App crashes immediately when i run it

Question

am trying to build a basic android application with registration form appears once the application is running, it crashes when i run on the emulator this is my code

onCreate code inside main

  protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.signup);
        Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
        setSupportActionBar(toolbar);

        tv1 = (TextView) findViewById(R.id.textView1);
        tv2 = (TextView) findViewById(R.id.textView2);
        tv3 = (TextView) findViewById(R.id.textView3);

        et1 = (EditText) findViewById(R.id.email);
        et2 = (EditText) findViewById(R.id.name);
        et3 = (EditText) findViewById(R.id.password);

        submit = (Button) findViewById(R.id.register);

        submit.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {

                String email = et1.getText().toString();
                String name = et2.getText().toString();
                String password = et3.getText().toString();

                //Some code running
            }
        });

this is the console log

and here is showing that the problem is with the onClockListenr am trying to call

02-05 18:11:46.275 2121-2121/? E/AndroidRuntime: FATAL EXCEPTION: main
                                             Process: com.example.mazinalmaskari.twitter, PID: 2121
                                             java.lang.RuntimeException: Unable to start activity 

ComponentInfo{com.example.mazinalmaskari.twitter/com.example.mazinalmaskari.twitter.MainActivity}: java.lang.NullPointerException: Attempt to invoke virtual method 'void android.widget.Button.setOnClickListener(android.view.View$OnClickListener)' on a null object reference

Button attribute inside signup.xml file

<Button
    android:id="@+id/register"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_marginTop="20dp"
    android:layout_marginBottom="30dp"
    android:paddingLeft="20dp"
    android:paddingRight="20dp"
    android:layout_centerHorizontal="true"
    android:layout_below="@+id/password"
    android:text="Register"
    android:textSize="15dp"
    android:textColor="@android:color/white"/>

why is the app crashing -_-

Nothing from those LogCat lines are from your app, as far as I can tell. — CommonsWare, Feb 05 '16 at 23:12
@CommonsWare i updated it, its showing that the problem has something to do with the button — Behrouz Riahi, Feb 05 '16 at 23:16
Have you successfully run a "Hello, World!" app? I suggest starting simple and building from there. — Code-Apprentice, Feb 05 '16 at 23:16
Apparently, you do not have a widget in `R.layout.signup` named `R.id.register`. — CommonsWare, Feb 05 '16 at 23:18
The lines following what you have posted here ("FATAL EXCEPTION...") will tell you the line of code which causes the problem. Look there to start tracking down the issue. — Code-Apprentice, Feb 05 '16 at 23:19
@Code-Apprentice i built a simple application before and used buttons in it — Behrouz Riahi, Feb 05 '16 at 23:20
`submit` appears to be `null`. This means that the line with `submit = (Button) findViewById(R.id.register); ` does not return a correct reference. In order to help further, you should post the `register.xml` file. — Code-Apprentice, Feb 05 '16 at 23:21
http://stackoverflow.com/questions/6065258/how-to-interpret-logcat also provides some good tips. — Code-Apprentice, Feb 05 '16 at 23:23
@Code-Apprentice i don't have register.xml, register is the "id" of the button attribute inside signup.xml file — Behrouz Riahi, Feb 05 '16 at 23:28
I had myself confused. I deleted my comments after I figured it out. — Code-Apprentice, Feb 05 '16 at 23:29
closing because this is going nowhere. you insist on basically saying you can't have the error you have, but obviously you have. — njzk2, Feb 05 '16 at 23:31
@njzk2 am just confused, why am i having this problem, definitely am doing something wrong that i can't see, — Behrouz Riahi, Feb 05 '16 at 23:32
typically what will be asked of you is a sscce.org so people can see that the problem is in what you show, not in what you don't show. — njzk2, Feb 05 '16 at 23:41

App crashes immediately when i run it

0 Answers0