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POAndroid NullPointerException Handling
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copied!<p>My Android application keeps crashing when i click on Fish option and nothing is inserted in the settings activity it's a null pointer exception and i tried to handle it but no result so here is my code SelectPetsScreen Acivity</p> <pre><code>package com.set.petshome; public class SelectPetsScreen extends Activity { fishtank ii=new fishtank(); ImageButton fButton,sButton,tButton; Button chButton,setsButton; private MediaPlayer mp0,mp1; public String value; final Context context = this; String numvalue; FirstSSettings testObj= new FirstSSettings(); //public String chnumber;// recipient's mobile number public String num; @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.selectscreen); //menu startup sound Code mp0=MediaPlayer.create(this,R.raw.menu); mp0.start(); //End Menu Sound Code //Settings Button Start setsButton = (Button) findViewById(R.id.settingsb); setsButton.setOnClickListener(new OnClickListener() { public void onClick(View arg0) { //Voice mp1=MediaPlayer.create(getBaseContext(),R.raw.menu); mp1.start(); //End Voice //Starting a new Intent Intent nextScreen = new Intent(getApplicationContext(), FirstSSettings.class); startActivity(nextScreen); } }); //Settings Button End //Second Ch No.Button Start chButton = (Button) findViewById(R.id.changebutton); // add button listener chButton.setOnClickListener(new OnClickListener() { @Override public void onClick(View arg0) { // custom dialog final Dialog dialog = new Dialog(context); dialog.setContentView(R.layout.mycustom); dialog.setTitle("Change Number"); // set the custom dialog components - text, image and button TextView current = (TextView) dialog.findViewById(R.id.cn); current.setText("Current Number:"); //current.setText("Current Number:"); TextView et11 = (TextView) dialog.findViewById(R.id.et1); //et11.setKeyListener(null); et11.setText(FirstSSettings.getUserNumber()); TextView newnum = (TextView) dialog.findViewById(R.id.nn); newnum.setText("New Number:"); TextView et22 = (TextView) dialog.findViewById(R.id.et2); et22.setText(""); // ImageView image = (ImageView) dialog.findViewById(R.id.image); //image.setImageResource(R.drawable.ic_launcher); Button dialogButton = (Button) dialog.findViewById(R.id.changebutton); // if button is clicked, close the custom dialog dialogButton.setOnClickListener(new OnClickListener() { @Override public void onClick(View v) { TextView et22 = (TextView) dialog.findViewById(R.id.et2); numvalue = et22.getText().toString(); FirstSSettings.setNumber(numvalue); //Button Fishtank Listener Start fButton = (ImageButton) findViewById(R.id.imageButton1); //Listening to button event fButton.setOnClickListener(new View.OnClickListener() { Boolean wifi,gsm; String x,y; public void onClick(View arg0) { num=FirstSSettings.UserNumber; //Voice mp1=MediaPlayer.create(getBaseContext(),R.raw.menu); mp1.start(); //End Voice //String s = FirstSSettings.UserGSM.toString(); //String d = FirstSSettings.UserWifi.toString(); //if(s.equals("false")&& d.equals("false")) FirstSSettings a=new FirstSSettings(); try { Log.v(FirstSSettings.UserGSM == null ? "UserGSM is Null object": "Not Null object", ""); x=FirstSSettings.UserGSM.toString(); y=FirstSSettings.UserWifi.toString(); } catch(Exception e) { Log.v("Catch NullPointerException and missed all the fun",""); e.printStackTrace(); } Log.v(x == null ? "NullPointerException after this line": "Everything is allright",""); // if();{y="false";} if(x.equals("false")&&(y.equals("false"))) { { final Dialog dialog = new Dialog(context); dialog.setContentView(R.layout.check_dialog); dialog.setTitle("Settings Alert"); TextView plCheck = (TextView) dialog.findViewById(R.id.plCheck); plCheck.setText("Check Your Connection Settings"); Button okBut = (Button) dialog.findViewById(R.id.okBut); //Temp Start // if button is clicked, close the custom dialog okBut.setOnClickListener(new OnClickListener() { @Override public void onClick(View v) { dialog.dismiss(); try { Toast.makeText(getApplicationContext(), FirstSSettings.getUserNumber(), Toast.LENGTH_SHORT).show(); } catch (Exception e) { e.printStackTrace(); } Intent nextScreen3 = new Intent(getApplicationContext(), FirstSSettings.class); startActivity(nextScreen3); } }); dialog.show(); //Temp End } else { Intent nextScreen = new Intent(getApplicationContext(), fishtank.class); startActivity(nextScreen); // Toast.makeText(getApplicationContext(), "Start", Toast.LENGTH_SHORT).show(); //Toast.makeText(getApplicationContext(), FirstSSettings.UserWifi.toString(), Toast.LENGTH_LONG).show(); //Toast.makeText(getApplicationContext(), FirstSSettings.UserGSM.toString(), Toast.LENGTH_LONG).show(); //Toast.makeText(getApplicationContext(),"End", Toast.LENGTH_SHORT).show(); } //Starting a new Intent /* testObj =new FirstSSettings(); if(testObj.getUserGSM()==false&&testObj.getUserWifi()==false) { Intent nextScreen = new Intent(getApplicationContext(), fishtank.class); startActivity(nextScreen); } else { Intent nextScreen1 = new Intent(getApplicationContext(), fishtank.class); startActivity(nextScreen1); } */ } }); //Button Fishtank Listener End //Button Cats Listener Start sButton = (ImageButton) findViewById(R.id.imageButton2); //Listening to button event sButton.setOnClickListener(new View.OnClickListener() { public void onClick(View arg0) { //Voice final MediaPlayer mp1=MediaPlayer.create(getBaseContext(),R.raw.menu); mp1.start(); //End Voice //Starting a new Intent Intent nextScreen2 = new Intent(getApplicationContext(), Csoon.class); startActivity(nextScreen2); } }); //Button Cats Listener End //Button Dogs Listener Start tButton = (ImageButton) findViewById(R.id.imageButton3); //Listening to button event tButton.setOnClickListener(new View.OnClickListener() { public void onClick(View arg0) { //Voice final MediaPlayer mp1=MediaPlayer.create(getBaseContext(),R.raw.menu); mp1.start(); //End Voice //Starting a new Intent Intent nextScreen3 = new Intent(getApplicationContext(), Dsoon.class); startActivity(nextScreen3); } });} //Button Dogs Listener End //Menu handle @Override public boolean onCreateOptionsMenu(Menu menu) { // Inflate the menu; this adds items to the action bar if it is present. getMenuInflater().inflate(R.menu.select_screen, menu); return true; } @Override public boolean onOptionsItemSelected(MenuItem item) { switch (item.getItemId()) { case R.id.ChangeColor: // write code to execute when clicked on this option Intent nextScreen3 = new Intent(getApplicationContext(), FirstSSettings.class); startActivity(nextScreen3); return true; case R.id.phoneInformation: // write code to execute when clicked on this option Intent nextScreen4 = new Intent(getApplicationContext(), Verify.class); startActivity(nextScreen4); return true; case R.id.callInfo: // startActivity(new Intent().setClass(MainActivity.this, LoginActivity.class).setData(getIntent().getData())); // write code to execute when clicked on this option return true; case R.id.email: // write code to execute when clicked on this option return true; default: return super.onOptionsItemSelected(item); } } } </code></pre> <p>FirstSSettings Activity</p> <pre><code>package com.set.petshome; public class FirstSSettings extends Activity { Button loginButton,saveButton,cancelButton; //CheckBox gsmbox,wifibox; public static Boolean UserGSM; public static Boolean UserWifi; public static String UserNumber; TextView nfield ; TextView e_num; CheckBox wifibox; CheckBox gsmbox ; TextView wifiuser,wifipass,wifi_uan,wifi_pan; String wifi_u,wifi_p; //login var EditText u,p; TextView res; String result; String x="mobile"; Thread runOnUiThread; InetAddress address; public static void setNumber(String a) { UserNumber=a; } public Boolean getUserGSM() { return UserGSM; } public Boolean getUserWifi() { return UserWifi; } public static String getUserNumber() { return UserNumber; } @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_first_ssettings); wifiuser = (TextView) findViewById(R.id.wifiuser); wifi_uan = (TextView) findViewById(R.id.wifi_uan); wifipass=(TextView) findViewById(R.id.wifipass); wifi_pan = (TextView) findViewById(R.id.wifi_pan); wifibox= (CheckBox) findViewById(R.id.Wifi); nfield = (TextView) findViewById(R.id.ntxtfield); res=(TextView)findViewById(R.id.res); nfield.setText(UserNumber); wifibox = (CheckBox) findViewById(R.id.Wifi); //Listening to button event //Wifi CheckbBox onClickListener start //Temp wifibox.setOnClickListener(new OnClickListener(){ @Override public void onClick(View v) { if (wifibox.isChecked()) { NetworkInfo xWifi; ConnectivityManager connManager = (ConnectivityManager) getSystemService(CONNECTIVITY_SERVICE); xWifi = connManager.getNetworkInfo(ConnectivityManager.TYPE_WIFI); if (xWifi.isConnected()) { // Do whatever } else { callCheck(); } }else{ } } }); //testing if it is checked or unchecked //Wifi Checkbox onClickListener end //Wifi CheckbBox onCheckedChange start wifibox.setOnCheckedChangeListener(new OnCheckedChangeListener() { //recording the click of the checkbox public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) { wifiuser = (TextView) findViewById(R.id.wifiuser); wifi_uan = (TextView) findViewById(R.id.wifi_uan); wifi_u=wifi_uan.getText().toString(); wifipass=(TextView) findViewById(R.id.wifipass); wifi_pan = (TextView) findViewById(R.id.wifi_pan); wifi_p=wifi_pan.getText().toString(); //testing if it is checked or unchecked if ( isChecked ) { //if it is check wifiuser.setVisibility(View.VISIBLE); wifi_uan.setVisibility(View.VISIBLE); wifipass.setVisibility(View.VISIBLE); wifi_pan.setVisibility(View.VISIBLE); loginButton.setVisibility(View.VISIBLE); res.setVisibility(View.VISIBLE); }else{ wifiuser.setVisibility(View.GONE); wifi_uan.setVisibility(View.GONE); wifipass.setVisibility(View.GONE); wifi_pan.setVisibility(View.GONE); loginButton.setVisibility(View.GONE); res.setVisibility(View.GONE); } } }); //Wifi CheckBox end runOnUiThread(new Runnable() { public void run() { Toast.makeText(getApplicationContext(), "Hello", Toast.LENGTH_SHORT).show(); } }); //GSM CheckbBox start gsmbox = (CheckBox) findViewById(R.id.GSM); gsmbox.setOnCheckedChangeListener(new OnCheckedChangeListener() { //recording the click of the checkbox public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) { nfield = (TextView) findViewById(R.id.ntxtfield); e_num=(TextView) findViewById(R.id.e_num); //testing if it is checked or unchecked if ( isChecked ) { //if it is check nfield.setVisibility(View.VISIBLE); e_num.setVisibility(View.VISIBLE); }else{ nfield.setVisibility(View.GONE); e_num.setVisibility(View.GONE); } } }); //GSM CheckBox end //login Button start loginButton = (Button) findViewById(R.id.login); loginButton.setOnClickListener(new OnClickListener(){ @Override public void onClick(View v) { try { wifibox= (CheckBox) findViewById(R.id.Wifi); gsmbox = (CheckBox) findViewById(R.id.GSM); UserGSM=gsmbox.isChecked(); UserWifi=wifibox.isChecked(); wifi_u=wifi_uan.getText().toString(); wifi_p=wifi_pan.getText().toString(); u = (EditText) findViewById(R.id.wifi_uan); p = (EditText) findViewById(R.id.wifi_pan); Toast.makeText(getApplicationContext(), u.getText().toString(), Toast.LENGTH_LONG).show(); Toast.makeText(getApplicationContext(), p.getText().toString(), Toast.LENGTH_LONG).show(); new MyAsyncTask().execute(u.getText().toString(),p.getText().toString()); } catch(Exception e) { e.printStackTrace(); } } }); //login Button end //Save Button Start saveButton = (Button) findViewById(R.id.save); //Temp obj saveButton.setOnClickListener(new OnClickListener() { public void onClick(View arg0) { nfield = (TextView) findViewById(R.id.ntxtfield); //wifibox= (CheckBox) findViewById(R.id.Wifi); //gsmbox = (CheckBox) findViewById(R.id.GSM); setNumber(nfield.getText().toString()); //UserGSM=gsmbox.isChecked(); //UserWifi=wifibox.isChecked(); //Starting a new Intent //wifi_u=wifi_uan.getText().toString(); //wifi_p=wifi_pan.getText().toString(); Intent nextScreen = new Intent(getApplicationContext(), SelectPetsScreen.class); startActivity(nextScreen); //setDefaults(); try { Toast.makeText(getApplicationContext(), UserNumber, Toast.LENGTH_SHORT).show(); Toast.makeText(getApplicationContext(), UserGSM.toString(), Toast.LENGTH_SHORT).show(); Toast.makeText(getApplicationContext(), UserWifi.toString(), Toast.LENGTH_SHORT).show(); } catch (Exception e) { e.printStackTrace(); } } }); //Save button End //Cancel button Start cancelButton = (Button) findViewById(R.id.cancel); cancelButton.setOnClickListener(new OnClickListener() { public void onClick(View arg0) { //Starting a new Intent Intent nextScreen2 = new Intent(getApplicationContext(), SelectPetsScreen.class); startActivity(nextScreen2); } }); //Cancel Button End } } </code></pre> <p>Logcat</p> <pre><code> 12-04 21:04:05.041: E/AndroidRuntime(2789): FATAL EXCEPTION: main 12-04 21:04:05.041: E/AndroidRuntime(2789): java.lang.NullPointerException 12-04 21:04:05.041: E/AndroidRuntime(2789): at com.set.petshome.SelectPetsScreen$4.onClick(SelectPetsScreen.java:211) 12-04 21:04:05.041: E/AndroidRuntime(2789): at android.view.View.performClick(View.java:4240) 12-04 21:04:05.041: E/AndroidRuntime(2789): at android.view.View$PerformClick.run(View.java:17721) 12-04 21:04:05.041: E/AndroidRuntime(2789): at android.os.Handler.handleCallback(Handler.java:730) 12-04 21:04:05.041: E/AndroidRuntime(2789): at android.os.Handler.dispatchMessage(Handler.java:92) 12-04 21:04:05.041: E/AndroidRuntime(2789): at android.os.Looper.loop(Looper.java:137) 12-04 21:04:05.041: E/AndroidRuntime(2789): at android.app.ActivityThread.main(ActivityThread.java:5103) 12-04 21:04:05.041: E/AndroidRuntime(2789): at java.lang.reflect.Method.invokeNative(Native Method) 12-04 21:04:05.041: E/AndroidRuntime(2789): at java.lang.reflect.Method.invoke(Method.java:525) 12-04 21:04:05.041: E/AndroidRuntime(2789): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:737) 12-04 21:04:05.041: E/AndroidRuntime(2789): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:553) 12-04 21:04:05.041: E/AndroidRuntime(2789): at dalvik.system.NativeStart.main(Native Method) </code></pre>

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