10. Login & Logout Features in Android Application

 

Login & Logout Features in Android Application

File Name: activity_main.xml

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout 
    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:layout_height="match_parent"
    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.abbu.login_logout.MainActivity">

    <EditText
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:inputType="textPassword"
        android:ems="10"
        android:layout_alignParentTop="true"
        android:layout_centerHorizontal="true"
        android:layout_marginTop="187dp"
        android:id="@+id/editTextPass"
        android:hint="password" />

    <EditText
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:inputType="textPersonName"
        android:ems="10"
        android:layout_alignBottom="@+id/editTextPass"
        android:layout_alignEnd="@+id/editTextPass"
        android:layout_marginBottom="80dp"
        android:id="@+id/editTextUser"
        android:hint="username" />

    <Button
        android:text="Login"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_below="@+id/editTextPass"
        android:layout_centerHorizontal="true"
        android:layout_marginTop="72dp"
        android:id="@+id/button" />
</RelativeLayout>

File Name: MainActivity.java

package com.example.abbu.login_logout;

import android.content.Intent;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.Toast;

import static android.R.attr.value;

public class MainActivity extends AppCompatActivity {

    EditText username, password;
    Button login;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        username = (EditText) findViewById(R.id.editTextUser);
        password = (EditText) findViewById(R.id.editTextPass);
        login = (Button) findViewById(R.id.button);

        login.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                if(username.getText().toString().equals("admin") &&
                        password.getText().toString().equals("admin")){
                    Intent i = new Intent(MainActivity.this.getApplicationContext(),
                            Logout.class);
                    i.putExtra("message", value);
                    startActivity(i);
                }
                else{
                    Toast.makeText(MainActivity.this, "Invalid Details",
                            Toast.LENGTH_SHORT).show();
                }
            }
        });
    }
}

File Name: logout.xml

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical" android:layout_width="match_parent"
    android:layout_height="match_parent">

    <Button
        android:text="Logout"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignParentTop="true"
        android:layout_centerHorizontal="true"
        android:layout_marginTop="125dp"
        android:id="@+id/buttonLogout" />
</RelativeLayout>

File Name: Logout.java

package com.example.abbu.login_logout;

import android.app.Activity;
import android.content.DialogInterface;
import android.content.Intent;
import android.content.SharedPreferences;
import android.os.Bundle;
import android.support.v7.app.AlertDialog;
import android.util.Log;
import android.view.View;
import android.widget.Button;

import static android.content.ContentValues.TAG;

/**
 * Created by Abbu on 4/15/2017.
 */

public class Logout extends MainActivity {

    Button Logout;



    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.logout);
        Logout = (Button) findViewById(R.id.buttonLogout);

        Intent in = getIntent();
        String string = in.getStringExtra("message");
        Logout.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                AlertDialog.Builder builder = new AlertDialog.Builder(Logout.this);
                builder.setTitle("Confirmation PopUp!").
                        setMessage("You sure, that you want to logout?");
                builder.setPositiveButton("Yes",
                        new DialogInterface.OnClickListener() {
                            public void onClick(DialogInterface dialog, int id) {
                                Intent i = new Intent(getApplicationContext(),
                                        MainActivity.class);
                                startActivity(i);
                            }
                        });
                builder.setNegativeButton("No",
                        new DialogInterface.OnClickListener() {
                            public void onClick(DialogInterface dialog, int id) {
                                dialog.cancel();
                            }
                        });
                AlertDialog alert11 = builder.create();
                alert11.show();
            }
        });
    }
}

Output:
activity_main.xml
After clicking on LOGIN Button, logout.xml will apear.
After_Successful_Login (logout.xml)
Now, when you click on LOGOUT Button, a confirmation popup (dialog box) will appear.




Logout_Confirmation
After clicking on YES in the confirmation popup, we'll come back to activity_main.xml


After_Logout

9. Login Application in Android

 

Login Application in Android

FileName: activity_main.xml

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout
    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:layout_height="match_parent"
    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.abbu.login_page.MainActivity">

    <EditText
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:inputType="textPassword"
        android:ems="10"
        android:layout_alignParentTop="true"
        android:layout_centerHorizontal="true"
        android:layout_marginTop="187dp"
        android:id="@+id/editTextPass"
        android:hint="password" />

    <EditText
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:inputType="textPersonName"
        android:ems="10"
        android:layout_alignBottom="@+id/editTextPass"
        android:layout_alignEnd="@+id/editTextPass"
        android:layout_marginBottom="80dp"
        android:id="@+id/editTextUser"
        android:hint="username" />

    <Button
        android:text="Login"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_below="@+id/editTextPass"
        android:layout_centerHorizontal="true"
        android:layout_marginTop="72dp"
        android:id="@+id/button" />
</RelativeLayout>

FileName: MainActivity.java

package com.example.abbu.login_page;

import android.content.Intent;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.Toast;

public class MainActivity extends AppCompatActivity {

    EditText username, password;
    Button login;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        username = (EditText) findViewById(R.id.editTextUser);
        password = (EditText) findViewById(R.id.editTextPass);
        login = (Button) findViewById(R.id.button);

        login.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                if(username.getText().toString().equals("admin") &&
                        password.getText().toString().equals("admin")){
                    Toast.makeText(MainActivity.this, "Welcome " +
                            username.getText().toString(),
                            Toast.LENGTH_SHORT).show();
                }
                else{
                    Toast.makeText(MainActivity.this, "Invalid Details",
                            Toast.LENGTH_SHORT).show();
                }
            }
        });
    }
}

Output:
activity_main.xml
After Successful Login
After unsuccessful Login

8. Three Buttons Vertically Aligned & Background Color Usage in Android

 

Three Buttons Vertically Aligned & Background Color Usage in Android

FileName: activity_main.xml

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout 
    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:layout_height="match_parent"
    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.abbu.button_color.MainActivity">

    <Button
        android:text="GAMBOGE"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_below="@+id/buttonPatina"
        android:layout_alignStart="@+id/buttonPatina"
        android:layout_marginTop="30dp"
        android:id="@+id/buttonGamboge" />

    <Button
        android:text="AMBER"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_below="@+id/buttonGamboge"
        android:layout_alignStart="@+id/buttonGamboge"
        android:layout_marginTop="30dp"
        android:id="@+id/buttonAmber" />

    <Button
        android:text="PATINA"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:id="@+id/buttonPatina"
        android:layout_alignParentTop="true"
        android:layout_centerHorizontal="true" />
</RelativeLayout>

FileName: MainActivity.java

package com.example.abbu.button_color;

import android.graphics.Color;
import android.support.v4.content.ContextCompat;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.RelativeLayout;


public class MainActivity extends AppCompatActivity {

    Button btn1,btn2,btn3;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        btn1 = (Button) findViewById(R.id.buttonPatina);
        btn2 = (Button) findViewById(R.id.buttonGamboge);
        btn3 = (Button) findViewById(R.id.buttonAmber);

        btn1.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                RelativeLayout rl = (RelativeLayout)findViewById(R.id.activity_main);
                    rl.setBackgroundColor(Color.parseColor("#407A52"));
            }
        });

        btn2.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                RelativeLayout rl = (RelativeLayout)findViewById(R.id.activity_main);
                rl.setBackgroundColor(Color.parseColor("#FFB61E"));
            }
        });

        btn3.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                RelativeLayout rl = (RelativeLayout)findViewById(R.id.activity_main);
                rl.setBackgroundColor(Color.parseColor("#CA6924"));
            }
        });
    }
}

Output:
Three Buttons Vertically Aligned & Background Color Usage in Android
After clicking on PATINA Button, the background color changes to:
PATINA (#407A52)
After clicking on GAMBOGE Button, the background color changes to:

GAMBOGE (#FFB61E)
After clicking on AMBER Button, the background color changes to:



AMBER (#CA6924)

7. Radio Button, ImageView and Toast Usage in Android

 

Radio Button, ImageView and Toast Usage in Android

File Name: activity_main.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:id="@+id/activity_main"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    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.abbu.radio_power.MainActivity">

    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Enquire Teacher-in-Charge"
        android:id="@+id/textView" />

    <RadioGroup
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:id="@+id/choices"
        android:layout_below="@+id/textView"
        android:layout_alignParentStart="true"
        android:layout_alignParentEnd="true">

    <RadioButton
        android:text="Computer Science"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignParentStart="true"
        android:layout_marginStart="5dp"
        android:layout_marginTop="10dp"
        android:id="@+id/radioButtonCS" />

    <RadioButton
        android:text="Commerce"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignTop="@+id/radioButtonCS"
        android:layout_toEndOf="@+id/textView"
        android:layout_alignParentStart="false"
        android:layout_marginStart="5dp"
        android:layout_marginTop="10dp"
        android:id="@+id/radioButtonCO" />

    <RadioButton
        android:text="Chemistry"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignTop="@+id/radioButtonEL"
        android:layout_alignStart="@+id/radioButtonCO"
        android:layout_alignParentStart="false"
        android:layout_marginStart="5dp"
        android:layout_marginTop="10dp"
        android:id="@+id/radioButtonCH" />

    <RadioButton
        android:text="Electronics"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:id="@+id/radioButtonEL"
        android:layout_alignParentStart="false"
        android:layout_marginStart="5dp"
        android:layout_marginTop="10dp"
        android:layout_below="@+id/radioButtonCS"
        android:layout_alignStart="@+id/radioButtonCS" />
    

    </RadioGroup>

    <ImageView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        app:srcCompat="@mipmap/ic_launcher"
        android:id="@+id/imageView"
        android:layout_marginTop="41dp"
        android:layout_below="@+id/choices"
        android:layout_centerHorizontal="true" />
</RelativeLayout>

File Name: MainActivity.java

package com.example.abbu.radio_power;

import android.content.res.TypedArray;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.widget.AdapterView;
import android.widget.ImageView;
import android.widget.RadioButton;
import android.widget.RadioGroup;
import android.widget.Toast;

public class MainActivity extends AppCompatActivity {

    private TypedArray images;
    private ImageView itemImage;
    RadioButton rch = null;
    RadioButton rco = null;
    RadioButton rcs = null;
    RadioButton rel = null;
    RadioGroup rg = null;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        images = getResources().obtainTypedArray(R.array.radiobtn_image);
        itemImage = (ImageView) findViewById(R.id.imageView);
        rch = (RadioButton) findViewById(R.id.radioButtonCH);
        rco = (RadioButton) findViewById(R.id.radioButtonCO);
        rcs = (RadioButton) findViewById(R.id.radioButtonCS);
        rel = (RadioButton) findViewById(R.id.radioButtonEL);
        rg = (RadioGroup) findViewById(R.id.choices);

        rg.setOnCheckedChangeListener(new RadioGroup.OnCheckedChangeListener() {
            @Override
            public void onCheckedChanged(RadioGroup group, int checkedId) {
                if(checkedId == rch.getId()) {
                    itemImage.setImageResource(R.drawable.pic2);
                    Toast.makeText(MainActivity.this, "Dr. Neelu Dhir",
                            Toast.LENGTH_SHORT).show();
                }else if (checkedId == rco.getId()) {
                    itemImage.setImageResource(R.drawable.pic4);
                    Toast.makeText(MainActivity.this, "Ms. Sangeeta Relan",
                            Toast.LENGTH_SHORT).show();
                } else if (checkedId == rcs.getId()) {
                    itemImage.setImageResource(R.drawable.pic1);
                    Toast.makeText(MainActivity.this, "Dr. Vibha Gaur",
                            Toast.LENGTH_SHORT).show();
                } else {
                    itemImage.setImageResource(R.drawable.pic3);
                    Toast.makeText(MainActivity.this, "Dr. Ravneet Kaur",
                            Toast.LENGTH_SHORT).show();
                }
            }
        });
}
}

File Name: strings.xml

<resources>
    <string name="app_name">Radio_Power</string>

    <string-array name="radiobtn_image">
        <item>@drawable/pic1</item>
        <item>@drawable/pic2</item>
        <item>@drawable/pic3</item>
        <item>@drawable/pic4</item>
    </string-array>
</resources>

Output:
Radio Button, ImageView and Toast Usage in Android
Radio Button, ImageView and Toast Usage in Android

6. Spinner & Toast Usage in Android

 

Spinner & Toast Usage in Android

FileName: MainActivity.java

package com.example.abbu.spinner_select;

import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.AdapterView;
import android.widget.Spinner;
import android.widget.Toast;

public class MainActivity extends AppCompatActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        Spinner s = (Spinner) findViewById(R.id.spinner1);

        s.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener(){
            @Override
            public void onItemSelected(AdapterView<?> parent, View view, int position, long id)
            {
                Toast.makeText(MainActivity.this, parent.getSelectedItem().toString(),
                        Toast.LENGTH_SHORT).show();

            }

            @Override
            public void onNothingSelected(AdapterView<?> parent) {

            }
        });
    }
}

FileName: activity_main.xml

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout 
    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:layout_height="match_parent"
    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.abbu.spinner_select.MainActivity">

    <TextView
        android:text="Select one Country : "
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:layout_marginBottom="20dp"
        />

    <Spinner
        android:id="@+id/spinner1"
        android:entries="@array/country_names"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignParentTop="true"
        android:layout_centerHorizontal="true"
        android:layout_marginTop="30dp" />
</RelativeLayout>

FileName: strings.xml

<resources>
    <string name="app_name">Spinner_Select</string>

    <string-array name="country_names">
        <item>India</item>
        <item>Pakistan</item>
        <item>China</item>
        <item>Nepal</item>
        <item>Bangladesh</item>
        <item>Bhutan</item>
    </string-array>
</resources>


Output:

By default, India is the selected spinner item and toast named India will appear.
Spinner & Toast Usage in Android 
Now, we'll select any one country:


Spinner & Toast Usage in Android 
Finally, I selected Bhutan and a toast named Bhutan will appear.


Spinner & Toast Usage in Android 

5. Spinner in Android Application

 

Spinner in Android Application

File Name: MainActivity.java

package com.example.abbu.spinner_image;

import android.content.res.TypedArray;
import android.graphics.Color;
import android.support.v7.app.ActionBarActivity;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.widget.AdapterView;
import android.widget.ArrayAdapter;
import android.widget.ImageView;
import android.widget.Spinner;
import android.widget.TextView;
import android.widget.Toast;

import org.w3c.dom.Text;

public class MainActivity extends ActionBarActivity {

    private String[] Objects;

    private TypedArray images;

    private ImageView itemImage;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        // Casting
        Objects = getResources().getStringArray(R.array.object_array);
        images = getResources().obtainTypedArray(R.array.object_image);
        TextView spinnerHeader = (TextView)findViewById(R.id.textView);
        itemImage = (ImageView)findViewById(R.id.imageView);
        final Spinner spinner = (Spinner)findViewById(R.id.spinner);

        ArrayAdapter<String> spinnerAdapter = new ArrayAdapter<String>(
                getApplicationContext(),android.R.layout.simple_spinner_item, Objects);

        spinnerAdapter.setDropDownViewResource(
                android.R.layout.simple_spinner_dropdown_item);

        spinner.setAdapter(spinnerAdapter);

        spinner.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {
            @Override
           public void onItemSelected(AdapterView<?> parent, View view, int position, long id)
           {
                itemImage.setImageResource(images.getResourceId(
                        spinner.getSelectedItemPosition(), -1));
           }

            @Override
            public void onNothingSelected(AdapterView<?> parent) {
            }
        });
    }


}

File Name: activity_main.xml

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout 
    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:layout_height="match_parent"
    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.abbu.spinner_image.MainActivity">


    <TextView android:text="@string/option_select"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignParentTop="true"
        android:layout_alignParentLeft="true"
        android:layout_alignParentStart="true"
        android:layout_marginLeft="20dp"
        android:layout_marginStart="55dp"
        android:textSize="16sp"
        android:textStyle="bold"
        android:layout_marginTop="27dp"
        android:id="@+id/textView" />

    <Spinner
        android:id="@+id/spinner"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_marginRight="20dp"
        android:layout_below="@+id/textView"
        android:layout_alignLeft="@+id/textView"/>

    <ImageView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:id="@+id/imageView"
        android:layout_below="@+id/spinner"
        android:layout_alignLeft="@+id/spinner"
        android:layout_alignStart="@+id/spinner"
        android:layout_marginTop="55dp" />
</RelativeLayout>

File Name: strings.xml

<resources>
    <string name="app_name">Spinner_Image</string>

    <string name="option_select">Choose any one:</string>

    <string-array name="object_array">
        <item>Shah Rukh Khan</item>
        <item>Hrithik Roshan</item>
        <item>Leonardo DiCaprio</item>
        <item>Bryan Cranston</item>
    </string-array>

    <integer-array name="object_image">
        <item>@drawable/pic1</item>
        <item>@drawable/pic2</item>
        <item>@drawable/pic3</item>
        <item>@drawable/pic4</item>
    </integer-array>
</resources>

Output:


By default, the first item in the spinner is selected.

Spinner in Android Application

Now, choosing another item.


Spinner in Android Application

Finally, when clicked on Leonardo DiCaprio.


Spinner in Android Application