java - Android APP failed to redirect button after FB login -

i'm working on building app 0 knowledge... checking on tutorials old ones, 2014~ code has changed bit or lot. here problems: added login facebook button problem don't know how redirect after login process confirmed... here's code

package com.pagina.httpwww.pagina;  import android.app.activity; import android.content.intent; import android.support.v7.app.appcompatactivity; import android.os.bundle;  import android.view.view; import android.widget.button; import android.widget.textview;  import com.facebook.callbackmanager; import com.facebook.facebookcallback; import com.facebook.facebookexception; import com.facebook.facebooksdk; import com.facebook.login.loginresult; import com.facebook.login.widget.loginbutton;  public class mainactivity extends appcompatactivity implements view.onclicklistener{      loginbutton loginbutton;     textview textview;     callbackmanager callbackmanager;     button redirect;      @override     protected void oncreate(bundle savedinstancestate) {         super.oncreate(savedinstancestate);         facebooksdk.sdkinitialize(getapplicationcontext());         setcontentview(r.layout.activity_main);          /*boton redirect*/         redirect = (button)findviewbyid(r.id.botonsearch);         redirect.setonclicklistener(this);          /*login facebook*/         loginbutton = (loginbutton)findviewbyid(r.id.fb_login_bn);         textview = (textview)findviewbyid(r.id.textview);         callbackmanager = callbackmanager.factory.create();          textview.setonclicklistener(new view.onclicklistener() {             @override             public void onclick(view v) {                 intent = new intent(mainactivity.this, searchactivity.class);                 startactivity(i);             }         });          /*boton redirect*/           /*login facebook*/         class searchactivity extends activity {             @override             protected void oncreate(bundle savedinstancestate) {                 super.oncreate(savedinstancestate);                 setcontentview(r.layout.activity_search);             }         }          loginbutton.registercallback(callbackmanager, new facebookcallback<loginresult>() {             @override             public void onsuccess(loginresult loginresult) {                 loginresult.getaccesstoken().getuserid();                 loginresult.getaccesstoken().gettoken();                 textview.settext("inicio de sesión exitoso \n id: " +                     loginresult.getaccesstoken().getuserid()+                     "\n token: "+loginresult.getaccesstoken().gettoken());                 intent i=new intent(mainactivity.this, searchactivity.class);                 startactivity(i);             }              @override             public void oncancel() {                  textview.settext("inicio de sesión cancelado.");             }              @override             public void onerror(facebookexception error) {              }         });     }      @override     protected void onactivityresult(int requestcode, int resultcode, intent data) {         callbackmanager.onactivityresult(requestcode,resultcode,data);     }      @override     public void onclick(view v) {         switch (v.getid()){             case r.id.botonsearch:                 intent r = new intent(mainactivity.this, searchactivity.class);                 startactivity(r);                 break;         }     } } 

i tried build button redirect that's why added "implements view.onclicklistener" @ top public class video showed. please patient me, have 0 knowledge on this, , when explain solution remember detailed in order me understand. in advance.

ps: have mainactivity , searchactivity, in intent why have change searchactivity.class? or not? because made class redirect button, named botonredirect.java this:

import android.support.v7.app.actionbaractivity; public class botonredirect extends actionbaractivity {} 

and manifest

<activity android:name=".mainactivity">     <intent-filter>         <action android:name="android.intent.action.main" />         <category android:name="android.intent.category.launcher" />     </intent-filter> </activity>  <activity android:name=".searchactivity">     <intent-filter>         <action android:name="android.intent.action.get_content"/>         <category android:name="android.intent.category.launcher"/>     </intent-filter> </activity>  <activity android:name=".selectactivity"/> <activity android:name=".menuactivity"/> <activity android:name=".sendactivity"/> <activity android:name=".confirmactivity"/>  <meta-data     android:name="com.facebook.sdk.applicationid"     android:value="@string/facebook_app_id"/>