How to Create Multi User Login Apps in Android?

1.Open Android Studio, go to file>new>new project; give application name click next, select phone and tablets;click next, select empty activity click next and finally click finish.

Now you project will open in android studio. Go to res>layout>activity_main.xml. Double click on activity_mail.xml file, select design section. And drag and drop two edittext and one button and change their properties as shown in the video. OR simply copy following code; keep in mind that you need to change the package name and application name.

Designing code:

<?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=".MainActivity">

<TextView
android:id="@+id/textView7"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginBottom="55dp"
android:layout_marginEnd="8dp"
android:layout_marginRight="8dp"
android:layout_marginTop="16dp"
android:text="Username"
android:textSize="25dp"
app:layout_constraintBottom_toTopOf="@+id/textView8"
app:layout_constraintEnd_toStartOf="@+id/txtUser"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent" />

<TextView
android:id="@+id/textView8"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginBottom="60dp"
android:layout_marginEnd="11dp"
android:layout_marginRight="11dp"
android:text="Password"
android:textSize="25dp"
app:layout_constraintBottom_toTopOf="@+id/textView9"
app:layout_constraintEnd_toStartOf="@+id/txtPass"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="@+id/textView7" />

<TextView
android:id="@+id/textView9"
android:layout_width="0dp"
android:layout_height="0dp"
android:layout_marginBottom="285dp"
android:layout_marginEnd="36dp"
android:layout_marginLeft="16dp"
android:layout_marginRight="36dp"
android:layout_marginStart="16dp"
android:text="User Type"
android:textSize="20dp"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toStartOf="@+id/spinner"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="@+id/textView8" />

<EditText
android:id="@+id/txtUser"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginBottom="34dp"
android:layout_marginTop="16dp"
android:ems="10"
android:inputType="textPersonName"
android:text=""
app:layout_constraintBottom_toTopOf="@+id/txtPass"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toEndOf="@+id/textView7"
app:layout_constraintTop_toTopOf="parent" />

<EditText
android:id="@+id/txtPass"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginBottom="33dp"
android:ems="10"
android:inputType="textPersonName"
android:text=""
app:layout_constraintBottom_toTopOf="@+id/spinner"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toEndOf="@+id/textView8"
app:layout_constraintTop_toBottomOf="@+id/txtUser" />

<Spinner
android:id="@+id/spinner"
android:layout_width="0dp"
android:layout_height="0dp"
android:layout_marginBottom="26dp"
android:layout_marginEnd="16dp"
android:layout_marginRight="16dp"
app:layout_constraintBottom_toTopOf="@+id/btnLogin"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toEndOf="@+id/textView9"
app:layout_constraintTop_toBottomOf="@+id/txtPass" />

<Button
android:id="@+id/btnLogin"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginBottom="214dp"
android:layout_marginEnd="7dp"
android:layout_marginRight="7dp"
android:text="Login"
android:textSize="25dp"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintTop_toBottomOf="@+id/spinner" />
</android.support.constraint.ConstraintLayout>

2. Now goto java>yourpackagename.com.applicationname in my case java>com.techsupportnep.multiuser>MainActivity.java

a. Inside the class declare the following variable as:

EditText _txtUser, _txtPass;
Button _btnLogin;
Spinner _spinner;

b. Before writing below code you have to add two activity in your application. So for thsi:

Inside the onCreate method initialize each control as:

_txtPass=(EditText)findViewById(R.id.txtPass);
_txtUser=(EditText)findViewById(R.id.txtUser);
_btnLogin=(Button)findViewById(R.id.btnLogin);
_spinner=(Spinner)findViewById(R.id.spinner);
ArrayAdapter <CharSequence> adapter = ArrayAdapter.createFromResource(this, R.array.usertype, R.layout.support_simple_spinner_dropdown_item);
_spinner.setAdapter(adapter);
_btnLogin.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
String item = _spinner.getSelectedItem().toString();
if(_txtUser.getText().toString().equals("admin")&& _txtPass.getText().toString().equals("admin")&& item.equals("admin")){
Intent intent = new Intent(MainActivity.this, admin.class);
startActivity(intent);

}else if(_txtUser.getText().toString().equals("admin")&& _txtPass.getText().toString().equals("admin")&& item.equals("user")){
Intent intent = new Intent(MainActivity.this, user.class);
startActivity(intent);
}else {
Toast.makeText(getApplicationContext(), "Error", Toast.LENGTH_LONG).show();
}

}
});

Press shift+f10 or simply click in the play button below the menu of the android studio and then select your AVD either builtin AVD , or third party AVD or your phone device and then click proceed.