Here's the code -
public class login extends AppCompatActivity implements View.OnClickListener {
private Button signIn;
private ProgressDialog progressDialog;
private EditText emailID;
private EditText password1;
private TextView emailLabel;
private TextView passwordLabel;
private FirebaseAuth firebaseAuth;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_login);
firebaseAuth = FirebaseAuth.getInstance();
progressDialog = new ProgressDialog(this);
emailID = (EditText)findViewById(R.id.txtFieldEmailID);
password1 = (EditText) findViewById(R.id.txtFieldPassword);
emailLabel = (TextView) findViewById(R.id.labelEmail);
passwordLabel = (TextView) findViewById(R.id.labelPassword);
signIn.setOnClickListener(this);
}
private void loginUser(){
String email = emailID.getText().toString().trim();
String password = password1.getText().toString().trim();
if(TextUtils.isEmpty(email)){
//email field is empty
Toast.makeText(this,"Please enter email",Toast.LENGTH_LONG).show();
return;
}
if(TextUtils.isEmpty(password)){
//password is empty
Toast.makeText(this,"Please enter your password",Toast.LENGTH_LONG).show();
return;
}
//if validations are ok
//show a progressbar
firebaseAuth.signInWithEmailAndPassword(email, password)
.addOnCompleteListener(this, new OnCompleteListener<AuthResult>() {
public static final String TAG ="";
@Override
public void onComplete(@NonNull Task<AuthResult> task) {
if (task.isSuccessful()) {
// Sign in success, update UI with the signed-in user's information
Log.d(TAG, "signInWithEmail:success");
FirebaseUser user = firebaseAuth.getCurrentUser();
updateUI(user);
} else {
// If sign in fails, display a message to the user.
Log.w(TAG, "signInWithEmail:failure", task.getException());
Toast.makeText(login.this, "Authentication failed.",
Toast.LENGTH_SHORT).show();
updateUI(null);
}
// ...
}
private void updateUI(FirebaseUser user) {
progressDialog.setMessage("User has signed in");
progressDialog.show();
}
});
}
@Override
public void onClick(View view) {
if(view == signIn){
loginUser();
}
}
}
Error that I am getting on starting the application - 01-13 17:07:13.543 5027-5058/com.example.kinnari.trial2 D/FA: Logging event (FE): user_engagement(_e), Bundle[{firebase_event_origin(_o)=auto, engagement_time_msec(_et)=2716, firebase_screen_class(_sc)=MainActivity, firebase_screen_id(_si)=-7572526684473257642}] 01-13 17:07:13.734 5027-5027/com.example.kinnari.trial2 D/AndroidRuntime: Shutting down VM 01-13 17:07:13.737 5027-5027/com.example.kinnari.trial2 E/AndroidRuntime: FATAL EXCEPTION: main Process: com.example.kinnari.trial2, PID: 5027 java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.kinnari.trial2/com.example.kinnari.trial2.login}: java.lang.NullPointerException: Attempt to invoke virtual method 'void android.widget.Button.setOnClickListener(android.view.View$OnClickListener)' on a null object reference at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2778) at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2856) at android.app.ActivityThread.-wrap11(Unknown Source:0) at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1589) at android.os.Handler.dispatchMessage(Handler.java:106) at android.os.Looper.loop(Looper.java:164) at android.app.ActivityThread.main(ActivityThread.java:6494) at java.lang.reflect.Method.invoke(Native Method) at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:438) at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:807) Caused by: java.lang.NullPointerException: Attempt to invoke virtual method 'void android.widget.Button.setOnClickListener(android.view.View$OnClickListener)' on a null object reference at com.example.kinnari.trial2.login.onCreate(login.java:46) at android.app.Activity.performCreate(Activity.java:6999) at android.app.Activity.performCreate(Activity.java:6990) at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1214) at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2731) at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2856) at android.app.ActivityThread.-wrap11(Unknown Source:0) at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1589) at android.os.Handler.dispatchMessage(Handler.java:106) at android.os.Looper.loop(Looper.java:164) at android.app.ActivityThread.main(ActivityThread.java:6494) at java.lang.reflect.Method.invoke(Native Method) at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:438) at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:807) 01-13 17:07:13.851 5027-5047/com.example.kinnari.trial2 I/zygote: Background concurrent copying GC freed 6839(912KB) AllocSpace objects, 3(124KB) LOS objects, 50% free, 1707KB/3MB, paused 6.740ms total 111.655ms 01-13 17:24:04.987 5027-5054/com.example.kinnari.trial2 W/DynamiteModule: Local module descriptor class for com.google.firebase.auth not found.
