Emulator shows "Unfortunately app has stopped"

Question

While i'm debugging the code it shows no errors ... but while running the app it shows "Unfortunately app has stopped".this is my Activity 2 page... from this page while clicking next button it should move to Activity 3 page.this is my Activity 2 page

                     package com.example.admin.androidapp;

        import android.app.Activity;
        import android.content.Context;
        import android.content.Intent;
        import android.os.Bundle;
        import android.widget.Button;
        import android.view.View;
        import android.view.View.OnClickListener;
        import android.widget.Toast;

        public class Activity2 extends Activity  {

            Button btn11;
            Button btn22;
            public Intent intent;
            Button btn;



            @Override
            public void onCreate(Bundle savedInstanceState) {
                super.onCreate(savedInstanceState);

                setContentView(R.layout.activity_activity2);

                btn11 = (Button) findViewById(R.id.button2);
                btn22 = (Button) findViewById(R.id.button5);

                 btn = (Button) findViewById(R.id.button2);
                btn.setOnClickListener(new View.OnClickListener() {
                    @Override
                    public void onClick(View v) {
                        switch (v.getId()) {
                            case R.id.button2:
                                intent = new Intent(Activity2.this, Activity3.class);
                                startActivity(intent);
                                break;

                            case R.id.button5:
                                intent= new Intent(Activity2.this, Welcome.class);
                                startActivity(intent);
                                break;


                        }
                    }

                });

            }





        }

===============================================================

here is my Activity3 page:


    package com.example.admin.androidapp;

import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.widget.Button;
import android.widget.RadioButton;
import android.widget.RadioGroup;

    public   class Activity3 extends Activity{
    RadioGroup radiogroup;
    Button btn1;
    private Intent mIntent;

    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_activity3);

        radiogroup = (RadioGroup) findViewById(R.id.radiogroup);
        btn1 = (Button) findViewById(R.id.button);

        radiogroup.setOnCheckedChangeListener(new RadioGroup.OnCheckedChangeListener() {



@Override
        public void onCheckedChanged(RadioGroup radioGroup, int RadioID) {
                RadioButton rd = (RadioButton) radioGroup.findViewById(RadioID);


    switch (rd.getId()) {
    case R.id.radioButton7:
                       mIntent = new Intent(Activity3.this, Terminate.class);
                        break;
    case R.id.radioButton8:
                    mIntent = new Intent(Activity3.this, Activity4.class);
                    break;
    case R.id.radioButton10:
                    mIntent = new Intent(Activity3.this, Activity4.class);
                    break;
    case R.id.radioButton11:
                    mIntent = new Intent(Activity3.this, Activity4.class);
                    break;
    case R.id.radioButton15:
                    mIntent = new Intent(Activity3.this, Activity4.class);
                    break;
    case R.id.radioButton16:
                    mIntent = new Intent(Activity3.this, Activity4.class);
                    break;
    case R.id.radioButton17:
                    mIntent = new Intent(Activity3.this, Activity4.class);
                    break;
    case R.id.radioButton18:
                    mIntent = new Intent(Activity3.this, Activity4.class);
                    break;
    case R.id.radioButton19:
                    mIntent = new Intent(Activity3.this, Activity4.class);
                    break;
    case R.id.radioButton13:
                    mIntent = new Intent(Activity3.this, Activity4.class);
                    break;
    case R.id.radioButton12:
                    mIntent = new Intent(Activity3.this, Activity4.class);
                    break;
      case R.id.radioButton14:
                    mIntent = new Intent(Activity3.this, Activity4.class);
                    break;
     }
      } 
     }

========================================== Please check the above code and help me in this issue.. Thanks in advance. and im getting this message in logcat while click button like java.lang.NullPointerException: Attempt to invoke virtual method

possible duplicate of [What is a Null Pointer Exception, and how do I fix it?](http://stackoverflow.com/questions/218384/what-is-a-null-pointer-exception-and-how-do-i-fix-it) — almightyGOSU, Jun 30 '15 at 05:37
@ Android Killer .. i had declared 'btn' in activity but the same error — vinukariyad, Jun 30 '15 at 05:55
@nag my log cat shows:Attempt to invoke virtual method 'void android.widget.Button.setOnClickListener(android.view.View$OnClickListener)' on a null object reference at com.example.admin.androidapp.Activity2.onClick(Activity2.java:52) — vinukariyad, Jun 30 '15 at 05:57

Amsheer · Accepted Answer · 2015-06-30T07:22:59.067

1

The issue is you are calling onclick for btn outside of oncreate. Move the following code inside your onCreate. Also You need to initialise button

Button btn = (Button) findViewById(R.id.btn);
 btn.setOnClickListener(new View.OnClickListener() {
                    @Override
                    public void onClick(View view) {
                        if (intent != null) {
                            startActivity(intent);
                        } else {
                            Toast.makeText(getApplicationContext(), "No choice made yet", Toast.LENGTH_SHORT).show();
                        }


                    }

                });

EDIT:

Try this

btn.setOnClickListener(new View.OnClickListener() {
                        @Override
                        public void onClick(View view) {
                           Intent intent = new Intent(Activity2.this, Activity3.class);
    startActivity(intent);

                        }

                    });

You don't have initialise intent so it always null so it enters the else condition. And you add Toast there.

Toast.makeText(getApplicationContext(), "No choice made yet", Toast.LENGTH_SHORT).show();

It is showing.

edited Jun 30 '15 at 07:22

answered Jun 30 '15 at 06:07

Amsheer

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made this edits .... but....when i click next it shows "no choice made yet" and my logcat displays like " Failed sending reply to debugger: Broken pipe" – vinukariyad Jun 30 '15 at 07:17
now my first problem occurs like "unfortunately app has stopped" and my back button is working.. – vinukariyad Jun 30 '15 at 07:28
Ok then accept the answer and close. – Amsheer Jun 30 '15 at 07:32
sry its my BACK button not NEXT... i need the NEXT button to workred – vinukariyad Jun 30 '15 at 07:38
i had made some edits in my activity2... pls check my edits – vinukariyad Jun 30 '15 at 07:41
Where is the next button ? – Amsheer Jun 30 '15 at 08:46

Emulator shows "Unfortunately app has stopped"

1 Answers1