Develop Reference

How to get the battery level in background and announce it?

In my app, I want to get the battery level in the background because I want to announce it in the text to speech when the battery level is low or when the battery is full or at any level. I have used the broadcast receivers and can get the battery level but don't know how to get it in the background.
Anyone can help?

The thing that you want to achieve can be done via intent Service, if you dig in the docs you can find it yourself, here is the link Intent Service, This type of intent can be fired in the background and can be used to perform various simple operations such as yours, because they don't have any interface but rather just operations executed in background.
Also here is a video guide Background Services which you can use for yourself to get battery percentage and announce it after a certain condition
Edit 2:
(Nothing Required in XML as this is a background process/operation)
This is a code to get the battery percentage and announce it using Text to speech in broadcast receiver,
MainActivity.java
package com.example.text_to_speech;
import android.app.AlarmManager;
import android.app.PendingIntent;
import android.content.Context;
import android.content.Intent;
import android.os.Bundle;
import android.speech.tts.TextToSpeech;
import android.widget.Button;
import androidx.appcompat.app.AppCompatActivity;
public class MainActivity extends AppCompatActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Intent intent=new Intent(this,myBackgroundProcess.class);
intent.setAction("BackgroundProcess");
PendingIntent pendingIntent=PendingIntent.getBroadcast(this,0,intent,0);
AlarmManager alarmManger= (AlarmManager) getSystemService(Context.ALARM_SERVICE);
alarmManger.setRepeating(AlarmManager.RTC_WAKEUP,0,10,pendingIntent);//change this time based on your liking which will fire the intent
}
}
customerclass- myBackgroundProcess.java
package com.example.text_to_speech;
import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.os.BatteryManager;
import android.speech.tts.TextToSpeech;
import android.util.Log;
import java.util.Locale;
import static android.content.Context.BATTERY_SERVICE;
public class myBackgroundProcess extends BroadcastReceiver {
private TextToSpeech mTTS;
#Override
public void onReceive(Context context, Intent intent) {
mTTS = new TextToSpeech(context.getApplicationContext(), new TextToSpeech.OnInitListener() {
#Override
public void onInit(int status) {
if (status != TextToSpeech.ERROR) {
int result = mTTS.setLanguage(Locale.US);
if (result == TextToSpeech.LANG_MISSING_DATA
|| result == TextToSpeech.LANG_NOT_SUPPORTED) {
Log.e("TTS", "Language not supported");
} else {
BatteryManager bm = (BatteryManager) context.getSystemService(BATTERY_SERVICE);
int batLevel = bm.getIntProperty(BatteryManager.BATTERY_PROPERTY_CAPACITY);
if(batLevel==100 || batLevel<=10 || batLevel==50)
speak(context,batLevel);
}
} else {
Log.e("TTS", "Initialization failed");
}
}
});
}
public void speak(Context context, int batlevel)
{
mTTS.setPitch(10);
mTTS.setSpeechRate(1);
String text=String.valueOf(batlevel);
mTTS.speak(text, TextToSpeech.QUEUE_FLUSH, null);
}
}
In Android Manifest Register the receiver and add intent filter to it as shown below (below application tag)
<receiver android:name=".myBackgroundProcess"
android:enabled="true"
android:exported="true"
>
<intent-filter>
<action android:name="BackgroundProcess"/>
</intent-filter>
</receiver>

How to make Android Direct Reply Notification feature work in pre - Android N devices?

I am trying to implement Android Direct Reply notification in my app. I've managed to implement it successfully in Android N emulator. But it is not working on Marshmallow devices. When I click on action button in notification the reply edittext is not showing in devices below Android N. I know this feature will work in pre Android N devices, as it is available in WhatsApp.
My question is how to make it work in pre Android N devices? I'm sharing my code here. Any help would be great. Thanks.
MainActivity
import android.app.Notification;
import android.app.NotificationManager;
import android.app.PendingIntent;
import android.app.RemoteInput;
import android.content.Context;
import android.content.Intent;
import android.os.Bundle;
import android.support.design.widget.FloatingActionButton;
import android.support.v7.app.AppCompatActivity;
import android.support.v7.widget.Toolbar;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
public class MainActivity extends AppCompatActivity {
// Key for the string that's delivered in the action's intent.
public static final String KEY_TEXT_REPLY = "key_text_reply";
private static final int notificationID = 1234;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
FloatingActionButton fab = (FloatingActionButton) findViewById(R.id.fab);
fab.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
startNotif();
}
});
}
private void startNotif() {
Intent intent = new Intent(this, NotificationReciever.class);
// use System.currentTimeMillis() to have a unique ID for the pending intent
final PendingIntent pIntent = PendingIntent.getActivity(this, (int) System.currentTimeMillis(), intent, 0);
String replyLabel = "Reply";
RemoteInput remoteInput = new RemoteInput.Builder(KEY_TEXT_REPLY)
.setLabel(replyLabel)
.build();
// Create the reply action and add the remote input.
Notification.Action action =
new Notification.Action.Builder(R.drawable.ic_send,
"Action", pIntent)
.addRemoteInput(remoteInput)
.build();
// Build the notification and add the action.
Notification newMessageNotification =
new Notification.Builder(MainActivity.this)
.setSmallIcon(R.drawable.ic_remove_circle_black_48dp)
.setContentTitle("Title")
.setContentText("Content")
.addAction(action).build();
// Issue the notification.
NotificationManager manager = (NotificationManager) getSystemService(Context.NOTIFICATION_SERVICE);
manager.notify(notificationID, newMessageNotification);
}
}
NotificationReciever
import android.app.Activity;
import android.app.RemoteInput;
import android.content.Intent;
import android.os.Bundle;
import android.widget.Toast;
/**
* Created by User on 13-Jun-16.
*/
public class NotificationReciever extends Activity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
Toast.makeText(this,getMessageText(getIntent()),Toast.LENGTH_SHORT).show();
}
private CharSequence getMessageText(Intent intent) {
Bundle remoteInput = RemoteInput.getResultsFromIntent(intent);
if (remoteInput != null) {
return remoteInput.getCharSequence(MainActivity.KEY_TEXT_REPLY);
}
Toast.makeText(this,"Remoteinput is null",Toast.LENGTH_SHORT).show();
return null;
}
}

In the docs it tells you to not use a broadcast receiver or a service for api below N. So you'd have to launch an activity which does what you want and wrap it in a pending intent instead.
if (isDirectReplySupported) {
return PendingIntent.getBroadcast(context, 0, intent, PendingIntent.FLAG_ONE_SHOT);
}
return PendingIntent.getActivity(context, 0, intent, PendingIntent.FLAG_UPDATE_CURRENT);

Implementing this feature is very simple, first make one broadcastreceiver, as usual create a action button & hook up with pendingintent.
Then connect that intent to push notification object & notify.
In broadcastreceiver handle the reading text part & updating to notification.
Refer this post for sample example http://www.feelzdroid.com/2017/01/android-n-inline-reply-push-notifications.html

How do I create an Android notification?

I followed their tutorial step by step but I keep getting strange errors.
The notifymanager doesn't have .notify() as a method and any line of code with notifymanager in it must have brackets regardless of where it is within the code.
I'm beginning to think it's a dependency issue, please help!

Activity 1
import android.os.Bundle;
import android.app.Activity;
import android.app.Notification;
import android.app.NotificationManager;
import android.app.PendingIntent;
import android.content.Context;
import android.content.Intent;
public class NotificationAlert extends Activity {
private static final int NOTIFY_ME_ID=1337;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.notification_alert);
/*********** Create notification ***********/
final NotificationManager mgr=
(NotificationManager)this.getSystemService(Context.NOTIFICATION_SERVICE);
Notification note=new Notification(R.drawable.stat_notify_chat,
"Android Example Status message!",
System.currentTimeMillis());
// This pending intent will open after notification click
PendingIntent i=PendingIntent.getActivity(this, 0,
new Intent(this, NotifyMessage.class),
0);
note.setLatestEventInfo(this, "Android Example Notification Title",
"This is the android example notification message", i);
//After uncomment this line you will see number of notification arrived
//note.number=2;
mgr.notify(NOTIFY_ME_ID, note);
}
}
Activity 2
import android.app.Activity;
import android.os.Bundle;
import android.widget.TextView;
public class NotifyMessage extends Activity {
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
TextView txt=new TextView(this);
txt.setText("Activity after click on notification");
setContentView(txt);
}
}

How to wake up my App Periodically

I want to make an functionality, like reminder, in Android.
I want to start-up my app/activity, when it is not running, or its UI is invisible.
It is some-thing like same as reminder, that wakes ups the app at desired time.
I have not worked with any type of background task or service,
so I haven't any idea that what to do,
or what type of classes or demos should be studied by me?
Can any one give me some suggestions with demos or tutorials links.
Thanks, in advance.

Hi use the following code. This is service. By using pending Intent with alarm manager you can open your UI at your needed time.
import java.util.Calendar;
import java.util.Timer;
import java.util.TimerTask;
import android.app.AlarmManager;
import android.app.PendingIntent;
import android.app.Service;
import android.content.Context;
import android.content.Intent;
import android.database.Cursor;
import android.os.Handler;
import android.os.IBinder;
import android.os.Message;
import android.util.Log;
public class ScheduleCheckService extends Service{
private Timer timer;
final int REFRESH=0;
Context context;
private PendingIntent pendingIntent;
#Override
public IBinder onBind(Intent intent) {
// TODO Auto-generated method stub
return null;
}
#Override
public void onCreate() {
// TODO Auto-generated method stub
super.onCreate();
context=this;
//==============================================
TimerTask refresher;
// Initialization code in onCreate or similar:
timer = new Timer();
refresher = new TimerTask() {
public void run() {
handler.sendEmptyMessage(0);
};
};
// first event immediately, following after 1 seconds each
timer.scheduleAtFixedRate(refresher, 0,1000);
//=======================================================
}
final Handler handler = new Handler() {
public void handleMessage(Message msg) {
switch (msg.what) {
case REFRESH:
//your code here
break;
default:
break;
}
}
};
void PendingIntentmethod()
{
Intent myIntent = new Intent(context, YOURCLASS.class);
pendingIntent = PendingIntent.getActivity(context, 0, myIntent, 0);
AlarmManager alarmManager = (AlarmManager)getSystemService(ALARM_SERVICE);
Calendar calendar = Calendar.getInstance();
}
}
Start the service and stop the service when you want and also dont forget to register it in manifest file.

Have a look at the Android Service class.
http://developer.android.com/reference/android/app/Service.html
From this Service you can periodically start (using a TimerTask) an Intent to open your App or just set a Notification, from which the user can open the App with the desired Activity. I would prefer the second option, because he user doesn't want an Application just to be opened at some time.
Here is a simple Service Tutorial:
http://www.vogella.com/articles/AndroidServices/article.html

launch activity from service when notification is clicked

I know, there are tons of these on here, but I've been trying solutions all day and haven't gotten anywhere.
Neither the example on google's docs, nor any of the 5 other ways I've found on here have worked for me at all.
As is the typical case, when I click the notification it closes the status bar and nothing new is shown onscreen.
I am creating the notification from a service and need the notification to trigger a new activity that has not yet been created.
I also will need a way to pass information to that activity via intent.
And yes... this is java for Android
What follows are the shattered remnants of my code.
package com.bobbb.hwk2;
import java.io.FileOutputStream;
import android.app.Notification;
import android.app.NotificationManager;
import android.app.PendingIntent;
import android.app.Service;
import android.content.ContentResolver;
import android.content.Context;
import android.content.Intent;
import android.database.Cursor;
import android.net.Uri;
import android.os.IBinder;
import android.provider.ContactsContract;
import android.widget.Toast;
public class contactBackup extends Service
{
private NotificationManager nManager;
private static final int NOTIFY_ID = 1100;
#Override
public void onCreate()
{
super.onCreate();
String ns = Context.NOTIFICATION_SERVICE;
nManager = (NotificationManager)getSystemService(ns);
}
#Override
public void onStart(Intent intent, int startId) {
super.onStart(intent, startId);
// inform user that service has started
Toast.makeText(getApplicationContext(), R.string.service_started,Toast.LENGTH_LONG).show();
String data = lookUpContacts();
if( saveToSDCard(getResources().getString(R.string.backup_file_name),data) )
{
Context context = getApplicationContext();
// create the statusbar notification
Intent nIntent = new Intent(this,contactViewer.class);//Intent nIntent = new Intent(Intent.ACTION_MAIN);
nIntent.setClass(context,contactViewer.class);
//nIntent.putExtra("data",data);
Notification msg = new Notification(R.drawable.icon,"All contacts records have been written to the file.",System.currentTimeMillis());
// start notification
//PendingIntent pIntent = PendingIntent.getService(getApplicationContext(),0,nIntent,PendingIntent.FLAG_UPDATE_CURRENT|Intent.FLAG_FROM_BACKGROUND);
PendingIntent pIntent = PendingIntent.getActivity(this,0,nIntent,0);
msg.flags = Notification.FLAG_AUTO_CANCEL;
msg.setLatestEventInfo(context,
"success",
"All contacts records have been written to the file.",
pIntent);
nManager.notify(NOTIFY_ID,msg);
}
}
#Override
public void onDestroy()
{
nManager.cancel(NOTIFY_ID);
super.onDestroy();
}
#Override
public IBinder onBind(Intent intent)
{
return null;
}
// function returns string containing information
// from contacts
public String lookUpContacts()
{
...
}
public boolean saveToSDCard(String fileName, String data)
{
...
}
}
I can only hope that whatever is causing my problem is something fixable and not more of the crazy glitches I've been getting with eclipse (which no one else seems to have ever seen >:U )
If you can help me solve this problem, please share.
If you can't help with this specific problem but feel obligated to say unrelated things about posting, styles, topics, or good practice, then DON'T
Thank you :D

Edit:
You're going to have to add a flag for FLAG_ACTIVITY_NEW_TASK:
nIntent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
This is because you're launching from outside your app (from the system notification bar).

This is what happens when people overwork themselves. XD
The only reason none of the tutorials I tired worked is because I misspelled my activity name in the manifest.
Thanks for stopping by

Just add following in contactBackup(service class),
Intent nIntent = new Intent(this,contactViewer.class);//Intent nIntent = new Intent(Intent.ACTION_MAIN);
nIntent.setClass(context,contactViewer.class);
nIntent.putExtra("data",data);
nIntent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
Notification msg = new Notification(R.drawable.icon,"All contacts records have been written to the file.",System.currentTimeMillis());
// start notification
//PendingIntent pIntent = PendingIntent.getService(getApplicationContext(),0,nIntent,PendingIntent.FLAG_UPDATE_CURRENT|Intent.FLAG_FROM_BACKGROUND);
PendingIntent pIntent = PendingIntent.getActivity(this,0,nIntent,0);
msg.flags = Notification.FLAG_AUTO_CANCEL;
msg.setLatestEventInfo(context,
"success",
"All contacts records have been written to the file.",
pIntent);
nManager.notify(NOTIFY_ID,msg);
then get value in contactViewer class,
as,
String s=getIntent().getStringExtra("data");