Develop Reference

Unable to register broadcast receiver

I am trying to detect internet connectivity using broadcast receiver. I have registered broadcast receiver dynamically but when app launches it is showing error below:
java.lang.IllegalArgumentException: Receiver not registered: com.app.qrius.ConnectivityReceiver#3240fd8
I want to redirect to another activity which shows not network message when there is no internet connection.
Below is my code:
ConnectivityReceiver.java
public class ConnectivityReceiver extends BroadcastReceiver {
#Override
public void onReceive(Context context, Intent intent) {
ConnectivityManager connectivityManager = (ConnectivityManager) context.getSystemService(context.CONNECTIVITY_SERVICE);
NetworkInfo networkInfo = connectivityManager.getActiveNetworkInfo();
if(networkInfo != null){
Toast.makeText(context,"On",Toast.LENGTH_SHORT).show();
}
else{
Intent i = new Intent(context,Network.class);
context.startActivity(i);
((Activity)context).finish();
}
}
MainActivity.java
public class MainActivity extends AppCompatActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
final Toolbar toolbar = findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
}
#Override
protected void onResume() {
LocalBroadcastManager.getInstance(this).registerReceiver(
mMessageReceiver, new IntentFilter("android.net.conn.CONNECTIVITY_CHANGE"));
super.onResume();
}
private BroadcastReceiver mMessageReceiver = new BroadcastReceiver() {
#Override
public void onReceive(Context context, Intent intent) {
// TODO Auto-generated method stub
// Get extra data included in the Intent
ConnectivityManager connectivityManager = (ConnectivityManager) context.getSystemService(context.CONNECTIVITY_SERVICE);
NetworkInfo networkInfo = connectivityManager.getActiveNetworkInfo();
if(networkInfo != null){
Toast.makeText(context,"On",Toast.LENGTH_SHORT).show();
}
else{
// Toast.makeText(context,"Off",Toast.LENGTH_SHORT).show();
Intent i = new Intent(context,Network.class);
context.startActivity(i);
((Activity)context).finish();
}
}
};
}
What am I doing wrong?

You would need to add it to the AndroidManifest.xml
Similar to:
<receiver
android:name=".BatteryPowerBroadcastReceiver"
android:enabled="true"
android:exported="true">
<intent-filter>
<action android:name="android.intent.action.ACTION_POWER_CONNECTED" />
<action android:name="android.intent.action.ACTION_POWER_DISCONNECTED" />
<action android:name="android.intent.action.BATTERY_LOW" />
<action android:name="android.intent.action.BATTERY_OKAY" />
<action android:name="android.intent.action.DOCK_EVENT" />
</intent-filter>
</receiver>

You should change your activity as below for programmatically register and unregister broadcast receiver. You can use LocalBroadcastManager for this.
public class MainActivity extends AppCompatActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
final Toolbar toolbar = findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
}
#Override
protected void onResume() {
// Register to receive messages.
// We are registering an observer (mMessageReceiver) to receive
// Intents
IntentFilter intentFilter = new IntentFilter();
intentFilter.addAction("android.net.conn.CONNECTIVITY_CHANGE");
LocalBroadcastManager.getInstance(this).registerReceiver(
mMessageReceiver, intentFilter);
super.onResume();
}
#Override
protected void onPause() {
// Unregister since the activity is paused.
LocalBroadcastManager.getInstance(this).unregisterReceiver(
mMessageReceiver);
super.onPause();
}
// Our handler for received Intents. This will be called whenever an Intent
// with an action named "custom-event-name" is broadcasted.
private BroadcastReceiver mMessageReceiver = new BroadcastReceiver() {
#Override
public void onReceive(Context context, Intent intent) {
// TODO Auto-generated method stub
// Get extra data included in the Intent
ConnectivityManager connectivityManager = (ConnectivityManager) context.getSystemService(context.CONNECTIVITY_SERVICE);
NetworkInfo networkInfo = connectivityManager.getActiveNetworkInfo();
if(networkInfo != null){
Toast.makeText(context,"On",Toast.LENGTH_SHORT).show();
}
else{
Intent i = new Intent(context,Network.class);
context.startActivity(i);
((Activity)context).finish();
}
}
};
}
For more info, please check

Broadcast Receiver is not working when pressing back (Back to already opened activity)

I have a BroadcastReceiver
Manifest
<receiver android:name=".NetworkStateChecker">
<intent-filter >
<action android:name="android.net.conn.CONNECTIVITY_CHANGE"
/>
</intent-filter>
</receiver>
this is the class
public class NetworkStateChecker extends BroadcastReceiver {
#Override
public void onReceive(Context context, Intent intent) {
this.context = context;
ConnectivityManager cm = (ConnectivityManager) context.getSystemService(Context.CONNECTIVITY_SERVICE);
activeNetwork = cm.getActiveNetworkInfo();
if (activeNetwork != null) {
if (activeNetwork.getType() == ConnectivityManager.TYPE_WIFI || activeNetwork.getType() == ConnectivityManager.TYPE_MOBILE) {
new AutoTask().execute("start");
}
}
}
}
and when the asynctask is done i call this
context.sendBroadcast(new Intent(act1.DATA_SAVED_BROADCAST));
context.sendBroadcast(new Intent(act2.DATA_SAVED_BROADCAST));
context.sendBroadcast(new Intent(act3.DATA_SAVED_BROADCAST));
here is my sample in one of those activity
public class act1extends AppCompatActivity {
public static final String DATA_SAVED_BROADCAST = "website link";
private BroadcastReceiver broadcastReceiver;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity1);
registerReceiver(new NetworkStateChecker(), new IntentFilter(ConnectivityManager.CONNECTIVITY_ACTION));
//Codes here
broadcastReceiver = new BroadcastReceiver() {
#Override
public void onReceive(Context context, Intent intent) {
//Codes here
}
};
registerReceiver(broadcastReceiver, new IntentFilter(DATA_SAVED_BROADCAST));
}
}
here is the scenario. I will go to an activity do some stuff and return to the activity above after the broadcast receiver works. next is when i go to another activity and do some stuff there after pressing back the broadcast doesnt work
whats the problem? how can i fix it?

Need to display error until internet connection is turned on in android

I want to check whether Internet connection is turned on or not when app starts. It should allow to start if internet is connected. Else display a error message and direct user to settings. Message need to be displayed until Internet connection is turned on.
Already I finished connection check function and alert display function. How could I listen whether internet is turned on or not after user directed to settings
connection check function is,
public boolean connectionIsAvailable(Context context) {
ConnectivityManager cm = (ConnectivityManager) context.getSystemService(Context.CONNECTIVITY_SERVICE);
NetworkInfo wifiNetwork = cm.getNetworkInfo(ConnectivityManager.TYPE_WIFI);
if (wifiNetwork != null && wifiNetwork.isConnected()) {
return true;
}
NetworkInfo mobileNetwork = cm.getNetworkInfo(ConnectivityManager.TYPE_MOBILE);
if (mobileNetwork != null && mobileNetwork.isConnected()) {
return true;
}
NetworkInfo activeNetwork = cm.getActiveNetworkInfo();
if (activeNetwork != null && activeNetwork.isConnected()) {
return true;
}
return false;
}
and alert display,
public void displayAlertDialog(final Context context){
AlertDialog.Builder alertDialogBuilder = new AlertDialog.Builder(context, AlertDialog.THEME_TRADITIONAL);
alertDialogBuilder.setMessage("Would you like to enable it?")
.setTitle("No Internet Connection")
.setPositiveButton(" Enable Internet ", new DialogInterface.OnClickListener(){
public void onClick(DialogInterface dialog, int id){
Intent dialogIntent = new Intent(android.provider.Settings.ACTION_SETTINGS);
dialogIntent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
context.startActivity(dialogIntent);
}
});
alertDialogBuilder.setNegativeButton(" Cancel ", new DialogInterface.OnClickListener(){
public void onClick(DialogInterface dialog, int id){
dialog.cancel();
}
});
AlertDialog alert = alertDialogBuilder.create();
alert.show();
}
In my onCreate I check like,
if(connectionIsAvailable(getApplicationContext())) {
welcomeThread.start();
} else {
displayAlertDialog(LoadingScreenActivity.this);
}
Help me how could I listen whether internet is turned on or not after user directed to settings. Thanks in advance.

Register receiver in manifest file
<!-- Broadcast receiver declaration in manifest file and make sure to enable it -->
<receiver
android:name=".InternetConnectorReceiver"
android:enabled="true">
<intent-filter>
<!-- Intent filters for broadcast receiver -->
<action android:name="android.net.conn.CONNECTIVITY_CHANGE" />
<action android:name="android.net.wifi.WIFI_STATE_CHANGED" />
<action android:name="android.net.wifi.STATE_CHANGE" />
</intent-filter>
</receiver>
Required permissions
<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />
<uses-permission android:name="android.permission.INTERNET" />
InternetConnectorReceiver.class
public class InternetConnectorReceiver extends BroadcastReceiver {
// you can perform the action based on InternetConnected or not based on value of this variable.
public static boolean IsInternetConnected = true;
public InternetConnectorBroadcastReceiver() {
}
#Override
public void onReceive(Context context, Intent intent) {
try {
boolean isVisible = NameOfapplicationclass.isActivityVisible();
// If it is visible then trigger the task else do nothing
if (isVisible == true) {
if (isInternetConnected(context)) {
IsInternetConnected = true;
}
else
{
IsInternetConnected = false;
}
}
} catch (Exception e) {
e.printStackTrace();
}
}
}
public static boolean isInternetConnected(Context context) {
ConnectivityManager cmObj = (ConnectivityManager) context.getSystemService(Context.CONNECTIVITY_SERVICE);
NetworkInfo activeNetwork = cmObj.getActiveNetworkInfo();
if (activeNetwork != null && activeNetwork.isConnected()) {
return true;
}
return false;
}
Add Following code in application class
public static boolean activityVisible;
public static boolean isActivityVisible() {
return activityVisible; // return true or false
}
public static void activityResumed() {
activityVisible = true;// this will set true when activity resumed
}
public static void activityPaused() {
activityVisible = false;// this will set false when activity paused
}

You have to use BroadcasrReceive
try this.
Create class for BroadcastReceiver
public class NetworkChangeReceiver extends BroadcastReceiver {
#Override
public void onReceive(final Context context, final Intent intent) {
//Do your code
}
}
and register it in manifest file like this
<receiver android:name=".NetworkChangeReceiver" >
<intent-filter>
<action android:name="android.net.conn.CONNECTIVITY_CHANGE" />
</intent-filter>
</receiver>

Manifest:
<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />
<!--Custom Broadcast Receiver for checking Internet Connectivity-->
<receiver
android:name=".extras.ConnectivityReceiver"
android:enabled="true">
<intent-filter>
<action android:name="android.net.conn.CONNECTIVITY_CHANGE" />
</intent-filter>
</receiver>
<!--End-->
Connectivity Receiver Class:
public class ConnectivityReceiver extends BroadcastReceiver {
public static ConnectivityReceiverListener connectivityReceiverListener;
public ConnectivityReceiver() {
super();
}
#Override
public void onReceive(Context context, Intent arg1) {
ConnectivityManager cm = (ConnectivityManager) context
.getSystemService(Context.CONNECTIVITY_SERVICE);
NetworkInfo activeNetwork = cm.getActiveNetworkInfo();
boolean isConnected = activeNetwork != null
&& activeNetwork.isConnectedOrConnecting();
if (connectivityReceiverListener != null) {
connectivityReceiverListener.onNetworkConnectionChanged(isConnected);
}
}
/**
* Checking if internet connection is active or not
* #return
*/
public static boolean isConnected() {
ConnectivityManager
cm = (ConnectivityManager) MyApplication.getInstance().getApplicationContext()
.getSystemService(Context.CONNECTIVITY_SERVICE);
NetworkInfo activeNetwork = cm.getActiveNetworkInfo();
return activeNetwork != null
&& activeNetwork.isConnectedOrConnecting();
}
public interface ConnectivityReceiverListener {
void onNetworkConnectionChanged(boolean isConnected);
}
}
Activity Code:
public class HomeActivity extends AppCompatActivity
implements ConnectivityReceiver.ConnectivityReceiverListener {
/**
* Callback will be triggered when there is change in
* network connection
*/
#Override
public void onNetworkConnectionChanged(boolean isConnected) {
if (!isConnected) {
// show dialog \\
} else {
// check if dialog is visible \\
// if visible then dismiss else do your stuff \\
}
}
#Override
protected void onResume() {
super.onResume();
// Register connection status listener \\
MyApplication.getInstance().setConnectivityListener(this);
}
}
My Application class code and set it in manifest:
public class MyApplication extends Application {
private static MyApplication mInstance;
#Override
public void onCreate() {
super.onCreate();
mInstance = this;
}
public static synchronized MyApplication getInstance() {
return mInstance;
}
//-------Broadcast Receiver for Checking Internet Connection----------\\
public void setConnectivityListener(ConnectivityReceiver.ConnectivityReceiverListener listener) {
ConnectivityReceiver.connectivityReceiverListener = listener;
}
//----------------------------------------------------------------------\\
}

When phone's network status changed, it will send a broadcast. So you just need a BroadcastReceiver.
For more detail check official documentation

Update UI from static BroadcastReceiver

I've checked this example of how to handle network connectivity changes:
Android Check Internet Connection and found a very nice piece of code of how to handle this changes:
public class NetworkChangeReceiver extends BroadcastReceiver {
#Override
public void onReceive(final Context context, final Intent intent) {
String status = NetworkUtil.getConnectivityStatusString(context); //some internal class to determinate which type is connected
Toast.makeText(context, status, Toast.LENGTH_LONG).show();
}
}
To make this thing work I need to declare this BroadcastReceiver inside my manifest file:
<application ...>
...
<receiver
android:name="net.viralpatel.network.NetworkChangeReceiver"
android:label="NetworkChangeReceiver" >
<intent-filter>
<action android:name="android.net.conn.CONNECTIVITY_CHANGE" />
<action android:name="android.net.wifi.WIFI_STATE_CHANGED" />
</intent-filter>
</receiver>
...
</application>
Now I want to update UI, when wifi/mobile data is connected.
I can either make the NetworkChangeReceiver class inner static or external. But what I need is that I can work with my MainActivity UI from public void onReceive. How I can do this?

The answer was easy. I don't need to register my broadcast in order to get broadcast about connectivity change:
private BroadcastReceiver networkConnectivityReciever = new BroadcastReceiver() {
public void onReceive(Context context, Intent intent) {
NetworkInfo currentNetworkInfo = intent.getParcelableExtra(ConnectivityManager.EXTRA_NETWORK_INFO);
if (dialog != null) {
if(currentNetworkInfo.isConnected()){
dialog.dismiss();
webView.reload();
}else{
dialog.show(((MainActivity) context).getSupportFragmentManager(), "");
}
}
}
};
#Override
protected void onResume() {
super.onResume();
registerReceiver(networkConnectivityReciever,
new IntentFilter(ConnectivityManager.CONNECTIVITY_ACTION));
}
#Override
protected void onPause() {
super.onPause();
unregisterReceiver(networkConnectivityReciever);
}
And only thing I need in manifest is this:
<uses-permission android:name="android.permission.INTERNET" />
<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />

Kiosk mode is not working.?

I am creating sample app with kiosk mode in my app to check that is kiosk mode work or not.?. But in sample app kiosk mode is not working. I means after screen goes off activity is not starting.
I have taken this from [http://www.andreas-schrade.de/2015/02/16/android-tutorial-how-to-create-a-kiosk-mode-in-android/][here]
THis is my main activity
public class MainActivity extends Activity{
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
getWindow().addFlags(WindowManager.LayoutParams.FLAG_DISMISS_KEYGUARD);
setContentView(R.layout.activity_main);
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.main, menu);
return true;
}
#Override
public boolean onOptionsItemSelected(MenuItem item) {
// Handle action bar item clicks here. The action bar will
// automatically handle clicks on the Home/Up button, so long
// as you specify a parent activity in AndroidManifest.xml.
int id = item.getItemId();
if (id == R.id.action_settings) {
return true;
}
return super.onOptionsItemSelected(item);
}
#Override
public void onWindowFocusChanged(boolean hasFocus) {
super.onWindowFocusChanged(hasFocus);
if(!hasFocus) {
// Close every kind of system dialog
Intent closeDialog = new Intent(Intent.ACTION_CLOSE_SYSTEM_DIALOGS);
sendBroadcast(closeDialog);
}
}
}
THis is my Application class
public class AppContext extends Application {
private AppContext instance;
private PowerManager.WakeLock wakeLock;
private OnScreenOffReceiver onScreenOffReceiver;
PowerManager pm;
#Override
public void onCreate() {
super.onCreate();
instance = this;
registerKioskModeScreenOffReceiver();
pm = (PowerManager) getSystemService(Context.POWER_SERVICE);
startKioskService();
}
private void registerKioskModeScreenOffReceiver() {
// register screen off receiver
final IntentFilter filter = new IntentFilter(Intent.ACTION_SCREEN_OFF);
onScreenOffReceiver = new OnScreenOffReceiver();
registerReceiver(onScreenOffReceiver, filter);
}
public PowerManager.WakeLock getWakeLock() {
if(wakeLock == null) {
// lazy loading: first call, create wakeLock via PowerManager.
wakeLock = pm.newWakeLock(PowerManager.FULL_WAKE_LOCK | PowerManager.ACQUIRE_CAUSES_WAKEUP, "wakeup");
}
return wakeLock;
}
private void startKioskService() { // ... and this method
startService(new Intent(this, KioskService.class));
}
}
This is receiver class
public class OnScreenOffReceiver extends BroadcastReceiver {
private static final String PREF_KIOSK_MODE = "pref_kiosk_mode";
#Override
public void onReceive(Context context, Intent intent) {
if(Intent.ACTION_SCREEN_OFF.equals(intent.getAction())){
AppContext ctx = (AppContext) context.getApplicationContext();
// is Kiosk Mode active?
if(isKioskModeActive(ctx)) {
wakeUpDevice(ctx);
}
}
}
private void wakeUpDevice(AppContext context) {
PowerManager.WakeLock wakeLock = context.getWakeLock(); // get WakeLock reference via AppContext
if (wakeLock.isHeld()) {
wakeLock.release(); // release old wake lock
}
// create a new wake lock...
wakeLock.acquire();
// ... and release again
wakeLock.release();
}
private boolean isKioskModeActive(final Context context) {
SharedPreferences sp = PreferenceManager.getDefaultSharedPreferences(context);
return sp.getBoolean(PREF_KIOSK_MODE, false);
}
}
THis is Service class
public class KioskService extends Service {
private static final long INTERVAL = TimeUnit.SECONDS.toMillis(2); // periodic interval to check in seconds -> 2 seconds
private static final String TAG = KioskService.class.getSimpleName();
private static final String PREF_KIOSK_MODE = "pref_kiosk_mode";
private Thread t = null;
private Context ctx = null;
private boolean running = false;
#Override
public void onDestroy() {
Log.i(TAG, "Stopping service 'KioskService'");
running =false;
super.onDestroy();
}
#Override
public int onStartCommand(Intent intent, int flags, int startId) {
Log.i(TAG, "Starting service 'KioskService'");
running = true;
ctx = this;
// start a thread that periodically checks if your app is in the foreground
t = new Thread(new Runnable() {
#Override
public void run() {
do {
handleKioskMode();
try {
Thread.sleep(INTERVAL);
} catch (InterruptedException e) {
Log.i(TAG, "Thread interrupted: 'KioskService'");
}
}while(running);
stopSelf();
}
});
t.start();
return Service.START_NOT_STICKY;
}
private void handleKioskMode() {
// is Kiosk Mode active?
if(isKioskModeActive(ctx)) {
// is App in background?
if(isInBackground()) {
restoreApp(); // restore!
}
}
}
private boolean isInBackground() {
ActivityManager am = (ActivityManager) ctx.getSystemService(Context.ACTIVITY_SERVICE);
List<ActivityManager.RunningTaskInfo> taskInfo = am.getRunningTasks(1);
ComponentName componentInfo = taskInfo.get(0).topActivity;
return (!ctx.getApplicationContext().getPackageName().equals(componentInfo.getPackageName()));
}
private void restoreApp() {
// Restart activity
Intent i = new Intent(ctx, MainActivity.class);
i.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
ctx.startActivity(i);
}
public boolean isKioskModeActive(final Context context) {
SharedPreferences sp = PreferenceManager.getDefaultSharedPreferences(context);
return sp.getBoolean(PREF_KIOSK_MODE, false);
}
#Override
public IBinder onBind(Intent intent) {
return null;
}
}
This is my manifest
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.example.kioskmode"
android:versionCode="1"
android:versionName="1.0" >
<uses-sdk
android:minSdkVersion="8"
android:targetSdkVersion="21" />
<application
android:allowBackup="true"
android:name=".AppContext"
android:icon="#drawable/ic_launcher"
android:label="#string/app_name"
android:theme="#style/AppTheme" >
<activity
android:name=".MainActivity"
android:label="#string/app_name" >
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<service android:name="com.example.kioskmode.KioskService" android:exported="false"></service>
<receiver android:name="com.example.kioskmode.OnScreenOffReceiver" android:enabled="true" >
<intent-filter android:priority="1000" >
<action android:name="android.app.action.SCREEN_OFF" />
<action android:name="android.app.action.SCREEN_ON" />
</intent-filter>
</receiver>
</application>
<uses-permission android:name="android.permission.GET_TASKS"/>
<uses-permission android:name="android.permission.WAKE_LOCK" />
<uses-permission android:name="android.permission.READ_PHONE_STATE" />
<uses-permission android:name="android.permission.RECEIVE_BOOT_COMPLETED" />
</manifest>
Any one can solve this... for me..?? Thanks in advance..

Your method isKioskModeActive is always false. So it won't restore your app.