Android: How to get boolean result from AsyncTask? - android

I want to check Internet connectivity in my App. I found a code but I don't know how to use since I'm really a beginner.
My code :
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
//I want something like this.
if(InternetCheck==true){
Toast("You are connected to internet")
}
else{
Toast("Connection Failed")
}
}
static class InternetCheck extends AsyncTask<Void,Void,Boolean> {
private Consumer mConsumer;
public interface Consumer { void accept(Boolean internet); }
public InternetCheck(Consumer consumer) { mConsumer = consumer; execute(); }
#Override protected Boolean doInBackground(Void... voids) { try {
Socket sock = new Socket();
sock.connect(new InetSocketAddress("8.8.8.8", 53), 1500);
sock.close();
return true;
} catch (IOException e) { return false; } }
#Override protected void onPostExecute(Boolean internet) { mConsumer.accept(internet); }
}
But I don't know how to get a boolean result from AsyncTask. Please teach me.

new InternetCheck(new InternetCheck.Consumer() {
#Override
public void accept(Boolean connected) {
if (connected) {
Log.d("TAG", "Internet is connected");
} else {
Log.d("TAG", "Internet is not connected");
}
}
}).execute();

You can get result from AsyncTask by using get():
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Boolean result = new InternetCheck().execute().get();
if (result == true) {
Toast.makeText(this, "You are connected to internet", Toast.LENGTH_LONG).show();
} else {
Toast.makeText(this, "Connection Failed", Toast.LENGTH_LONG).show();
}
}
Or you can check boolean result in AsyncTask in onPostExecute():
#Override
protected void onPostExecute(Boolean internet) {
mConsumer.accept(internet);
if (internet == true) {
Toast.makeText(YourActivity.this, "You are connected to internet", Toast.LENGTH_LONG).show();
} else {
Toast.makeText(YourActivity.this, "Connection Failed", Toast.LENGTH_LONG).show();
}
}

Related

Flashlight function crashes after returning from activity

I have this android app which connects to an mqtt broker and listens for instructions to play/pause a ringtone or open/close the flashlight.
It runs as supposed to until i change my settings and call the function flashOnOff after this. Then i get a null pointer exception but i can not understand why.
This is my code (i did not include my imports to save some space):
public class MainActivity extends AppCompatActivity {
// Layout related parameters
Toolbar myToolbar;
Spinner mySpinner;
ImageButton flashlightButton;
Button ringtone;
EditText message;
// Camera/flashlight related parameters
Camera camera;
Camera.Parameters parameters;
// MQTT related parameters
private String BrokerIp = "tcp://192.168.1.3:1883";
private int qos = 2;
static String Username = "user1";
static String Password = "user1";
String topicStr = "commands";
String clientId = "AndroidClient";
MqttConnectOptions options;
MqttAndroidClient client;
Vibrator vibrator;
// Ringtone related parameters
Ringtone myRingtone;
MediaPlayer ringtoneMP ;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
vibrator = (Vibrator)getSystemService(VIBRATOR_SERVICE);
Uri uri = RingtoneManager.getDefaultUri(RingtoneManager.TYPE_NOTIFICATION);
myRingtone = RingtoneManager.getRingtone(getApplicationContext(),uri);
myToolbar = (Toolbar) findViewById(R.id.toolbar);
mySpinner = (Spinner) findViewById(R.id.spinner);
flashlightButton = (ImageButton) findViewById(R.id.image);
myToolbar.setLogo(R.drawable.twoguyswatchmrrobot);
myToolbar.setTitle(getResources().getString(R.string.app_name));
ArrayAdapter<String> myAdapter = new ArrayAdapter<String>(MainActivity.this,
R.layout.custom_spinner_itam,
getResources().getStringArray(R.array.Toolbar_dropdown_entries));
myAdapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
mySpinner.setAdapter(myAdapter);
ringtoneMP = MediaPlayer.create(this,R.raw.games_of_thrones);
ringtone = (Button) this.findViewById(R.id.ringtone);
message = (EditText)findViewById(R.id.messagePublish);
mySpinner.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {
#Override
public void onItemSelected(AdapterView<?> adapterView, View view, int i, long l) {
Toast.makeText(MainActivity.this,
mySpinner.getSelectedItem().toString(),
Toast.LENGTH_SHORT)
.show();
if (mySpinner.getSelectedItem().toString().equals("Exit App")){
exit();
}else if(mySpinner.getSelectedItem().toString().equals("Settings"))
{
Intent intent;
intent = new Intent(MainActivity.this, SettingsActivity.class);
intent.putExtra("CURRENT_IP",client.getServerURI());
intent.putExtra("CURRENT_QOS", Integer.toString(qos));
intent.putExtra("CURRENT_TOPIC",topicStr);
startActivityForResult(intent,1); // this is so we can take the results back to mainActivity later
}else{
System.out.println("ara3e, den exw diale3ei tipota");
}
}
#Override
public void onNothingSelected(AdapterView<?> adapterView) {
}
});
//Flashlight on Create start
if(isFlashAvailable()) // check if flash is available on this device, if it is open camera (module) and make button clickable
{
camera = Camera.open();
parameters = camera.getParameters();
}else
{ // if flashlight is not supported dont let the user click the button
flashlightButton.setEnabled(false);
AlertDialog.Builder builder = new AlertDialog.Builder(MainActivity.this);
builder.setTitle("Error.");
builder.setMessage("Flashlight not available on this device. \nExit?"); // inform the user and let him choose how to continue
builder.setPositiveButton("Yes", new DialogInterface.OnClickListener() {
#Override
public void onClick(DialogInterface dialogInterface, int i) {
dialogInterface.dismiss();
exit();
}
});
builder.setNegativeButton("Stay without flashlight", new DialogInterface.OnClickListener() {
#Override
public void onClick(DialogInterface dialogInterface, int i) {
dialogInterface.dismiss();
}
});
AlertDialog alertDialog = builder.create();
alertDialog.show();
}
flashlightButton.setOnClickListener(new View.OnClickListener() { // listen for flash button clicks
#Override
public void onClick(View view) {
flashOnOff();
}
});
ringtone.setOnClickListener(new View.OnClickListener() { // Ringtone listener
#Override
public void onClick(View view) {
ringtoneOnOff(ringtoneMP);
}
});
client = new MqttAndroidClient(MainActivity.this, BrokerIp, clientId);
// client = pahoMqttClient.getMqttClient(MainActivity.this,BrokerIp,clientId);
options = new MqttConnectOptions();
options.setUserName(Username);
options.setPassword(Password.toCharArray());
try {
IMqttToken token = client.connect(options);
token.setActionCallback(new IMqttActionListener() {
#Override
public void onSuccess(IMqttToken asyncActionToken) {
// We are connected
Toast.makeText(MainActivity.this, "connected", Toast.LENGTH_SHORT).show();
setSubscription(client,topicStr,qos);
}
#Override
public void onFailure(IMqttToken asyncActionToken, Throwable exception) {
// Something went wrong e.g. connection timeout or firewall problems
Log.w("Mqtt","Failed to connect to:"+ BrokerIp + exception.toString());
Toast.makeText(MainActivity.this, "Failed to connect to:" +exception.toString(), Toast.LENGTH_SHORT).show();
}
});
} catch (MqttException e) {
e.printStackTrace();
}
client.setCallback(new MqttCallback() {
#Override
public void connectionLost(Throwable throwable) {
Log.d("Connection:"," Lost");
}
#Override
public void messageArrived(String s, MqttMessage mqttMessage) throws Exception {
myMessageArrived(s,mqttMessage);
}
#Override
public void deliveryComplete(IMqttDeliveryToken iMqttDeliveryToken) {
Log.d("Delivery"," completed with iMqttDeliveryToken: " + iMqttDeliveryToken);
}
});
}
//Flashlight start
#Override
protected void onStop() {
super.onStop();
if(camera!=null)
{
camera.release();
camera = null;
}
}
//Flashlight end
//Backkey exit confirmation
public boolean onKeyDown(int keyCode, KeyEvent event) {
if (keyCode == KeyEvent.KEYCODE_BACK) {
exitByBackKey();
return true;
}
return super.onKeyDown(keyCode, event);
}
protected void exitByBackKey() {
AlertDialog alertbox = new AlertDialog.Builder(this)
.setMessage("Do you want to exit application?")
.setPositiveButton("Yes", new
DialogInterface.OnClickListener() {
// when yes is clicked exit the application
public void onClick(DialogInterface arg0, int arg1) {
exit();
}
})
.setNegativeButton("No", new
DialogInterface.OnClickListener() {
// when no is clicked do nothing
public void onClick(DialogInterface arg0, int arg1) {
}
})
.show();
}
//Backkey end
// PUBLISH MESSAGE
private void setSubscription(MqttAndroidClient client, String topic, int qos){
try{
client.subscribe(topic, qos);
}
catch (MqttException e){
e.printStackTrace();
}
}
private void unsetSubscription(MqttAndroidClient client,String topic){
try{
client.unsubscribe(topic);
}catch (MqttException e){
e.printStackTrace();
}
}
public void conn(View v){
try {
IMqttToken token = client.connect(options);
token.setActionCallback(new IMqttActionListener() {
#Override
public void onSuccess(IMqttToken asyncActionToken) {
// We are connected
Toast.makeText(MainActivity.this, "connected", Toast.LENGTH_SHORT).show();
setSubscription(client,topicStr,qos);
// pub();
}
#Override
public void onFailure(IMqttToken asyncActionToken, Throwable exception) {
// Something went wrong e.g. connection timeout or firewall problems
Toast.makeText(MainActivity.this, "not connected", Toast.LENGTH_SHORT).show();
}
});
} catch (MqttException e) {
e.printStackTrace();
}
}
public void disconn(View v){
if (client.isConnected()) {
try {
IMqttToken token = client.disconnect();
token.setActionCallback(new IMqttActionListener() {
#Override
public void onSuccess(IMqttToken asyncActionToken) {
// We are connected
Toast.makeText(MainActivity.this, "disconnected", Toast.LENGTH_SHORT).show();
}
#Override
public void onFailure(IMqttToken asyncActionToken, Throwable exception) {
// Something went wrong e.g. connection timeout or firewall problems
Toast.makeText(MainActivity.this, "could not disconnect", Toast.LENGTH_SHORT).show();
}
});
} catch (MqttException e) {
e.printStackTrace();
}
}else {
Toast.makeText(MainActivity.this, "Client is already disconnected", Toast.LENGTH_LONG).show();
}
}
/////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
public void pub(View v) {
String topic = topicStr;
try {
client.publish(topic, String.valueOf(message.getText()).getBytes(),qos,false);
} catch (MqttException e) {
e.printStackTrace();
}
}
private void ringtoneOnOff(MediaPlayer ringtoneMP){
if (ringtoneMP.isPlaying()){
ringtoneMP.pause();
}else{
ringtoneMP.start();
}
}
private void myMessageArrived(String s,MqttMessage mqttMessage){
if ((mqttMessage.toString()).equals("Flash on")) {
if (isFlashOn()) {
Toast.makeText(MainActivity.this, "Flashlight already on", Toast.LENGTH_SHORT).show();
} else {
Toast.makeText(MainActivity.this, "Turning flashlight on", Toast.LENGTH_SHORT).show();
flashOnOff();
}
} else if ((mqttMessage.toString()).equals("Flash off")) {
if (isFlashOn()) {
Toast.makeText(MainActivity.this, "Turning flashlight off", Toast.LENGTH_SHORT).show();
flashOnOff();
} else {
Toast.makeText(MainActivity.this, "Flashlight already off", Toast.LENGTH_SHORT).show();
}
} else if ((mqttMessage.toString()).equals("Ringtone on")) {
if (ringtoneMP.isPlaying()) {
Toast.makeText(MainActivity.this, "Ringtone already playing", Toast.LENGTH_SHORT).show();
} else {
Toast.makeText(MainActivity.this, "Playing ringtone", Toast.LENGTH_SHORT).show();
ringtoneMP.start();
}
} else if ((mqttMessage.toString()).equals("Ringtone off")) {
if (ringtoneMP.isPlaying()) {
ringtoneMP.pause();
} else {
Toast.makeText(MainActivity.this, "Ringtone already not being played", Toast.LENGTH_SHORT).show();
}
} else {
Log.d("INFO:", "This Command does not exist");
}
vibrator.vibrate(500);
myRingtone.play();
}
public void exit(){
finish();
System.exit(0);
}
public boolean isFlashAvailable(){ // boolean function that returns true if flash is supported on this device
return getApplicationContext().getPackageManager().hasSystemFeature(PackageManager.FEATURE_CAMERA_FLASH);
}
public void flashOnOff(){ // self explanatory
if (this.parameters.getFlashMode().equals(android.hardware.Camera.Parameters.FLASH_MODE_ON) || this.parameters.getFlashMode().equals(android.hardware.Camera.Parameters.FLASH_MODE_TORCH)){ // if the flash is on torch mode
Log.d("BHKE","408");
this.flashlightButton.setImageResource(R.drawable.off);
this.parameters.setFlashMode(Camera.Parameters.FLASH_MODE_OFF); // turn it off
}else{
Log.d("BHKE","412");
this.flashlightButton.setImageResource(R.drawable.on);
this.parameters.setFlashMode(Camera.Parameters.FLASH_MODE_TORCH); // else turn it on
}
this.camera.setParameters(this.parameters);
this.camera.startPreview();
}
#Override
public void onActivityResult(int requestCode, int resultCode, Intent data) {
String tempBrokerIp;
String temptopic="";
Integer tempqos;
Boolean BrokerIpChanged = true;
Boolean qosChanged = true;
Boolean topicChanged = true;
super.onActivityResult(requestCode, resultCode, data);
switch(requestCode) {
case (1) : {
if (resultCode == Activity.RESULT_OK) {
tempBrokerIp = data.getStringExtra("CURRENT_IP");
tempqos = Integer.parseInt(data.getStringExtra("CURRENT_QOS"));
temptopic = data.getStringExtra("CURRENT_TOPIC");
Log.d("Info BROKER, TOPIC, QOS", ":"+ tempBrokerIp+ " " + temptopic+ " " + tempqos);
if (tempBrokerIp.equals(BrokerIp)) {
BrokerIpChanged=false;
Log.i("BrokerIpChanged =", BrokerIpChanged.toString());
}
if (tempqos.equals(qos)) {
qosChanged=false;
Log.i("qosChanged =", qosChanged.toString());
}else {
qos = tempqos;
}
if (temptopic.equals(topicStr)){
topicChanged=false;
Log.i("topicChanged =", topicChanged.toString());
}else{
topicStr = temptopic;
}
if (!BrokerIpChanged && !qosChanged && !topicChanged) return;
if (BrokerIpChanged){
try {
client.disconnect();
BrokerIp = tempBrokerIp;
topicStr = temptopic;
qos = tempqos;
// final String clientId = MqttClient.generateClientId();
client = new MqttAndroidClient(MainActivity.this, BrokerIp, clientId);
options = new MqttConnectOptions();
options.setUserName(Username);
options.setPassword(Password.toCharArray());
// options.setMqttVersion(MqttConnectOptions.MQTT_VERSION_3_1); // to user the latest mqtt version
try {
IMqttToken token = client.connect(options);
token.setActionCallback(new IMqttActionListener() {
#Override
public void onSuccess(IMqttToken asyncActionToken) {
// We are connected
Toast.makeText(MainActivity.this, "connected", Toast.LENGTH_SHORT).show();
Log.w("Mqtt","Connected to:"+ BrokerIp);
try{
Log.v("INFO 11111:", "about to subscribe with: "+ topicStr + qos);
client.subscribe(topicStr,qos);
}catch (MqttException e){
e.printStackTrace();
}
}
#Override
public void onFailure(IMqttToken asyncActionToken, Throwable exception) {
// Something went wrong e.g. connection timeout or firewall problems
Log.w("Mqtt","Failed to connect to:"+ BrokerIp + exception.toString());
Toast.makeText(MainActivity.this, "Failed to connect to:" +exception.toString(), Toast.LENGTH_SHORT).show();
}
});
System.out.println(client.isConnected());
// if (client.isConnected()){
// Log.v("INFO 22222:", "about to subscribe with: "+ temptopic + tempqos);
// client.subscribe(temptopic,tempqos);
// }
} catch (MqttException e) {
e.printStackTrace();
}
client.setCallback(new MqttCallback() {
#Override
public void connectionLost(Throwable throwable) {
}
#Override
public void messageArrived(String s, MqttMessage mqttMessage) throws Exception {
myMessageArrived(s,mqttMessage);
}
#Override
public void deliveryComplete(IMqttDeliveryToken iMqttDeliveryToken) {
}
});
}catch (MqttException e){
e.printStackTrace();
}
}else
{
try {
client.unsubscribe(topicStr);
client.subscribe(temptopic,tempqos);
topicStr = temptopic;
qos = tempqos;
} catch (MqttException e) {
e.printStackTrace();
}
}
}
break;
}
}
}
public boolean isFlashOn(){
return (this.parameters.getFlashMode().equals(android.hardware.Camera.Parameters.FLASH_MODE_ON) || this.parameters.getFlashMode().equals(android.hardware.Camera.Parameters.FLASH_MODE_TORCH));
}
I can provide the settings activity code too is needed
It seems that the two variables needed for the flashOnOff where not initiallized after i returned from the settings activity.
Ι added :
if (isFlashAvailable()){
camera = Camera.open();
parameters = camera.getParameters();
}
at the onActivityResult start and it works like a charm.

How to Check Internet Connection using Asynctask

Hi I have been seeing tutorials and questions here in stack on how to check if the current user has a active connection to the internet. I am trying to do it myself but I have been having trouble on applying it in an AsyncTask.
I have tried it myself but I think I am doing something wrong, My knowledge in AsyncTasks are not that developed. What am I doing wrong?
Thanks in advance! :D
This is my MainActivity:
private Button checkIntrnetButton;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
checkIntrnetButton = (Button) findViewById(R.id.checkInternetButton);
checkIntrnetButton.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
if(isOnline())
{
Toast.makeText(MainActivity.this,"YOU ARE ONLINE", Toast.LENGTH_SHORT).show();
AsyncTaskRunner runner = new AsyncTaskRunner();
runner.execute();
}
else
{
Toast.makeText(MainActivity.this,"YOU ARE NOT ONLINE", Toast.LENGTH_SHORT).show();
}
}
});
}
protected boolean isOnline() {
ConnectivityManager cm = (ConnectivityManager) getSystemService(Context.CONNECTIVITY_SERVICE);
NetworkInfo netInfo = cm.getActiveNetworkInfo();
if (netInfo != null && netInfo.isConnectedOrConnecting()) {
return true;
} else {
return false;
}
}
private class AsyncTaskRunner extends AsyncTask<String, String, String> {
ProgressDialog progressDialog;
#Override
protected String doInBackground(String... params) {
if (isOnline()) {
try {
HttpURLConnection urlc = (HttpURLConnection) (new URL("http://clients3.google.com/generate_204").openConnection());
urlc.setRequestProperty("User-Agent", "Test");
urlc.setRequestProperty("Connection", "close");
urlc.setConnectTimeout(1500);
urlc.connect();
boolean url = (urlc.getResponseCode() == 200);
String str = String.valueOf(url);
return str;
} catch (IOException e) {
}
} else {
Toast.makeText(MainActivity.this, "NO CONNECTION", Toast.LENGTH_SHORT).show();
}
return null;
}
#Override
protected void onPostExecute(String result) {
// execution of result of Long time consuming operation
progressDialog.dismiss();
}
#Override
protected void onPreExecute() {
progressDialog = ProgressDialog.show(MainActivity.this,
"ProgressDialog",
"CHECKING NETWORK CONNECTION");
}
}
You should check before running the asynctask and only once, you don't need to check again inside async.
if(isOnline()) {
new AsyncTaskRunner().execute();
} else {
Toast.makeText(MainActivity.this, "NO CONNECTION", Toast.LENGTH_SHORT).show();
}
Since I am using volley for all my inserting and retrieving of data, I have been researching and experimenting about with the volley onErrorResponse. And I have found out about "NetworkError, NoConnectionError, and TimeoutError" and it help me solve the problem.
#Override
public void onErrorResponse(VolleyError error) {
if (error instanceof NetworkError) {
Toast.makeText(alcoholType.this,"THERE IS A PROBLEM WITH YOUR INTERNET CONNECTION", Toast.LENGTH_SHORT).show();
loading.dismiss();
}
else if (error instanceof NoConnectionError) {
Toast.makeText(alcoholType.this,"PLEASE SWITCH ON WIFI OR DATA", Toast.LENGTH_SHORT).show();
loading.dismiss();
}
else if (error instanceof TimeoutError) {
Toast.makeText(alcoholType.this,"Connection TimeOut! Please check your internet connection.", Toast.LENGTH_SHORT).show();
loading.dismiss();
}
}
Thanks again for everyone that helped! :D

Android service is not running in onPostExecute

I'm creating a service for my android application and I want it to run in onPostExecute on another activity.
below is CheckStatus.class (service class)
public class CheckStatus extends Service {
#Override
public int onStartCommand(Intent intent, int flags, int startId) {
Log.e("service", "start");
loop();
return START_STICKY;
}
#Override
public void onDestroy() {
super.onDestroy();
Log.e("service", "stop service");
}
private void loop(){
long endTime = System.currentTimeMillis()+5*1000;
while (System.currentTimeMillis()<endTime) {
synchronized (this) {
try {
wait(endTime - System.currentTimeMillis());
} catch (Exception e) {
}
}
}
Log.e("service", "Check status");
new CheckStatusTask().execute();
}
private class CheckStatusTask extends AsyncTask<String, Void, Void> {
char check_online;
#Override
protected Void doInBackground(String... params) {
//call url json POST method
try {
//Check return data status
} catch (Exception e) {
e.printStackTrace();
check_online = '2';
}
return null;
}
#Override
protected void onPostExecute(Void result) {
super.onPostExecute(result);
dialog.dismiss();
if (check_online == '1') {
Toast.makeText(getApplicationContext(), "online", Toast.LENGTH_SHORT).show();
} else {
Toast.makeText(getApplicationContext(), "offline", Toast.LENGTH_LONG).show();
}
}
}
}
So I try to call the service on another activity
#Override
protected void onPostExecute(Void result) {
super.onPostExecute(result);
Intent check_status = new Intent(MainActivity.this,CheckStatus.class);
startService(check_status);
}
But this is not running.
How can I make it run (the service)?
Please add following in your manifest.xml
<service
android:name=".NameOfService">
</service>

Android:How to make all activity can use socket connections

I had to establish a socket in ActivityA in normal and ready to send data,
but now I want to also be able to use the same socket connection to transmit the data in ActivityB.I have looked for information on the Internet, it seems can use the singleton.I studied for a few days, I still don't know how to start, even find some examples of exercises too, but still do not know how to use my original program.
I want to first establish between ActivityA and SERVER connection, and to pass a value to the SERVER, then press the button to switch to ActivityB, and also transmit values to SERVER
Give me some advice or teaching sites can be, so that I can continue to study it, thank you very much
Establish socket methods:
public class MainActivity extends Activity {
Button Btn_Wifi,Btn_Power,Btn_Flame;
Boolean connected=false;
Boolean powerstatus=false;
DataOutputStream dataOutputStream = null;
DataInputStream dataInputStream = null ;
Socket socket = null;
#Override
protected void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
mainView();
setListensers();
setButtonStatus();
}
private void mainView(){
Btn_Wifi = (Button) findViewById(R.id.Btn_Wifi);
Btn_Power = (Button) findViewById(R.id.Btn_Power);
Btn_Flame = (Button) findViewById(R.id.Btn_Flame);
}
private void setListensers(){
Btn_Wifi.setOnClickListener(BtnWifiOnClickListener);
Btn_Power.setOnClickListener(BtnPowerOnClickListener);
Btn_Flame.setOnClickListener(BtnFlameOnClickListener);
}
private void setButtonStatus(){
Btn_Power.setEnabled(false);
Btn_Flame.setEnabled(false);
}
Button.OnClickListener BtnWifiOnClickListener = new Button.OnClickListener(){
#Override
public void onClick(View view) {
if(!connected){
try {
socket = new Socket("IP", PORT);
dataOutputStream = new DataOutputStream(socket.getOutputStream());//and stream
changeConnectionStatus(true);//change the connection status
}catch (UnknownHostException e) {
changeConnectionStatus(false);
}catch (IOException e) {
changeConnectionStatus(false);
}
}else{
try {//try to close the socket
socket.close();
changeConnectionStatus(false);//change the connection status
} catch (UnknownHostException e) {//catch and
changeConnectionStatus(false);
} catch (IOException e) {//catch and
changeConnectionStatus(false);
}
}
}
};
Button.OnClickListener BtnPowerOnClickListener = new Button.OnClickListener(){
#Override
public void onClick(View view) {
if(!powerstatus){
try {
byte[] pon ={(byte) 0x10,(byte) 0x10};
dataOutputStream.write(pon);
dataOutputStream.flush();
PowerStatus(true);
}catch(Exception obj){
PowerStatus(false);
}
}else{
try {
byte[] poff ={(byte) 0x11,(byte) 0x11};
dataOutputStream.write(poff); //writeBytes(String str)
dataOutputStream.flush();
PowerStatus(false);
}catch(Exception obj){
PowerStatus(true);
}
PowerStatus(false);
}
}
};
Button.OnClickListener BtnFlameOnClickListener = new Button.OnClickListener(){
#Override
public void onClick(View view) {
Intent intent = new Intent();
intent.setClass(MainActivity.this, FlameActivity.class);
startActivity(intent);
}
};
public void changeConnectionStatus(Boolean isConnected) {
connected=isConnected;//change variable
if(isConnected){//if connection established
Btn_Wifi.setText("CONNECTED");
Btn_Power.setEnabled(true);
}else{
Btn_Wifi.setText("NOT WIFI");
Btn_Power.setText("POWER OFF");
Btn_Power.setEnabled(false);
PowerStatus(false);
}
}
public void PowerStatus(Boolean isPowerOn) {
powerstatus=isPowerOn;//change variable
if(isPowerOn){//if connection established
Btn_Power.setText("POWER ON");
Btn_Flame.setText("SET FLAME");
Btn_Flame.setEnabled(true);
}else{
Btn_Power.setText("POWER OFF");
Btn_Flame.setText("CANT SET FLAME");
Btn_Flame.setEnabled(false);
}
}
}
You can certainly use it by declaring,i.e: in MainActivity which creates socket connection,static YourSocketClass objSocket // which creates connection and to use it in another Activity just called it as follow i.e:MainActivity.objSocket.yourMethod(any_param). by declaring static you can access it.
public static CommunicationClient objCommunicationClient;
public boolean setConnection(final String ipAddress, final Context context,
final boolean isFromSearch) {
class EstablishConnection extends AsyncTask<Void, Void, Boolean> {
ProgressDialog objDialog;
#Override
protected void onPreExecute() {
objDialog = new ProgressDialog(context);
objDialog.setMessage(context.getResources().getString(
R.string.strConnecting));
objDialog.setProgressStyle(ProgressDialog.STYLE_SPINNER);
objDialog.show();
objDialog.setCancelable(false);
objDialog.setCanceledOnTouchOutside(false);
super.onPreExecute();
}
#Override
protected Boolean doInBackground(Void... params) {
boolean isConnected = false;
boolean isValid = false;
StrictMode.setThreadPolicy(policy);
objCommunicationClient = new CommunicationClient(ipAddress);
isSocketInitiated = objCommunicationClient.initSocket();
WifiManager wifiManager = (WifiManager) getSystemService(Context.WIFI_SERVICE);
WifiInfo info = wifiManager.getConnectionInfo();
CommonUtils.SSID = info.getSSID();
if (!isSocketInitiated) {
runOnUiThread(new Runnable() {
#Override
public void run() {
Toast.makeText(
getApplicationContext(),
getResources().getString(
R.string.strCantConnect),
Toast.LENGTH_LONG).show();
}
});
} else {
isConnected = true;
if (!isFromSearch) {
CommonUtils.IP = ipAddress;
try {
objCommunicationClient.sendRequest(context,
"<APP_SPECIFIC>");
} catch (Exception e) {
e.printStackTrace();
}
} else {
isValid = isFromSearch;
}
if (isValid) {
final Intent objIntentToGraph = new Intent(context,
GraphDataActivity.class);
objIntentToGraph
.setFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
runOnUiThread(new Runnable() {
#Override
public void run() {
startActivity(objIntentToGraph);
overridePendingTransition(
R.anim.slide_in_right,
R.anim.slide_out_left);
finish();
}
});
}
}
return isConnected;
}
#Override
protected void onPostExecute(Boolean result) {
try {
objDialog.cancel();
} catch (Exception err) {
err.printStackTrace();
}
super.onPostExecute(result);
}
}
boolean status = false;
try {
status = new EstablishConnection().execute().get();
} catch (InterruptedException e) {
e.printStackTrace();
} catch (ExecutionException e) {
e.printStackTrace();
}
return status;
}
}
// and in my other Activity i called it as
MainActivity_HomePage.objCommunicationClient.sendRequest(
context, CommonUtils.STOP_COMMAND); //send request is method which send message to server.

Create a dialogbox inside a thread while checking for an internet connection

I am trying to find out if my app is connected to the internet or not. I have a timeout set to 3 seconds. Sometimes the Internet Check will come back as "Not Connected" (even if I do have an internet connection) and sometimes it doesn't. Why does it take longer sometimes to check than others? Would I be able to have a dialogbox or something to popup while this is being checked?
public void isNetworkAvailable(final Handler handler)
{
new Thread()
{
private boolean responded = false;
#Override
public void run()
{
new Thread()
{
#Override
public void run()
{
HttpGet requestForTest = new HttpGet("http://m.google.com");
try
{
new DefaultHttpClient().execute(requestForTest);
responded = true;
}
catch (Exception e)
{
}
}
}.start();
try
{
int waited = 0;
while (!responded && (waited < 3000))
{
sleep(100);
if (!responded)
{
waited += 1000;
}
}
}
catch (InterruptedException e)
{
} // do nothing
finally
{
if (!responded)
{
handler.sendEmptyMessage(0);
}
else
{
handler.sendEmptyMessage(1);
}
}
}
}.start();
}
Handler h = new Handler()
{
#Override
public void handleMessage(Message msg)
{
if (msg.what != 1)
{ // code if not connected
Log.i("Internet check", "Not connected");
}
else
{ // code if connected
Log.i("Internet check", "Connected");
}
}
};
Use the following code
if(!haveInternet()){
<Your Alert Dialog Here>
}
private boolean haveInternet() {
NetworkInfo info = ((ConnectivityManager) getSystemService(Context.CONNECTIVITY_SERVICE))
.getActiveNetworkInfo();
if (info == null || !info.isConnected()) {
return false;
}
if (info.isRoaming()) {
return true;
}
return true;
}
are you consider use this http://developer.android.com/training/monitoring-device-state/connectivity-monitoring.html and/or register a BroadcastReceiver to notify it when connection is down/up, then you can handle it in any place of your application?
public class CustomApplication extends Application {
public static final String INTERNET_ACTION = "internet_action";
public static final String EXTRA_STATUS = "status";
#Override
public void onCreate() {
super.onCreate();
monitorNetworkAvailability();
}
private void monitorNetworkAvailability() {
//
// Improve the way to handle Thread
//
new Thread() {
private boolean responded = false;
#Override
public void run() {
while (true) {
new Thread() {
#Override
public void run() {
HttpGet requestForTest = new HttpGet("http://m.google.com");
try {
new DefaultHttpClient().execute(requestForTest);
responded = true;
} catch (Exception e) {
}
}
}.start();
try {
int waited = 0;
while (!responded && (waited < 3000)) {
sleep(100);
if (!responded) {
waited += 1000;
}
}
} catch (InterruptedException e) {
} // do nothing
finally {
Intent i = new Intent(INTERNET_ACTION);
i.putExtra(EXTRA_STATUS, responded);
sendBroadcast(i);
}
try {
Thread.sleep(1 * 60 * 1000);
} catch (InterruptedException e) {
}
}
}
}.start();
};
}
class MyActivity extends Activity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
}
#Override
protected void onResume() {
super.onResume();
registerReceiver(receiver, i);
}
#Override
protected void onPause() {
super.onPause();
unregisterReceiver(receiver);
}
IntentFilter i = new IntentFilter(CustomApplication.INTERNET_ACTION);
BroadcastReceiver receiver = new BroadcastReceiver() {
#Override
public void onReceive(Context context, Intent intent) {
boolean responded = intent.getBooleanExtra(CustomApplication.EXTRA_STATUS, false);
if (!responded) {
Toast.makeText(MyActivity.this, "No connection", Toast.LENGTH_SHORT).show();
}
}
};
}
public static Boolean isOnline(Context context) {
ConnectivityManager cm = (ConnectivityManager)context.getSystemService(Context.CONNECTIVITY_SERVICE);
NetworkInfo ni = cm.getActiveNetworkInfo();
if(ni != null && ni.isConnected())
return true;
//Toast.makeText(context, context.getString(R.string.no_internet_connection), Toast.LENGTH_SHORT).show();
return false;
}
Requires permission:
<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE"></uses-permission>
Edit:
As you correctly point out this is not a solid solution. In my case (which I indeed failed to mention) this is sufficient as a first check paired with LocationClient.isConnected().
Looking at your code I would think that it is worth taking a look at LocationClient, even if you are not planning to use location awareness of you app.
My reasoning for this is that you get rid of the need to repeatedly use resources to check if you have a valid connection. LocationClient uses the already in place communication with Google Play to tell you whether you are connected or not.
This solution of course only works if you assume that your users have a Google Account added to their device.
Here is a link to the official guidelines: http://developer.android.com/training/location/retrieve-current.html the onConnected and onDisconnected parts are found in the Define Location Services Callbacks section.
You are right. Your problem is that, the device checks for internet connection, and sometimes get a response from the router which says it cannot connect to internet, but that itself is a response, so your code might think that there is a response. Below is a sample method to test if you really can connect to the internet.
public static boolean hasActiveInternetConnection()
{
try
{
new Socket().connect(new InetSocketAddress("google.com", 80), 4000);
return true;
} catch (Exception e)
{
return false;
}
}
Then inside your activity you can call. (Make sure not to run this inside the MAIN/UI thread. Use an async or thread/handler/runnable strategy)
if(hasActiveInternetConnection())
{
//yey I have internet
}
else
{
//no internet connection
}
I was able to complete this by putting it inside an AsyncTask.
class online extends AsyncTask<String, String, String>
{
boolean responded = false;
#Override
protected void onPreExecute()
{
super.onPreExecute();
pDialog2 = new ProgressDialog(Main.this);
pDialog2.setMessage("Checking internet, please wait...");
pDialog2.setIndeterminate(false);
pDialog2.setCancelable(false);
pDialog2.show();
}
protected String doInBackground(String... args)
{
HttpGet requestForTest = new HttpGet("http://m.google.com");
try
{
new DefaultHttpClient().execute(requestForTest); // can
responded = true;
}
catch (Exception e)
{
}
try
{
int waited = 0;
while (!responded && (waited < 5000))
{
mHandler.postDelayed(new Runnable()
{
public void run()
{
}
}, 100);
waited += 100;
}
}
finally
{
if (!responded)
{
h.sendEmptyMessage(0);
}
else
{
h.sendEmptyMessage(1);
}
}
return null;
}
protected void onPostExecute(String file_url)
{
pDialog2.dismiss();
}
}

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