale+", temp is "+temp+", voltage is "+voltage);
}
};
IntentFilter filter = new IntentFilter(Intent.ACTION_BATTERY_CHANGED);
registerReceiver(batteryReceiver, filter);
}
On my phone, this has the following output every 10 seconds:
ERROR/BatteryManager(795): level is 40/100 temp is 320, voltage is 3848
So this means that the battery is 40% full, has a temperature of 32.0 degrees celsius, and has voltage of 3.848 Volts.

You can register an Intent receiver to receive the broadcast for ACTION_BATTERY_CHANGED: http://developer.android.com/reference/android/content/Intent.html#ACTION_BATTERY_CHANGED. The docs say that the broadcast is sticky, so you'll be able to grab it even after the moment the battery state change occurs.

public static String batteryLevel(Context context)
{
Intent intent = context.registerReceiver(null, new IntentFilter(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;
return String.valueOf(percent) + "%";
}

I needed to have a monitor on the battery and check the Level and the status. I am developing on MonoForAndroid, so here is what I came up with. I am putting it here in case somebody have a similar requirement. (I have tested this and works nicely).
try
{
var ifilter = new IntentFilter(Intent.ActionBatteryChanged);
Intent batteryStatusIntent = Application.Context.RegisterReceiver(null, ifilter);
var batteryChangedArgs = new AndroidBatteryStateEventArgs(batteryStatusIntent);
_Battery.Level = batteryChangedArgs.Level;
_Battery.Status = batteryChangedArgs.BatteryStatus;
}
catch (Exception exception)
{
ExceptionHandler.HandleException(exception, "BatteryState.Update");
throw new BatteryUpdateException();
}
namespace Leopard.Mobile.Hal.Battery
{
public class AndroidBatteryStateEventArgs : EventArgs
{
public AndroidBatteryStateEventArgs(Intent intent)
{
Level = intent.GetIntExtra(BatteryManager.ExtraLevel, 0);
Scale = intent.GetIntExtra(BatteryManager.ExtraScale, -1);
var status = intent.GetIntExtra(BatteryManager.ExtraStatus, -1);
BatteryStatus = GetBatteryStatus(status);
}
public int Level { get; set; }
public int Scale { get; set; }
public BatteryStatus BatteryStatus { get; set; }
private BatteryStatus GetBatteryStatus(int status)
{
var result = BatteryStatus.Unknown;
if (Enum.IsDefined(typeof(BatteryStatus), status))
{
result = (BatteryStatus)status;
}
return result;
}
}
}
#region Internals
public class AndroidBattery
{
public AndroidBattery(int level, BatteryStatus status)
{
Level = level;
Status = status;
}
public int Level { get; set; }
public BatteryStatus Status { get; set; }
}
public class BatteryUpdateException : Exception
{
}
#endregion