android - App fails after launch since trying to implement a checkbox -

at place work have samsung tablets run in kiosk mode.

sadly there bug hardware means if battery gets low loose data , time , can't connect wifi, created simple app in android studio utilizing "logon activity" template settings , correct time issue.

that works well, though able use app settings mdm system.

so tried adding checkbox , if statement "if checked x else y" since doing app won't run.

i've tried looking @ various tutorials , adapting them achieve though far have had no luck.

my code below if amazing.

ps : i'm not android developer , i'am picking bits google. have lot learn sorry if missed simple.

loginactivity.java

package mypackagename;  import android.animation.animator; import android.animation.animatorlisteneradapter; import android.annotation.targetapi; import android.content.intent; import android.content.pm.packagemanager; import android.support.annotation.nonnull; import android.support.design.widget.snackbar; import android.support.v7.app.appcompatactivity; import android.app.loadermanager.loadercallbacks;  import android.content.cursorloader; import android.content.loader; import android.database.cursor; import android.net.uri; import android.os.asynctask;  import android.os.build; import android.os.bundle; import android.provider.contactscontract; import android.text.textutils; import android.view.keyevent; import android.view.view; import android.view.view.onclicklistener; import android.view.inputmethod.editorinfo; import android.widget.arrayadapter; import android.widget.autocompletetextview; import android.widget.button; import android.widget.edittext; import android.widget.textview; import android.widget.checkbox; import android.widget.toast;   import java.util.arraylist; import java.util.list;  import android.content.context; import android.telephony.telephonymanager;  import static android.manifest.permission.read_contacts;    /**  * login screen offers login via email/password.  */  public class loginactivity extends appcompatactivity implements loadercallbacks<cursor> {      telephonymanager tel;     textview imei;        /**      * id identity read_contacts permission request.      */     private static final int request_read_contacts = 0;      /**      * dummy authentication store containing known user names , passwords.      * todo: remove after connecting real authentication system.      */     private static final string[] dummy_credentials = new string[]{             "user@domain.domain:password"     };     /**      * keep track of login task ensure can cancel if requested.      */     private userlogintask mauthtask = null;      // ui references.     private autocompletetextview memailview;     private edittext mpasswordview;     private view mprogressview;     private view mloginformview;     private checkbox cb1;       @override     protected void oncreate(bundle savedinstancestate) {           super.oncreate(savedinstancestate);         setcontentview(r.layout.activity_login);         // set login form.         memailview = (autocompletetextview) findviewbyid(r.id.email);         populateautocomplete();          mpasswordview = (edittext) findviewbyid(r.id.password);         mpasswordview.setoneditoractionlistener(new textview.oneditoractionlistener() {             @override             public boolean oneditoraction(textview textview, int id, keyevent keyevent) {                 if (id == r.id.login || id == editorinfo.ime_null) {                     attemptlogin();                     return true;                 }                 return false;             }         });          button memailsigninbutton = (button) findviewbyid(r.id.email_sign_in_button);         memailsigninbutton.setonclicklistener(new onclicklistener() {             @override             public void onclick(view view) {                 attemptlogin();             }         });          mloginformview = findviewbyid(r.id.login_form);         mprogressview = findviewbyid(r.id.login_progress);          tel = (telephonymanager) getsystemservice(context.telephony_service);          imei = (textview) findviewbyid(r.id.textview2);         imei.settext(tel.getdeviceid().tostring());          super.oncreate(savedinstancestate);         setcontentview(r.layout.activity_login);      }       private void populateautocomplete() {         if (!mayrequestcontacts()) {             return;         }          getloadermanager().initloader(0, null, this);     }      private boolean mayrequestcontacts() {         if (build.version.sdk_int < build.version_codes.m) {             return true;         }         if (checkselfpermission(read_contacts) == packagemanager.permission_granted) {             return true;         }         if (shouldshowrequestpermissionrationale(read_contacts)) {             snackbar.make(memailview, r.string.permission_rationale, snackbar.length_indefinite)                     .setaction(android.r.string.ok, new view.onclicklistener() {                         @override                         @targetapi(build.version_codes.m)                         public void onclick(view v) {                             requestpermissions(new string[]{read_contacts}, request_read_contacts);                         }                     });         } else {             requestpermissions(new string[]{read_contacts}, request_read_contacts);         }         return false;     }      /**      * callback received when permissions request has been completed.      */     @override     public void onrequestpermissionsresult(int requestcode, @nonnull string[] permissions,                                            @nonnull int[] grantresults) {         if (requestcode == request_read_contacts) {             if (grantresults.length == 1 && grantresults[0] == packagemanager.permission_granted) {                 populateautocomplete();             }         }     }       /**      * attempts sign in or register account specified login form.      * if there form errors (invalid email, missing fields, etc.),      * errors presented , no actual login attempt made.      */     private void attemptlogin() {         if (mauthtask != null) {             return;         }          // reset errors.         memailview.seterror(null);         mpasswordview.seterror(null);          // store values @ time of login attempt.         string email = memailview.gettext().tostring();         string password = mpasswordview.gettext().tostring();          boolean cancel = false;         view focusview = null;          // check valid password, if user entered one.         if (!textutils.isempty(password) && !ispasswordvalid(password)) {             mpasswordview.seterror(getstring(r.string.error_invalid_password));             focusview = mpasswordview;             cancel = true;         }          // check valid email address.         if (textutils.isempty(email)) {             memailview.seterror(getstring(r.string.error_field_required));             focusview = memailview;             cancel = true;         } else if (!isemailvalid(email)) {             memailview.seterror(getstring(r.string.error_invalid_email));             focusview = memailview;             cancel = true;         }          if (cancel) {             // there error; don't attempt login , focus first             // form field error.             focusview.requestfocus();         } else {             // show progress spinner, , kick off background task             // perform user login attempt.             showprogress(true);             mauthtask = new userlogintask(email, password);             mauthtask.execute((void) null);           }     }      private boolean isemailvalid(string email) {         //todo: replace own logic         return email.contains("@");     }      private boolean ispasswordvalid(string password) {         //todo: replace own logic         return password.length() > 4;     }      /**      * shows progress ui , hides login form.      */     @targetapi(build.version_codes.honeycomb_mr2)     private void showprogress(final boolean show) {         // on honeycomb mr2 have viewpropertyanimator apis, allow         // easy animations. if available, use these apis fade-in         // progress spinner.         if (build.version.sdk_int >= build.version_codes.honeycomb_mr2) {             int shortanimtime = getresources().getinteger(android.r.integer.config_shortanimtime);              mloginformview.setvisibility(show ? view.gone : view.visible);             mloginformview.animate().setduration(shortanimtime).alpha(                     show ? 0 : 1).setlistener(new animatorlisteneradapter() {                 @override                 public void onanimationend(animator animation) {                     mloginformview.setvisibility(show ? view.gone : view.visible);                 }             });              mprogressview.setvisibility(show ? view.visible : view.gone);             mprogressview.animate().setduration(shortanimtime).alpha(                     show ? 1 : 0).setlistener(new animatorlisteneradapter() {                 @override                 public void onanimationend(animator animation) {                     mprogressview.setvisibility(show ? view.visible : view.gone);                 }             });         } else {             // viewpropertyanimator apis not available, show             // , hide relevant ui components.             mprogressview.setvisibility(show ? view.visible : view.gone);             mloginformview.setvisibility(show ? view.gone : view.visible);         }     }      @override     public loader<cursor> oncreateloader(int i, bundle bundle) {         return new cursorloader(this,                 // retrieve data rows device user's 'profile' contact.                 uri.withappendedpath(contactscontract.profile.content_uri,                         contactscontract.contacts.data.content_directory), profilequery.projection,                  // select email addresses.                 contactscontract.contacts.data.mimetype +                         " = ?", new string[]{contactscontract.commondatakinds.email                 .content_item_type},                  // show primary email addresses first. note there won't                 // primary email address if user hasn't specified one.                 contactscontract.contacts.data.is_primary + " desc");     }      @override     public void onloadfinished(loader<cursor> cursorloader, cursor cursor) {         list<string> emails = new arraylist<>();         cursor.movetofirst();         while (!cursor.isafterlast()) {             emails.add(cursor.getstring(profilequery.address));             cursor.movetonext();         }          addemailstoautocomplete(emails);     }      @override     public void onloaderreset(loader<cursor> cursorloader) {      }      private void addemailstoautocomplete(list<string> emailaddresscollection) {         //create adapter tell autocompletetextview show in dropdown list.         arrayadapter<string> adapter =                 new arrayadapter<>(loginactivity.this,                         android.r.layout.simple_dropdown_item_1line, emailaddresscollection);          memailview.setadapter(adapter);     }       private interface profilequery {         string[] projection = {                 contactscontract.commondatakinds.email.address,                 contactscontract.commondatakinds.email.is_primary,         };          int address = 0;         int is_primary = 1;     }      /**      * represents asynchronous login/registration task used authenticate      * user.      */      public class userlogintask extends asynctask<void, void, boolean> {          private final string memail;         private final string mpassword;          userlogintask(string email, string password) {             memail = email;             mpassword = password;         }          @override         protected boolean doinbackground(void... params) {             // todo: attempt authentication against network service.             try {                 // simulate network access.                thread.sleep(2000);             } catch (interruptedexception e) {                return false;             }              (string credential : dummy_credentials) {                 string[] pieces = credential.split(":");                 if (pieces[0].equals(memail)) { //                    // account exists, return true if password matches.                     return pieces[1].equals(mpassword);                 }             }              // todo: register new account here.             return false;        }          @override         protected void onpostexecute(final boolean success) {             mauthtask = null;             showprogress(false); //success below             if (success) {   //initiate check box                 checkbox cb1 = (checkbox) findviewbyid(r.id.cb1); //check current state of check box (true or false)                 boolean checkboxstate = cb1.ischecked();                  if(cb1.ischecked()) {                     intent = getpackagemanager().getlaunchintentforpackage("com.mobileiron");                     i.addflags(intent.flag_activity_new_task);                     i.setpackage("com.mobileiron");                     i.setpackage(null);                     startactivity(i);                     finish();                  }                 else {                 intent = new intent(android.provider.settings.action_date_settings);                 i.addflags(intent.flag_activity_new_task);                 i.setpackage("android.provider.settings.action_date_settings");                 i.setpackage(null);                 startactivity(i);                 finish();              }               } else {                 mpasswordview.seterror(getstring(r.string.error_incorrect_password));                 mpasswordview.requestfocus();             }         }          @override         protected void oncancelled() {             mauthtask = null;             showprogress(false);          }     } } </i>`  

checkbox activity_login.xml

<checkbox         android:text="@string/cb1"         android:layout_width="328dp"         android:layout_height="wrap_content"         android:id="@+id/cb1"         android:onclick="oncheckboxclicked"         android:checked="false" /> 

your oncheckboxclicked method onclick of checkbox not found in activity.