Develop Reference

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.

Automatic update battery level in android

I am using this code to show battery level in my app. It works fine but doesn't update battery level automatically.
What should I do to update the battery level automatically.
public class MainActivity extends Activity {
private TextView txtBattery;
private BroadcastReceiver mBatteryLevelReciver = new BroadcastReceiver() {
#Override
public void onReceive(Context context, Intent intent) {
context.unregisterReceiver(this);
//int rawLevel = intent.getIntExtra("level", -1);
int rawLevel = intent.getIntExtra(BatteryManager.EXTRA_LEVEL, -1);
//int scale = intent.getIntExtra("scale", -1);
int scale = intent.getIntExtra(BatteryManager.EXTRA_SCALE, -1);
int level = -1;
if (rawLevel >= 0 && scale > 0) {
level = (rawLevel * 100) / scale;
}
txtBattery.setText("Battery3 Level Remaining :" + level + "%");
}
};
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
txtBattery = (TextView) findViewById(R.id.batterymeter_txt);
batteryLevel();
}
private void batteryLevel() {
IntentFilter batteryLevelFliter = new IntentFilter(Intent.ACTION_BATTERY_CHANGED);
registerReceiver(mBatteryLevelReciver, batteryLevelFliter);
}
}

Move the receiver variable to be a class attribute so it will be in memory when the intent is received:
public class Main extends Activity {
private TextView txtBattery;
private BroadcastReceiver mBatteryLevelReciver = new BroadcastReceiver() {
#Override
public void onReceive(Context context, Intent intent) {
//int rawLevel = intent.getIntExtra("level", -1);
int rawLevel = intent.getIntExtra(BatteryManager.EXTRA_LEVEL, -1);
//int scale = intent.getIntExtra("scale", -1);
int scale = intent.getIntExtra(BatteryManager.EXTRA_SCALE, -1);
int level = -1;
if (rawLevel >= 0 && scale > 0) {
level = (rawLevel * 100) / scale;
}
txtBattery.setText("Battery Level Remaining :" + level + "%");
}
};
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
txtBattery = (TextView) findViewById(R.id.batterymeter_txt);
batteryLevel();
}
private void batteryLevel() {
IntentFilter batteryLevelFliter = new IntentFilter(Intent.ACTION_BATTERY_CHANGED);
registerReceiver(batteryLevelReciver, batteryLevelFliter);
}

Why do you unregister your BroadcastReceiver in your onReceive() method?
context.unregisterReceiver(this);
Remove that.

try this code..
public class AndroidBattery extends Activity {
private TextView batteryLevel, batteryVoltage, batteryTemperature,
batteryTechnology, batteryStatus, batteryHealth;
/** Called when the activity is first created. */
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
batteryLevel = (TextView)findViewById(R.id.batterylevel);
batteryVoltage = (TextView)findViewById(R.id.batteryvoltage);
batteryTemperature = (TextView)findViewById(R.id.batterytemperature);
batteryTechnology = (TextView)findViewById(R.id.batterytechology);
batteryStatus = (TextView)findViewById(R.id.batterystatus);
batteryHealth = (TextView)findViewById(R.id.batteryhealth);
this.registerReceiver(this.myBatteryReceiver,
new IntentFilter(Intent.ACTION_BATTERY_CHANGED));
}
private BroadcastReceiver myBatteryReceiver
= new BroadcastReceiver(){
#Override
public void onReceive(Context arg0, Intent arg1) {
// TODO Auto-generated method stub
if (arg1.getAction().equals(Intent.ACTION_BATTERY_CHANGED)){
batteryLevel.setText("Level: "
+ String.valueOf(arg1.getIntExtra("level", 0)) + "%");
batteryVoltage.setText("Voltage: "
+ String.valueOf((float)arg1.getIntExtra("voltage", 0)/1000) + "V");
batteryTemperature.setText("Temperature: "
+ String.valueOf((float)arg1.getIntExtra("temperature", 0)/10) + "c");
batteryTechnology.setText("Technology: " + arg1.getStringExtra("technology"));
int status = arg1.getIntExtra("status", BatteryManager.BATTERY_STATUS_UNKNOWN);
String strStatus;
if (status == BatteryManager.BATTERY_STATUS_CHARGING){
strStatus = "Charging";
} else if (status == BatteryManager.BATTERY_STATUS_DISCHARGING){
strStatus = "Dis-charging";
} else if (status == BatteryManager.BATTERY_STATUS_NOT_CHARGING){
strStatus = "Not charging";
} else if (status == BatteryManager.BATTERY_STATUS_FULL){
strStatus = "Full";
} else {
strStatus = "Unknown";
}
batteryStatus.setText("Status: " + strStatus);
int health = arg1.getIntExtra("health", BatteryManager.BATTERY_HEALTH_UNKNOWN);
String strHealth;
if (health == BatteryManager.BATTERY_HEALTH_GOOD){
strHealth = "Good";
} else if (health == BatteryManager.BATTERY_HEALTH_OVERHEAT){
strHealth = "Over Heat";
} else if (health == BatteryManager.BATTERY_HEALTH_DEAD){
strHealth = "Dead";
} else if (health == BatteryManager.BATTERY_HEALTH_OVER_VOLTAGE){
strHealth = "Over Voltage";
} else if (health == BatteryManager.BATTERY_HEALTH_UNSPECIFIED_FAILURE){
strHealth = "Unspecified Failure";
} else{
strHealth = "Unknown";
}
batteryHealth.setText("Health: " + strHealth);
}
}
};
}

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.permission.BATTERY_STATS api

I want more information about android.permission.BATTERY_STATS . what possibilities grants the permission android.permission.BATTERY_STATS. I know how to use it if I can read the android.intent.action.BATTERY_CHANGED intent for the battery levels without declare such permission.

use this code that will get you the amount of battery used, the battery voltage, and its temperature.
#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);
}

Android Development: Show Battery Level

I've been searching for this and only find really messed up things.
Isn't there a easy way to show the battery level like 21% on a toast or Textview?
Or how can i achieve this?
//Simon

To get the battery level right now, call:
registerReceiver(null, new IntentFilter(Intent.ACTION_BATTERY_CHANGED));
(note: typing that in from memory, please adjust if needed)
This will return an Intent with various extras documented on the BatteryManager class. Use BatteryManager.EXTRA_LEVEL and BatteryManager.EXTRA_SCALE to determine the percentage remaining.
If you need to know over a period of time as the battery changes, use the BroadcastReceiver approach #Augusto outlined in his answer.

if you mean changing the battery status on the emulator do the following. Connect to the emulator via telnet and change the status and capacity
> telnet localhost 5554
Android Console: type 'help' for a list of commands
OK
power ac off
OK
power discharging
OK
power capacity 21
OK
exit
>
Ahh, well you can do what it says on the page Ted mentioned, and then use a handler to show a toast. This is the code you need to add to your activity.
private Handler handler = new Handler;
private BroadcastReceiver mBatInfoReceiver = new BroadcastReceiver() {
#Override
public void onReceive(final Context context, Intent intent) {
int level = intent.getIntExtra(BatteryManager.EXTRA_LEVEL, 0);
int scale = intent.getIntExtra(BatteryManager.EXTRA_SCALE, 100);
Log.i(TAG, "level: " + level + "; scale: " + scale);
int percent = (level*100)/scale;
final String text = String.valueOf(percent) + "%";
handler.post( new Runnable() {
public void run() {
Toast.makeText(context, text, Toast.LENGTH_SHORT).show();
}
});
}
};

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) + "%";
}

You can use this.
private void batteryLevel() {
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;
}
batterLevel.setText("Battery Level Remaining: " + level + "%");
}
};
IntentFilter batteryLevelFilter = new IntentFilter(Intent.ACTION_BATTERY_CHANGED);
registerReceiver(batteryLevelReceiver, batteryLevelFilter);
}

I used a combination like that:
BatteryManager bm = (BatteryManager) getActivity().getSystemService(BATTERY_SERVICE);
int batLevel = 100;
int level;
int scale;
if (android.os.Build.VERSION.SDK_INT >= android.os.Build.VERSION_CODES.LOLLIPOP) {
batLevel = bm.getIntProperty(BatteryManager.BATTERY_PROPERTY_CAPACITY);
}
if(batLevel == 0){
Intent intent = getActivity().registerReceiver(null, new IntentFilter(Intent.ACTION_BATTERY_CHANGED));
level = intent.getIntExtra(BatteryManager.EXTRA_LEVEL, 0);
scale = intent.getIntExtra(BatteryManager.EXTRA_SCALE, 100);
batLevel = (level*100)/scale;
}
I did it like that because on a Nexus 5 device with Marshmallow "batLevel" returned 0 always. That solved it completely!
Good luck