Java – button click causes the application to crash

I just set up an onclick method, which is written in the activity class and will be called as soon as I click the button Even before it enters the method, the application crashes

Error message when clicking the floating operation button;

java.lang.IllegalArgumentException: Expected receiver of type com.example.bob.vexteamqueuing.AdminControl,but got android.support.v7.view.ContextThemeWrapper java.lang.IllegalArgumentException:
Expected receiver of type com.example.bob.vexteamqueuing.AdminControl,but got android.support.v7.view.ContextThemeWrapper

at java.lang.reflect.Method.invoke(Native Method)
at android.view.View$DeclaredOnClickListener.onClick(View.java:4447)
at android.view.View.performClick(View.java:5198)
at android.view.View$PerformClick.run(View.java:21147)
at android.os.Handler.handleCallback(Handler.java:739)
at android.os.Handler.dispatchMessage(Handler.java:95)
at android.os.Looper.loop(Looper.java:148)   
at android.app.ActivityThread.main(ActivityThread.java:5417)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:726)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:616)

Active XML code:

<?xml version="1.0" encoding="utf-8"?>

<android.support.design.widget.AppBarLayout
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:theme="@style/NoActionBar">

    <android.support.v7.widget.Toolbar
        android:id="@+id/toolbar"
        android:layout_width="match_parent"
        android:layout_height="?attr/actionBarSize"
        android:background="?attr/colorPrimary"
        app:popupTheme="@style/AppTheme.PopupOverlay"
        />

</android.support.design.widget.AppBarLayout>

<include layout="@layout/content_admin_control" />

<android.support.design.widget.FloatingActionButton
    android:id="@+id/fab"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_gravity="bottom|end"
    android:layout_margin="@dimen/fab_margin"
    android:src="@android:drawable/ic_input_add"
    android:onClick="createNewTournament"
    android:clickable="true" />

Admincontrol activity java code:

public class AdminControl extends AppCompatActivity {

        Firebase ref;
        public static List <Tournament> tournaments;
        @Override
        protected void onCreate(Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);
            setContentView(R.layout.activity_admin_control);
            Toolbar b = (Toolbar) findViewById(R.id.toolbar);
            b.setTitle("Tournaments");
            setSupportActionBar(b);
            ref = AdminLogin.firebase.child("users").child(AdminLogin.firebase.getAuth().getUid());
            if (tournaments == null){
                tournaments = new ArrayList<>();
            }        
        }

        public void createNewTournament(View v) {
            Intent newIntent = new Intent(this,TournamentCreator.class);
            startActivity(newIntent);
        }  
  }

In create – tournament Creator

protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_tournament_creator);
    /*b = (FloatingActionButton) findViewById(R.id.fab);
    b.setOnClickListener(new View.OnClickListener(){
        @Override
        public void onClick(View v) {
            beginTournament(v);
        }
    });*/
}

Manifest file – may not be necessary, just provide

<?xml version="1.0" encoding="utf-8"?>

<uses-permission android:name="android.permission.INTERNET" />

<!-- To auto-complete the email text field in the login form with the user's emails -->
<uses-permission android:name="android.permission.GET_ACCOUNTS" />
<uses-permission android:name="android.permission.READ_PROFILE" />
<uses-permission android:name="android.permission.READ_CONTACTS" />

<application
    android:name=".VEXQueuing"
    android:allowBackup="true"
    android:icon="@mipmap/ic_launcher"
    android:label="@string/app_name"
    android:supportsRtl="true"
    android:theme="@style/AppTheme">
    <activity android:name=".Initial">
        <intent-filter>
            <action android:name="android.intent.action.MAIN" />

            <category android:name="android.intent.category.LAUNCHER" />
        </intent-filter>
    </activity>
    <activity
        android:name=".AdminLogin"
        android:label="@string/title_activity_admin_login"
        android:parentActivityName=".Initial">
        <Meta-data
            android:name="android.support.PARENT_ACTIVITY"
            android:value="com.example.bob.vexteamqueuing.Initial" />
    </activity>
    <activity android:name=".TournamentCreator" />
    <activity
        android:name=".AdminControl"
        android:label="@string/title_activity_admin_control"
        android:parentActivityName=".Initial"
        android:theme="@style/NoActionBar">
        <Meta-data
            android:name="android.support.PARENT_ACTIVITY"
            android:value="com.example.bob.vexteamqueuing.Initial" />
    </activity>
</application>

Solution

Your problem should be solved by removing your Android: onclick = "createnewtourname" event from your layout

<android.support.design.widget.FloatingActionButton
    android:id="@+id/fab"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_gravity="bottom|end"
    android:layout_margin="@dimen/fab_margin"
    android:src="@android:drawable/ic_input_add"   
    android:clickable="true" />

And in your oncreate for r.id Fab adds a listener, like this

protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_admin_control);
    Toolbar b = (Toolbar) findViewById(R.id.toolbar);
    b.setTitle("Tournaments");
    setSupportActionBar(b);
    ref = AdminLogin.firebase.child("users").child(AdminLogin.firebase.getAuth().getUid());
    if (tournaments == null){
        tournaments = new ArrayList<>();
    }

    FloatingActionButton myFab = (FloatingActionButton)findViewById(R.id.fab); 
    myFab.setOnClickListener(new View.OnClickListener() { 
        public void onClick(View v) { 
            createNewTournament(v); 
        } 
    });
}

The same problem occurs in EditText onclick exception and is fixed with listener

Hope this can help!!