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ProgressBar Null Point Exception making the application crash [closed]

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I am new to Android Application Development and while working on a project. I receive the following error and I can't seem to figure out the solution and it makes my application crash.
I have a application which is conneting to firebase and registering user and saving its details to the database. But when I am opening the register user activity the app crashed and hence doesn't proceed further. Please help as I am quite new to android app development.
The logcat is here
2020-05-27 01:08:00.427 25788-25788/com.example.auth E/AndroidRuntime: FATAL EXCEPTION: main
Process: com.example.auth, PID: 25788
java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.auth/com.example.auth.RegisterActivity}: java.lang.NullPointerException: Attempt to invoke virtual method 'void android.widget.ProgressBar.setVisibility(int)' on a null object reference
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2913)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:3048)
at android.app.servertransaction.LaunchActivityItem.execute(LaunchActivityItem.java:78)
at android.app.servertransaction.TransactionExecutor.executeCallbacks(TransactionExecutor.java:108)
at android.app.servertransaction.TransactionExecutor.execute(TransactionExecutor.java:68)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1808)
at android.os.Handler.dispatchMessage(Handler.java:106)
at android.os.Looper.loop(Looper.java:193)
at android.app.ActivityThread.main(ActivityThread.java:6669)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:493)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:858)
Caused by: java.lang.NullPointerException: Attempt to invoke virtual method 'void android.widget.ProgressBar.setVisibility(int)' on a null object reference
at com.example.auth.RegisterActivity.onCreate(RegisterActivity.java:35)
at android.app.Activity.performCreate(Activity.java:7136)
at android.app.Activity.performCreate(Activity.java:7127)
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1271)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2893)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:3048) 
at android.app.servertransaction.LaunchActivityItem.execute(LaunchActivityItem.java:78) 
at android.app.servertransaction.TransactionExecutor.executeCallbacks(TransactionExecutor.java:108) 
at android.app.servertransaction.TransactionExecutor.execute(TransactionExecutor.java:68) 
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1808) 
at android.os.Handler.dispatchMessage(Handler.java:106) 
at android.os.Looper.loop(Looper.java:193) 
at android.app.ActivityThread.main(ActivityThread.java:6669) 
at java.lang.reflect.Method.invoke(Native Method) 
at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:493) 
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:858) 
2020-05-27 01:08:00.452 25788-25788/com.example.auth I/Process: Sending signal. PID: 25788 SIG: 9
Here is the RegisterActivity.java
package com.example.auth;
import androidx.annotation.NonNull;
import androidx.appcompat.app.AppCompatActivity;
import android.os.Bundle;
import android.util.Patterns;
import android.view.View;
import android.widget.EditText;
import android.widget.ProgressBar;
import android.widget.Toast;
import com.google.android.gms.tasks.OnCompleteListener;
import com.google.android.gms.tasks.Task;
import com.google.firebase.auth.AuthResult;
import com.google.firebase.auth.FirebaseAuth;
import com.google.firebase.database.FirebaseDatabase;
public class RegisterActivity extends AppCompatActivity implements View.OnClickListener {
private EditText editTextName, editTextEmail, editTextPassword, editTextPhone;
private ProgressBar progressBar;
private FirebaseAuth mAuth;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
editTextName = findViewById(R.id.edit_text_name);
editTextEmail = findViewById(R.id.edit_text_email);
editTextPassword = findViewById(R.id.edit_text_password);
editTextPhone = findViewById(R.id.edit_text_phone);
progressBar = (ProgressBar) findViewById(R.id.progressbar);
**progressBar.setVisibility(View.GONE);**
mAuth = FirebaseAuth.getInstance();
findViewById(R.id.button_register).setOnClickListener(this);
}
#Override
protected void onStart() {
super.onStart();
if (mAuth.getCurrentUser() != null) {
//handle the already login user
}
}
private void registerUser() {
final String name = editTextName.getText().toString().trim();
final String email = editTextEmail.getText().toString().trim();
String password = editTextPassword.getText().toString().trim();
final String phone = editTextPhone.getText().toString().trim();
if (name.isEmpty()) {
editTextName.setError(getString(R.string.input_error_name));
editTextName.requestFocus();
return;
}
if (email.isEmpty()) {
editTextEmail.setError(getString(R.string.input_error_email));
editTextEmail.requestFocus();
return;
}
if (!Patterns.EMAIL_ADDRESS.matcher(email).matches()) {
editTextEmail.setError(getString(R.string.input_error_email_invalid));
editTextEmail.requestFocus();
return;
}
if (password.isEmpty()) {
editTextPassword.setError(getString(R.string.input_error_password));
editTextPassword.requestFocus();
return;
}
if (password.length() < 6) {
editTextPassword.setError(getString(R.string.input_error_password_length));
editTextPassword.requestFocus();
return;
}
if (phone.isEmpty()) {
editTextPhone.setError(getString(R.string.input_error_phone));
editTextPhone.requestFocus();
return;
}
if (phone.length() != 10) {
editTextPhone.setError(getString(R.string.input_error_phone_invalid));
editTextPhone.requestFocus();
return;
}
progressBar.setVisibility(View.VISIBLE);
mAuth.createUserWithEmailAndPassword(email, password)
.addOnCompleteListener(new OnCompleteListener<AuthResult>() {
#Override
public void onComplete(#NonNull Task<AuthResult> task) {
if (task.isSuccessful()) {
User user = new User(
name,
email,
phone
);
FirebaseDatabase.getInstance().getReference("Users")
.child(FirebaseAuth.getInstance().getCurrentUser().getUid())
.setValue(user).addOnCompleteListener(new OnCompleteListener<Void>() {
#Override
public void onComplete(#NonNull Task<Void> task) {
progressBar.setVisibility(View.GONE);
if (task.isSuccessful()) {
Toast.makeText(RegisterActivity.this, getString(R.string.registration_success), Toast.LENGTH_LONG).show();
} else {
//display a failure message
}
}
});
} else {
Toast.makeText(RegisterActivity.this, task.getException().getMessage(), Toast.LENGTH_LONG).show();
}
}
});
}
#Override
public void onClick(View v) {
switch (v.getId()) {
case R.id.button_register:
registerUser();
break;
}
}
}
Here is activity_register.xml
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context="com.example.auth.RegisterActivity">
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_centerVertical="true"
android:orientation="vertical"
android:padding="#dimen/default_padding">
<TextView
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:fontFamily="cursive"
android:text="#string/app_name"
android:textAlignment="center"
android:textColor="#color/colorText"
android:textSize="#dimen/app_name_size" />
<EditText
android:id="#+id/edit_text_name"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:drawableLeft="#drawable/ic_name"
android:drawablePadding="#dimen/drawable_padding"
android:hint="#string/full_name"
android:nextFocusDown="#id/edit_text_email"
android:textColor="#color/colorText"
android:textColorHint="#color/colorHint" />
<EditText
android:id="#+id/edit_text_email"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:drawableLeft="#drawable/ic_email"
android:drawablePadding="#dimen/drawable_padding"
android:hint="#string/email"
android:inputType="textEmailAddress"
android:nextFocusDown="#id/edit_text_password"
android:textColor="#color/colorText"
android:textColorHint="#color/colorHint" />
<EditText
android:id="#+id/edit_text_password"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:drawableLeft="#drawable/ic_password"
android:drawablePadding="#dimen/drawable_padding"
android:hint="#string/password"
android:inputType="textPassword"
android:nextFocusDown="#id/edit_text_phone"
android:textColor="#color/colorText"
android:textColorHint="#color/colorHint" />
<EditText
android:id="#+id/edit_text_phone"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:digits="0123456789"
android:drawableLeft="#drawable/ic_phone"
android:drawablePadding="#dimen/drawable_padding"
android:hint="#string/phone"
android:inputType="number"
android:maxLength="10"
android:nextFocusDown="#id/button_register"
android:textColor="#color/colorText"
android:textColorHint="#color/colorHint" />
<RadioGroup
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:checkedButton="#id/radioButton1"
android:orientation="horizontal">
<RadioButton
android:id="#+id/radioButton1"
android:layout_width="118dp"
android:layout_height="wrap_content"
android:text="Student" />
<RadioButton
android:id="#+id/radioButton2"
android:layout_width="135dp"
android:layout_height="wrap_content"
android:text="Institute" />
<RadioButton
android:id="#+id/radioButton3"
android:layout_width="267dp"
android:layout_height="wrap_content"
android:text="Teacher" />
</RadioGroup>
<Button
android:id="#+id/button_register"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:background="#drawable/bg_button_register"
android:text="#string/register"
android:textAllCaps="false"
android:textColor="#color/colorText" />
</LinearLayout>
<ProgressBar
android:id="#+id/progressbar"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_centerHorizontal="true"
android:layout_centerVertical="true" />
</RelativeLayout>

This is a typo:
setContentView(R.layout.activity_main);
but your layout is actually activity_register, not activity_main.
You probably meant:
setContentView(R.layout.activity_register);

The error message:
java.lang.NullPointerException: Attempt to invoke virtual method 'void android.widget.ProgressBar.setVisibility(int)' on a null object reference
Is telling you that progressBar is null. You can't call methods on a null object. It's null because findViewById couldn't find a view with the given ID. You will have to examine your inflated. layout to figure out why that is.

Seems like you are setting the wrong layout in:
setContentView(R.layout.activity_main);
But you posted activity_register.xml
You should do something like:
setContentView(R.layout.activity_register);
If you try to invoke any method on any of your editTexts, you should get an NPE there as well.

Clicking register causes android app to crash

Clicking on register makes the app crash when the email and password fields are empty, but when the name field is empty it works properly what seems to be the problem?
xml file:
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:gravity="center_vertical|center_horizontal"
android:orientation="vertical"
android:paddingBottom="#dimen/activity_vertical_margin"
android:paddingLeft="#dimen/activity_horizontal_margin"
android:paddingRight="#dimen/activity_horizontal_margin"
android:paddingTop="#dimen/activity_vertical_margin"
tools:context="com.example.zachmarcelo.softcash.LoginActivity"
android:background="#fff"
>
<!-- Login progress -->
<ImageView
android:layout_width="match_parent"
android:layout_height="47dp"
android:layout_marginBottom="20dp"
android:visibility="visible"
app:srcCompat="#drawable/icon_ewallet_" />
<ProgressBar
android:id="#+id/login_progress"
style="?android:attr/progressBarStyleLarge"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginBottom="8dp"
android:visibility="gone" />
<ScrollView
android:id="#+id/login_form"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_gravity="center">
<LinearLayout
android:id="#+id/email_login_form"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:gravity="center_vertical|center_horizontal"
android:orientation="vertical">
<android.support.design.widget.TextInputLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:textColorHint="#color/colorHint" >
<EditText
android:id="#+id/reg_username"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:hint="Name"
android:inputType="text"
android:textSize="20sp"
android:textColor="#android:color/background_dark"
/>
</android.support.design.widget.TextInputLayout>
<android.support.design.widget.TextInputLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:theme="#style/TextLabel"
android:textColorHint="#color/colorHint">
<EditText
android:id="#+id/reg_email"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:backgroundTint="#android:color/darker_gray"
android:hint="Email"
android:maxLines="1"
android:singleLine="true"
android:textColor="#android:color/background_dark"
android:inputType="textEmailAddress"
/>
</android.support.design.widget.TextInputLayout>
<android.support.design.widget.TextInputLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:theme="#style/TextLabel"
android:textColorHint="#color/colorHint">
<EditText
android:id="#+id/reg_password"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:backgroundTint="#android:color/background_dark"
android:hint="Password"
android:imeActionId="6"
android:imeActionLabel="#string/action_sign_in_short"
android:imeOptions="actionUnspecified"
android:inputType="textPassword"
android:maxLines="1"
android:singleLine="true"
android:textColor="#android:color/background_dark" />
</android.support.design.widget.TextInputLayout>
<Button
android:id="#+id/register"
style="?android:textAppearanceSmall"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginTop="16dp"
android:background="#color/colorAccent"
android:gravity="center"
android:paddingLeft="20sp"
android:paddingRight="20sp"
android:text="Register"
android:textStyle="bold"
android:layout_marginBottom="20dp"/>
<TextView
android:id="#+id/signin"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:gravity="center"
android:text="Already have an account?"
android:textAlignment="center"
android:textColor="#color/colorPrimary"
android:textSize="12dp" />
</LinearLayout>
</ScrollView>
<ProgressBar
android:id="#+id/progressBar"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_centerHorizontal="true"
android:layout_centerVertical="true" />
code:
package com.example.zachmarcelo.softcash;
import android.content.Intent;
import android.os.Bundle;
import android.support.annotation.NonNull;
import android.support.annotation.Nullable;
import android.support.design.widget.TextInputEditText;
import android.support.v7.app.AppCompatActivity;
import android.util.Log;
import android.util.Patterns;
import android.view.View;
import android.view.WindowManager;
import android.widget.AutoCompleteTextView;
import android.widget.EditText;
import android.widget.ProgressBar;
import android.widget.Toast;
import com.google.android.gms.tasks.OnCompleteListener;
import com.google.android.gms.tasks.Task;
import com.google.firebase.auth.AuthResult;
import com.google.firebase.auth.FirebaseAuth;
import com.google.firebase.database.FirebaseDatabase;
public class RegisterActivity extends AppCompatActivity implements
View.OnClickListener {
private EditText reg_password,
reg_username,
reg_email;
private FirebaseAuth mAuth;
private ProgressBar progressBar;
#Override
protected void onCreate(#Nullable Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_register);
progressBar = new ProgressBar(getApplicationContext());
reg_password = findViewById(R.id.reg_password);
reg_email = findViewById(R.id.reg_email);
reg_username = findViewById(R.id.reg_username);
progressBar = findViewById(R.id.progressBar);
progressBar.setVisibility(View.GONE);
mAuth = FirebaseAuth.getInstance();
findViewById(R.id.register).setOnClickListener(this);
findViewById(R.id.signin).setOnClickListener(this);
}
#Override
protected void onStart() {
super.onStart();
if (mAuth.getCurrentUser() != null) {
Intent i = new Intent(RegisterActivity.this, HomeActivity.class);
startActivity(i);
finish();
}
}
private void registerUser() {
final String username = reg_username.getText().toString().trim();
final String email = reg_email.getText().toString().trim();
String password = reg_password.getText().toString().trim();
if (username.equals("")) {
reg_username.setError(getString(R.string.input_error_name));
reg_username.requestFocus();
return;
}
if (email.equals("")) {
reg_email.setError(getString(R.string.input_error_email));
reg_email.requestFocus();
return;
}else{
if (!Patterns.EMAIL_ADDRESS.matcher(email).matches()) {
reg_email.setError(getString(R.string.input_error_email_invalid));
reg_email.requestFocus();
return;
}
}
if (password.equals("")) {
reg_password.setError(getString(R.string.input_error_password));
reg_password.requestFocus();
return;
}else{
if (password.length() < 8) {
reg_password.setError(getString(R.string.input_error_password_length));
reg_password.requestFocus();
return;
}
}
progressBar.setVisibility(View.VISIBLE);
getWindow().setFlags(WindowManager.LayoutParams.FLAG_NOT_TOUCHABLE,
WindowManager.LayoutParams.FLAG_NOT_TOUCHABLE);
mAuth.createUserWithEmailAndPassword(email, password)
.addOnCompleteListener(new OnCompleteListener<AuthResult>() {
#Override
public void onComplete(#NonNull Task<AuthResult> task) {
if (task.isSuccessful()) {
User user = new User(
username,
email
);
FirebaseDatabase.getInstance().getReference("Users")
.child(FirebaseAuth.getInstance().getCurrentUser().getUid())
.setValue(user).addOnCompleteListener(new OnCompleteListener<Void>() {
#Override
public void onComplete(#NonNull Task<Void> task) {
progressBar.setVisibility(View.GONE);
getWindow().clearFlags(WindowManager.LayoutParams.FLAG_NOT_TOUCHABLE);
if (task.isSuccessful()) {
Toast.makeText(RegisterActivity.this, getString(R.string.registration_success), Toast.LENGTH_LONG).show();
Intent i = new Intent(RegisterActivity.this, LoginActivity.class);
startActivity(i);
finish();
} else {
Toast.makeText(RegisterActivity.this, getString(R.string.registration_failed), Toast.LENGTH_LONG).show();
}
}
});
} else {
Toast.makeText(RegisterActivity.this, task.getException().getMessage(), Toast.LENGTH_LONG).show();
}
}
});
}
#Override
public void onClick(View view) {
switch (view.getId()){
case R.id.register:
registerUser();
break;
case R.id.signin:
Intent i = new Intent(this, LoginActivity.class);
startActivity(i);
finish();
break;
}
}
}
error log:
09-03 13:25:24.942 15875-15875/com.example.zachmarcelo.softcash E/AndroidRuntime: FATAL EXCEPTION: main
Process: com.example.zachmarcelo.softcash, PID: 15875
android.view.InflateException: Binary XML file line #17: Binary XML file line #17: Error inflating class TextView
Caused by: android.view.InflateException: Binary XML file line #17: Error inflating class TextView
Caused by: java.lang.UnsupportedOperationException: Failed to resolve attribute at index 4: TypedValue{t=0x2/d=0x1010099 a=1}
at android.content.res.TypedArray.getColor(TypedArray.java:492)
at android.widget.TextView.<init>(TextView.java:955)
at android.widget.TextView.<init>(TextView.java:872)
at android.support.v7.widget.AppCompatTextView.<init>(AppCompatTextView.java:75)
at android.support.v7.widget.AppCompatTextView.<init>(AppCompatTextView.java:71)
at android.support.v7.app.AppCompatViewInflater.createView(AppCompatViewInflater.java:103)
at android.support.v7.app.AppCompatDelegateImplV9.createView(AppCompatDelegateImplV9.java:1024)
at android.support.v7.app.AppCompatDelegateImplV9.onCreateView(AppCompatDelegateImplV9.java:1081)
at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:783)
at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:741)
at android.view.LayoutInflater.inflate(LayoutInflater.java:492)
at android.view.LayoutInflater.inflate(LayoutInflater.java:423)
at android.view.LayoutInflater.inflate(LayoutInflater.java:374)
at android.widget.Editor.showError(Editor.java:505)
at android.widget.Editor.onFocusChanged(Editor.java:1237)
at android.widget.TextView.onFocusChanged(TextView.java:9821)
at android.view.View.handleFocusGainInternal(View.java:6631)
at android.view.View.requestFocusNoSearch(View.java:10890)
at android.view.View.requestFocus(View.java:10869)
at android.view.View.requestFocus(View.java:10836)
at android.view.View.requestFocus(View.java:10778)
at com.example.zachmarcelo.softcash.RegisterActivity.registerUser(RegisterActivity.java:74)
at com.example.zachmarcelo.softcash.RegisterActivity.onClick(RegisterActivity.java:143)
at android.view.View.performClick(View.java:6291)
at android.view.View$PerformClick.run(View.java:24931)
at android.os.Handler.handleCallback(Handler.java:808)
at android.os.Handler.dispatchMessage(Handler.java:101)
at android.os.Looper.loop(Looper.java:166)
at android.app.ActivityThread.main(ActivityThread.java:7425)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.Zygote$MethodAndArgsCaller.run(Zygote.java:245)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:921)
and this is what is supposed to be happening: (works perfectly in name text but not in other edittexts)
screenshot of mobile app
any help will be appreciated :D

My guess is that it has something to do with what you put into #style/TextLabel.
When you have an error with password or email you request focus programmatically. Which is fine, however when that happens something in your style is looking for a color resource which doesn't exist. That's what's causing the error.

The error seems to be for getColor() method of textview, your primary color has some problem, please check that.

app keeps stopping when clicks on imagebutton [duplicate]

This question already has answers here:
What is a NullPointerException, and how do I fix it?
(12 answers)
Closed 5 years ago.
$ error in androidmonitor
02-02 14:22:48.870 3269-3269/com.example.applincatio.t E/AndroidRuntime: FATAL EXCEPTION: main
Process: com.example.applincatio.t, PID: 3269
java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.applincatio.t/com.example.applincatio.t.moddle}: java.lang.NullPointerException: Attempt to invoke virtual method 'void android.webkit.WebView.setWebChromeClient(android.webkit.WebChromeClient)' on a null object reference
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2646)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2707)
at android.app.ActivityThread.-wrap12(ActivityThread.java)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1460)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:154)
at android.app.ActivityThread.main(ActivityThread.java:6077)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:865)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:755)
Caused by: java.lang.NullPointerException: Attempt to invoke virtual method 'void android.webkit.WebView.setWebChromeClient(android.webkit.WebChromeClient)' on a null object reference
at com.example.applincatio.t.moddle.onCreate(moddle.java:20)
at android.app.Activity.performCreate(Activity.java:6664)
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1118)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2599)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2707) 
at android.app.ActivityThread.-wrap12(ActivityThread.java) 
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1460) 
at android.os.Handler.dispatchMessage(Handler.java:102) 
at android.os.Looper.loop(Looper.java:154) 
at android.app.ActivityThread.main(ActivityThread.java:6077) 
at java.lang.reflect.Method.invoke(Native Method) 
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:865) 
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:755) 
$main activity.java
package com.example.applincatio.t;
import android.content.Intent;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.ImageButton;
import android.widget.ImageView;
import static com.example.applincatio.t.R.*;
import static com.example.applincatio.t.R.id.moddle1;
public class MainActivity extends AppCompatActivity implements View.OnClickListener {
ImageView moddle;
ImageButton outlook;
ImageButton contactus;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(layout.activity_main);
moddle = (ImageView) findViewById(moddle1);
ImageView moddle = (ImageView) findViewById(moddle1);
moddle.setOnClickListener(this);
}
public void onClick(View view) {
switch (view.getId()) {
case moddle1:
Intent imprintIntent = new Intent(MainActivity.this, moddle.class);
imprintIntent.putExtra("webivew", moddle1);
this.startActivity(imprintIntent);
break;
case id.outlook:
Intent contactIntent = new Intent(MainActivity.this, moddle.class);
// contactIntent.putExtra("webivewContact", outlook);
this.startActivity(contactIntent);
break;
case id.contactus:
Intent aboutIntent = new Intent(MainActivity.this, moddle.class);
//aboutIntent.putExtra("webivewAbout", contactus);
this.startActivity(aboutIntent);
break;
}
}
}
$moddle.java
package com.example.applincatio.t;
import android.content.Intent;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.webkit.WebChromeClient;
import android.webkit.WebView;
public class moddle extends AppCompatActivity {
String url;
WebView webView;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
webView = (WebView) findViewById(R.id.web_link);
webView.clearCache(true);
webView.clearHistory();
webView.getSettings().setJavaScriptEnabled(true);
Intent intent = this.getIntent();
if (intent != null) {
Bundle data = getIntent().getExtras();
if (data.containsKey("webivew")) { //i have changed this param to match the intent passed
url = data.getString("webivew");
}
if (data.containsKey("webivewContact")) {
url = data.getString("webivewContact");
}
if (data.containsKey("webivewAbout")) {
url = data.getString("webivewAbout");
}
webView.setWebChromeClient(new WebChromeClient() {
public void onProgressChanged(WebView wView, int progress) {
// webViewActivity.setTitle("Loading...");
// webViewActivity.requestWindowFeature(progress * 100);
if(progress == 100) {
// webViewActivity.setTitle(R.string.app_name);
}
}
});
webView.loadUrl(url);
}
}
}
$activitymain.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:id="#+id/activity_main"
android:layout_width="match_parent"
android:background="#drawable/p"
android:layout_height="match_parent"
android:orientation="vertical"
android:paddingBottom="#dimen/activity_vertical_margin"
android:paddingLeft="#dimen/activity_horizontal_margin"
android:paddingRight="#dimen/activity_horizontal_margin"
android:paddingTop="#dimen/activity_vertical_margin"
tools:context="com.example.applincatio.t.MainActivity"
android:weightSum="1">
<GridLayout
android:layout_width="match_parent"
android:rowCount="4"
android:columnCount="2"
android:layout_height="530dp"
android:alignmentMode="alignMargins"
android:columnOrderPreserved="false"
android:id="#+id/gridview"
android:padding="14dp">
<LinearLayout
android:layout_gravity="center_horizontal|center_vertical"
android:layout_margin="16dp"
android:orientation="vertical"
android:layout_width="wrap_content"
android:layout_height="wrap_content">
<ImageView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center"
android:id="#+id/moddle1"
android:src="#drawable/moddle"/>
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="MODDLE"
android:textColor="#fff"
android:textStyle="bold"
android:textAppearance="#style/TextAppearance.AppCompat.Headline" />
</LinearLayout>
<LinearLayout
android:layout_gravity="center_horizontal|center_vertical"
android:layout_margin="16dp"
android:orientation="vertical"
android:layout_width="wrap_content"
android:layout_height="wrap_content">
<ImageButton
android:layout_width="96dp"
android:layout_height="139dp"
android:id="#+id/outlook"
android:layout_gravity="center"
android:src="#drawable/ou"/>
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="OUTLOOK"
android:gravity="bottom"
android:textAlignment="center"
android:textColor="#ffffff"
android:textStyle="bold"
android:textAppearance="#style/TextAppearance.AppCompat.Headline" />
</LinearLayout>
<LinearLayout
android:layout_gravity="center_horizontal|center_vertical"
android:layout_margin="16dp"
android:orientation="vertical"
android:layout_width="wrap_content"
android:layout_height="wrap_content">
<ImageButton
android:layout_width="122dp"
android:layout_height="141dp"
android:layout_gravity="center"
android:id="#+id/contactus"
android:src="#drawable/cont"/>
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="CONTACT US"
android:textSize="20dp"
android:textColor="#ffff"
android:textStyle="bold"
android:textAppearance="#style/TextAppearance.AppCompat.Headline" />
</LinearLayout>
<LinearLayout
android:layout_gravity="center_horizontal|center_vertical"
android:layout_margin="16dp"
android:orientation="vertical"
android:layout_width="wrap_content"
android:layout_height="wrap_content">
<ImageButton
android:layout_width="123dp"
android:layout_height="128dp"
android:onClick="onClick"
android:layout_gravity="center"
android:src="#drawable/vi"
android:id="#+id/visitus" />
<TextView
android:layout_width="wrap_content"
android:layout_height="48dp"
android:text="VISIT US"
android:gravity="bottom"
android:textAlignment="center"
android:textColor="#ffffff"
android:textStyle="bold"
android:textAppearance="#style/TextAppearance.AppCompat.Headline" />
</LinearLayout>
</GridLayout>
</LinearLayout>
when i run the app. it is running but when i click on any imagebutton the app keeps stopping. i cant understand the mistake i did .in image you can see my layout its running but imagebuttons are not working
please any one help me
thanks in advance

Try the below one,
package com.example.applincatio.t;
import android.content.Intent;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.webkit.WebChromeClient;
import android.webkit.WebView;
public class moddle extends AppCompatActivity {
String url;
WebView webView;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
webView = (WebView) findViewById(R.id.web_link);
webView.clearCache(true);
webView.clearHistory();
webView.getSettings().setJavaScriptEnabled(true);
Intent intent = this.getIntent();
if (intent != null) {
Bundle data = getIntent().getExtras();
if (data.containsKey("webview")) {
url = data.getString("webview");
}
if (data.containsKey("webivewContact")) {
url = data.getString("webivewContact");
}
if (data.containsKey("webivewAbout")) {
url = data.getString("webivewAbout");
}
webView.setWebChromeClient(new WebChromeClient() {
public void onProgressChanged(WebView wView, int progress) {
// webViewActivity.setTitle("Loading...");
// webViewActivity.requestWindowFeature(progress * 100);
if(progress == 100) {
// webViewActivity.setTitle(R.string.app_name);
}
}
});
url = "https://moodle.kluniversity.in/login/index.php";
webView.loadUrl(url);
}
}
}
Thanks!

Error with new intent ANDROID STUDIO [duplicate]

This question already has answers here:
What is a NullPointerException, and how do I fix it?
(12 answers)
Closed 5 years ago.
package com.example.alex.askii;
import android.content.Intent;
import android.support.v7.app.AppCompatActivity;
import android.graphics.Color;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.Toast;
import java.sql.DriverManager;
import java.sql.Connection;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
//Alex Levin
public class Login extends AppCompatActivity {
Button login;
Button signUp;
EditText userNameET;
EditText passWordET;
DatabaseHelper helper = new DatabaseHelper(this);
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_login);
login = (Button)findViewById(R.id.Login);
signUp = (Button)findViewById(R.id.signUp);
userNameET = (EditText)findViewById(R.id.username);
passWordET = (EditText)findViewById(R.id.password);
login.setOnClickListener(new View.OnClickListener(){
#Override
public void onClick(View v){
//get text valiues
String userName = userNameET.getText().toString();
String passWord = passWordET.getText().toString();
//Query in java the username
String actualPassword = helper.searchPass(userName);
//If Correct
if(passWord.equals(actualPassword)){
Toast.makeText(getApplicationContext(),
"Redirecting...", Toast.LENGTH_SHORT).show();
/*
Intent i = new Intent(mainActivity.this, display.class);
i.putExtra("UserName", str);
startActivity(i)
Example code to go to next activity ^^
*/
}else{
Toast.makeText(getApplicationContext(), "Invalid Username Or Password", Toast.LENGTH_SHORT).show();
}
}
});
signUp.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
Intent i = new Intent(Login.this, signUP.class);
startActivity(i);
}
});
}
}
<?xml version="1.0" encoding="utf-8"?>
<android.support.constraint.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context="com.example.alex.askii.Login">
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Askii Login"
android:textSize = "30dp"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintLeft_toLeftOf="parent"
app:layout_constraintRight_toRightOf="parent"
app:layout_constraintTop_toTopOf="parent"
app:layout_constraintVertical_bias="0.033"
tools:layout_constraintRight_creator="1"
tools:layout_constraintLeft_creator="1" />
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text= "Username:"
android:textSize="20dp"
app:layout_constraintRight_toLeftOf="#+id/username"
tools:layout_constraintRight_creator="1"
tools:layout_constraintBottom_creator="1"
app:layout_constraintBottom_toBottomOf="#+id/username"
android:layout_marginEnd="7dp"
android:layout_marginBottom="4dp"
android:layout_marginRight="7dp" />
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text= "Password:"
android:textSize="20dp"
android:id="#+id/textView"
tools:layout_constraintBottom_creator="1"
android:layout_marginStart="16dp"
app:layout_constraintBottom_toBottomOf="parent"
tools:layout_constraintLeft_creator="1"
android:layout_marginBottom="169dp"
app:layout_constraintLeft_toLeftOf="parent"
android:layout_marginLeft="16dp" />
<Button xmlns:android="http://schemas.android.com/apk/res/android"
android:id="#+id/Login"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Login"
android:onClick="login"
tools:layout_constraintRight_creator="1"
tools:layout_constraintBottom_creator="1"
app:layout_constraintBottom_toBottomOf="parent"
android:layout_marginEnd="84dp"
app:layout_constraintRight_toRightOf="parent"
android:layout_marginBottom="88dp"
android:layout_marginRight="130dp" />
<EditText
android:id="#+id/password"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:ems="10"
android:inputType="textPassword"
tools:layout_constraintRight_creator="1"
app:layout_constraintRight_toRightOf="#+id/username"
app:layout_constraintBaseline_toBaselineOf="#+id/textView"
tools:layout_constraintBaseline_creator="1"
tools:layout_constraintLeft_creator="1"
app:layout_constraintLeft_toLeftOf="#+id/username" />
<EditText
android:id="#+id/username"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:ems="10"
android:inputType="textPersonName"
android:text="Enter Username"
tools:layout_constraintBottom_creator="1"
app:layout_constraintBottom_toTopOf="#+id/password"
android:layout_marginStart="11dp"
tools:layout_constraintLeft_creator="1"
android:layout_marginBottom="20dp"
app:layout_constraintLeft_toRightOf="#+id/textView"
android:layout_marginLeft="11dp" />
<Button xmlns:android="http://schemas.android.com/apk/res/android"
android:id="#+id/signUp"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Sign Up"
tools:layout_constraintRight_creator="1"
tools:layout_constraintBottom_creator="1"
app:layout_constraintBottom_toBottomOf="parent"
android:layout_marginEnd="84dp"
app:layout_constraintRight_toRightOf="parent"
android:layout_marginRight="216dp"
android:layout_marginBottom="47dp" />
</android.support.constraint.ConstraintLayout>
package com.example.alex.askii;
import android.app.Activity;
import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.Toast;
/**
* Created by Alex on 12/30/2017.
*/
public class signUP extends AppCompatActivity{
#Override
protected void onCreate(Bundle savedInstanceState){
super.onCreate(savedInstanceState);
setContentView(R.layout.signup);
}
Button signUpOnPage = (Button)findViewById(R.id.signUpOnPage);
public void onSignUpOnPage(View v){
if(v.getId() == R.id.signUpOnPage){
EditText userName = (EditText)findViewById(R.id.newUserName);
EditText passWord = (EditText)findViewById(R.id.newPassWord);
EditText confPassword = (EditText)findViewById(R.id.newUserName);
String userNameString = userName.getText().toString();
String passWordString = passWord.getText().toString();
String confPasswordString = confPassword.getText().toString();
if(!passWordString.equals(confPasswordString)){
Toast check = Toast.makeText(signUP.this, "Passwords Don't Match", Toast.LENGTH_SHORT);
check.show();
}
}
}
}
For some reason I am getting the following error
12-30 02:39:59.308 1969-1969/com.example.alex.askii E/AndroidRuntime: FATAL EXCEPTION: main
java.lang.RuntimeException: Unable to instantiate activity ComponentInfo{com.example.alex.askii/com.example.alex.askii.signUP}: java.lang.NullPointerException
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1880)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:1981)
at android.app.ActivityThread.access$600(ActivityThread.java:123)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1147)
at android.os.Handler.dispatchMessage(Handler.java:99)
at android.os.Looper.loop(Looper.java:137)
at android.app.ActivityThread.main(ActivityThread.java:4424)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:511)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:784)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:551)
at dalvik.system.NativeStart.main(Native Method)
Caused by: java.lang.NullPointerException
at android.support.v7.app.AppCompatDelegateImplBase.<init>(AppCompatDelegateImplBase.java:118)
at android.support.v7.app.AppCompatDelegateImplV9.<init>(AppCompatDelegateImplV9.java:152)
at android.support.v7.app.AppCompatDelegateImplV11.<init>(AppCompatDelegateImplV11.java:29)
at android.support.v7.app.AppCompatDelegateImplV14.<init>(AppCompatDelegateImplV14.java:53)
at android.support.v7.app.AppCompatDelegate.create(AppCompatDelegate.java:204)
at android.support.v7.app.AppCompatDelegate.create(AppCompatDelegate.java:184)
at android.support.v7.app.AppCompatActivity.getDelegate(AppCompatActivity.java:518)
at android.support.v7.app.AppCompatActivity.findViewById(AppCompatActivity.java:189)
at com.example.alex.askii.signUP.<init>(signUP.java:16)
at java.lang.Class.newInstanceImpl(Native Method)
at java.lang.Class.newInstance(Class.java:1319)
at android.app.Instrumentation.newActivity(Instrumentation.java:1023)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1871)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:1981) 
at android.app.ActivityThread.access$600(ActivityThread.java:123) 
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1147) 
at android.os.Handler.dispatchMessage(Handler.java:99) 
at android.os.Looper.loop(Looper.java:137) 
at android.app.ActivityThread.main(ActivityThread.java:4424) 
at java.lang.reflect.Method.invokeNative(Native Method) 
at java.lang.reflect.Method.invoke(Method.java:511) 
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:784) 
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:551) 
at dalvik.system.NativeStart.main(Native Method) 
I am really unsure why this is happening maybe it is something wrong with my manifests but I doubt it because the manifest was autogenerated. Please help I can't find the answer online because it seems like I followed everything online correctly this is the last place I came to for help I am so frustrated right now!

Move
signUpOnPage = (Button)findViewById(R.id.signUpOnPage);
to onCreate()

Android Studio: java.lang.NullPointerException: Attempt to invoke virtual method on a null object reference [TextView]

I have searched for an answer that works for me but have not come across anything that helped.
My problem is that I am linking a TextView to another activity, however when clicked on throws a NullPointerException
This is the error:
01-18 07:03:41.882 14021-14035/com.j2fx.msc_driverlogin E/Surface: getSlotFromBufferLocked: unknown buffer: 0xab7d7650
01-18 07:03:42.729 14021-14021/com.j2fx.msc_driverlogin E/AndroidRuntime: FATAL EXCEPTION: main
01-18 07:03:42.729 14021-14021/com.j2fx.msc_driverlogin E/AndroidRuntime: Process: com.j2fx.msc_driverlogin, PID: 14021
01-18 07:03:42.729 14021-14021/com.j2fx.msc_driverlogin E/AndroidRuntime: java.lang.RuntimeException: Unable to start activity ComponentInfo{com.j2fx.msc_driverlogin/com.j2fx.msc_driverlogin.RegisterNew}: java.lang.NullPointerException: Attempt to invoke virtual method 'void android.widget.Button.setOnClickListener(android.view.View$OnClickListener)' on a null object reference
01-18 07:03:42.729 14021-14021/com.j2fx.msc_driverlogin E/AndroidRuntime: at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2416)
01-18 07:03:42.729 14021-14021/com.j2fx.msc_driverlogin E/AndroidRuntime: at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2476)
01-18 07:03:42.729 14021-14021/com.j2fx.msc_driverlogin E/AndroidRuntime: at android.app.ActivityThread.-wrap11(ActivityThread.java)
01-18 07:03:42.729 14021-14021/com.j2fx.msc_driverlogin E/AndroidRuntime: at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1344)
(quite a lot more stack trace but probably not relevant)
Here is the Login.class
package com.j2fx.msc_driverlogin;
import android.content.Intent;
import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;
public class Login extends AppCompatActivity implements View.OnClickListener {
Button bLogin;
EditText etUsername, etPassword;
TextView tvRegisterLink;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_login);
etUsername = (EditText) findViewById(R.id.etUsername);
etPassword = (EditText) findViewById(R.id.etPassword);
bLogin = (Button) findViewById(R.id.bLogin);
tvRegisterLink = (TextView) findViewById(R.id.tvRegisterLink);
bLogin.setOnClickListener(this);
tvRegisterLink.setOnClickListener(this);
}
#Override
public void onClick(View v) {
switch (v.getId()){
case R.id.bLogin:
// will add login code here
break;
case R.id.tvRegisterLink:
startActivity(new Intent(this, Register.class));
break;
}
}
}
Here is the Activity_Login.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:tools="http://schemas.android.com/tools"
xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:padding="10dp"
android:orientation="vertical"
android:layout_height="match_parent" >
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Driver ID"/>
<EditText
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginBottom="10dp"
android:id="#+id/etUsername"/>
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Password"/>
<EditText
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:inputType="numberPassword"
android:layout_marginBottom="10dp"
android:id="#+id/etPassword"/>
<Button
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="Login"
android:id="#+id/bLogin"/>
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center_horizontal"
android:textStyle="bold"
android:text="Register new account"
android:id="#+id/tvRegisterLink"/>
</LinearLayout>
Here is the Register.class
package com.j2fx.msc_driverlogin;
import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
public class Register extends AppCompatActivity implements View.OnClickListener {
Button bRegister;
EditText etName, etAddress, etDateOfBirth, etVehicleReg;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_register);
etName = (EditText) findViewById(R.id.etName);
etAddress = (EditText) findViewById(R.id.etAddress);
etDateOfBirth = (EditText) findViewById(R.id.etDateOfBirth);
etVehicleReg = (EditText) findViewById(R.id.etVehicleReg);
bRegister.setOnClickListener(this);
}
#Override
public void onClick(View v) {
switch (v.getId()){
case R.id.bRegister:
break;
}
}
}
And finaly the Activity_Register.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:tools="http://schemas.android.com/tools"
xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:padding="10dp"
android:orientation="vertical"
android:layout_height="match_parent" >
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Name"/>
<EditText
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginBottom="10dp"
android:id="#+id/etName"/>
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Address"/>
<EditText
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginBottom="10dp"
android:id="#+id/etAddress"/>
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Date of Birth"/>
<EditText
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:inputType="date"
android:layout_marginBottom="10dp"
android:id="#+id/etDateOfBirth"/>
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Vehicle Reg"/>
<EditText
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:inputType="text"
android:layout_marginBottom="10dp"
android:id="#+id/etVehicleReg"/>
<Button
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="Register"
android:id="#+id/bRegister"/>
</LinearLayout>
I have checked thoroughly and cannot see where I have gone wrong, although I am new to this so possibly missing something trivial.
Some points:
The id tvRegisterLink is within the same view
I have initialised tvRegisterLink before setOnClickListener
I have declared tvRegisterLink before the method onCreate
There is no duplication of the tvRegisterLink ID
Any ideas or pointers in the right direction would be great !
Thanks.

You are never assigning bRegister in the Register.onCreate method before setting the click listener on it.
bRegister = (Button) findViewById(R.id.bRegister);

You are not instantiating Button bRegister; in class Register, why it is giving error while receiving the click event.

Take a look at the error and the Register Class
ava.lang.NullPointerException: Attempt to invoke virtual method 'void android.widget.Button.setOnClickListener(android.view.View$OnClickListener)' on a null object referenc
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_register);
etName = (EditText) findViewById(R.id.etName);
etAddress = (EditText) findViewById(R.id.etAddress);
etDateOfBirth = (EditText) findViewById(R.id.etDateOfBirth);
etVehicleReg = (EditText) findViewById(R.id.etVehicleReg);
bRegister.setOnClickListener(this);
}
bRegister is not initialised.
just add
bRegister = (Button) findViewById(R.id.bRegister);