Untitled

//app fo setting an alarm

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

    <TimePicker
        android:id="@+id/timePicker"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_gravity="center" />

    <ToggleButton
        android:id="@+id/toggleButton"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_gravity="center"
        android:layout_margin="20dp"
        android:checked="false"
        android:onClick="OnToggleClicked" />

</LinearLayout>

Mainactivity.java

package com.example.akshay.alarm;

import android.app.AlarmManager;
import android.app.PendingIntent;
import android.content.Intent;
import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.view.View;
import android.widget.TimePicker;
import android.widget.Toast;
import android.widget.ToggleButton;

import java.util.Calendar;

public class MainActivity extends AppCompatActivity
{
    TimePicker alarmTimePicker;
    PendingIntent pendingIntent;
    AlarmManager alarmManager;

    @Override
    protected void onCreate(Bundle savedInstanceState)
    {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        alarmTimePicker = (TimePicker) findViewById(R.id.timePicker);
        alarmManager = (AlarmManager) getSystemService(ALARM_SERVICE);
    }
    public void OnToggleClicked(View view)
    {
        long time;
        if (((ToggleButton) view).isChecked())
        {
            Toast.makeText(MainActivity.this, "ALARM ON", Toast.LENGTH_SHORT).show();
            Calendar calendar = Calendar.getInstance();
            calendar.set(Calendar.HOUR_OF_DAY, alarmTimePicker.getCurrentHour());
            calendar.set(Calendar.MINUTE, alarmTimePicker.getCurrentMinute());
            Intent intent = new Intent(this, AlarmReceiver.class);
            pendingIntent = PendingIntent.getBroadcast(this, 0, intent, 0);

            time=(calendar.getTimeInMillis()-(calendar.getTimeInMillis()%60000));
            if(System.currentTimeMillis()>time)
            {
                if (calendar.AM_PM == 0)
                    time = time + (1000*60*60*12);
                else
                    time = time + (1000*60*60*24);
            }
            alarmManager.setRepeating(AlarmManager.RTC_WAKEUP, time, 10000, pendingIntent);
        }
        else
        {
            alarmManager.cancel(pendingIntent);
            Toast.makeText(MainActivity.this, "ALARM OFF", Toast.LENGTH_SHORT).show();
        }
    }
}

AlarmReciver.java
package com.example.akshay.alarm;

import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.media.Ringtone;
import android.media.RingtoneManager;
import android.net.Uri;
import android.widget.Toast;

public class AlarmReceiver extends BroadcastReceiver
{
    @Override
    public void onReceive(Context context, Intent intent)
    {
        Toast.makeText(context, "Alarm! Wake up! Wake up!", Toast.LENGTH_LONG).show();
        Uri alarmUri = RingtoneManager.getDefaultUri(RingtoneManager.TYPE_ALARM);
        if (alarmUri == null)
        {
            alarmUri = RingtoneManager.getDefaultUri(RingtoneManager.TYPE_NOTIFICATION);
        }
        Ringtone ringtone = RingtoneManager.getRingtone(context, alarmUri);
        ringtone.play();
    }
}


////alert on recive a message
activity.main.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:layout_margin="10dp"
    android:orientation="vertical">

    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Message"
        android:textSize="30sp" />

    <EditText
        android:id="@+id/editText"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:singleLine="true"
        android:textSize="30sp" />

    <Button
        android:id="@+id/button"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_margin="30dp"
        android:layout_gravity="center"
        android:text="Notify"
        android:textSize="30sp"/>

</LinearLayout>


Mainactivity.java
package com.example.akshay.alarm;

import android.app.Notification;
import android.app.NotificationManager;
import android.app.PendingIntent;
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;

public class MainActivity extends AppCompatActivity
{
    Button notify;
    EditText e;
    @Override
    protected void onCreate(Bundle savedInstanceState)
    {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        notify= (Button) findViewById(R.id.button);
        e= (EditText) findViewById(R.id.editText);

        notify.setOnClickListener(new View.OnClickListener()
        {
            @Override
            public void onClick(View v)
            {
                Intent intent = new Intent(MainActivity.this, SecondActivity.class);
                PendingIntent pending = PendingIntent.getActivity(MainActivity.this, 0, intent, 0);
                Notification noti = new Notification.Builder(MainActivity.this).setContentTitle("New Message").setContentText(e.getText().toString()).setSmallIcon(R.mipmap.ic_launcher).setContentIntent(pending).build();
                NotificationManager manager = (NotificationManager) getSystemService(NOTIFICATION_SERVICE);
                noti.flags |= Notification.FLAG_AUTO_CANCEL;
                manager.notify(0, noti);
            }
        });
    }
}

Then Go to file
new>activity>emptyactivity
 name it as second activity


//read and write data to sdcard
Add the below line to android_mainfest.xml above the application tag
    <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"></uses-permission>

activity_main.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:layout_margin="20dp"
    android:orientation="vertical">

    <EditText
        android:id="@+id/editText"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:singleLine="true"
        android:textSize="30dp" />

    <Button
        android:id="@+id/button"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_margin="10dp"
        android:text="Write Data"
        android:textSize="30dp" />

    <Button
        android:id="@+id/button2"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_margin="10dp"
        android:text="Read data"
        android:textSize="30dp" />

    <Button
        android:id="@+id/button3"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_margin="10dp"
        android:text="Clear"
        android:textSize="30dp" />

</LinearLayout>

Mainactivity.java
package com.example.akshay.alarm;
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;

import java.io.BufferedReader;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.InputStreamReader;

public class MainActivity extends AppCompatActivity
{
    EditText e1;
    Button write,read,clear;
    @Override
    protected void onCreate(Bundle savedInstanceState)
    {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        e1= (EditText) findViewById(R.id.editText);
        write= (Button) findViewById(R.id.button);
        read= (Button) findViewById(R.id.button2);
        clear= (Button) findViewById(R.id.button3);

        write.setOnClickListener(new View.OnClickListener()
        {
            @Override
            public void onClick(View v)
            {
                String message=e1.getText().toString();
                try
                {
                    File f=new File("/sdcard/myfile.txt");
                    f.createNewFile();
                    FileOutputStream fout=new FileOutputStream(f);
                    fout.write(message.getBytes());
                    fout.close();
                    Toast.makeText(getBaseContext(),"Data Written in SDCARD",Toast.LENGTH_LONG).show();
                }
                catch (Exception e)
                {
                    Toast.makeText(getBaseContext(),e.getMessage(),Toast.LENGTH_LONG).show();
                }
            }
        });

        read.setOnClickListener(new View.OnClickListener()
        {
            @Override
            public void onClick(View v)
            {
                String message;
                String buf = "";
                try
                {
                    File f = new File("/sdcard/myfile.txt");
                    FileInputStream fin = new FileInputStream(f);
                    BufferedReader br = new BufferedReader(new InputStreamReader(fin));
                    while ((message = br.readLine()) != null)
                    {
                        buf += message;
                    }
                    e1.setText(buf);
                    br.close();
                    fin.close();
                    Toast.makeText(getBaseContext(),"Data Recived from SDCARD",Toast.LENGTH_LONG).show();
                }
                catch (Exception e)
                {
                    Toast.makeText(getBaseContext(), e.getMessage(), Toast.LENGTH_LONG).show();
                }
            }
        });

        clear.setOnClickListener(new View.OnClickListener()
        {
            @Override
            public void onClick(View v)
            {
                e1.setText("");
            }
        });
    }
}


////tic-toc-toe game
activity_main.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout 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"
    android:orientation="vertical"
    tools:context="com.codinginflow.tictactoe.MainActivity">

    <RelativeLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content">

        <TextView
            android:id="@+id/text_view_p1"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:freezesText="true"
            android:text="Player 1: 0"
            android:textSize="30sp" />

        <TextView
            android:id="@+id/text_view_p2"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_below="@+id/text_view_p1"
            android:freezesText="true"
            android:text="Player 2: 0"
            android:textSize="30sp" />

        <Button
            android:id="@+id/button_reset"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_alignParentEnd="true"
            android:layout_centerVertical="true"
            android:layout_marginEnd="33dp"
            android:text="reset" />

    </RelativeLayout>

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="0dp"
        android:layout_weight="1">

        <Button
            android:id="@+id/button_00"
            android:layout_width="0dp"
            android:layout_height="match_parent"
            android:layout_weight="1"
            android:freezesText="true"
            android:textSize="60sp" />

        <Button
            android:id="@+id/button_01"
            android:layout_width="0dp"
            android:layout_height="match_parent"
            android:layout_weight="1"
            android:freezesText="true"
            android:textSize="60sp" />

        <Button
            android:id="@+id/button_02"
            android:layout_width="0dp"
            android:layout_height="match_parent"
            android:layout_weight="1"
            android:freezesText="true"
            android:textSize="60sp" />

    </LinearLayout>

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="0dp"
        android:layout_weight="1">

        <Button
            android:id="@+id/button_10"
            android:layout_width="0dp"
            android:layout_height="match_parent"
            android:layout_weight="1"
            android:freezesText="true"
            android:textSize="60sp" />

        <Button
            android:id="@+id/button_11"
            android:layout_width="0dp"
            android:layout_height="match_parent"
            android:layout_weight="1"
            android:freezesText="true"
            android:textSize="60sp" />

        <Button
            android:id="@+id/button_12"
            android:layout_width="0dp"
            android:layout_height="match_parent"
            android:layout_weight="1"
            android:freezesText="true"
            android:textSize="60sp" />

    </LinearLayout>

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="0dp"
        android:layout_weight="1">

        <Button
            android:id="@+id/button_20"
            android:layout_width="0dp"
            android:layout_height="match_parent"
            android:layout_weight="1"
            android:freezesText="true"
            android:textSize="60sp" />

        <Button
            android:id="@+id/button_21"
            android:layout_width="0dp"
            android:layout_height="match_parent"
            android:layout_weight="1"
            android:freezesText="true"
            android:textSize="60sp" />

        <Button
            android:id="@+id/button_22"
            android:layout_width="0dp"
            android:layout_height="match_parent"
            android:layout_weight="1"
            android:freezesText="true"
            android:textSize="60sp" />

    </LinearLayout>

</LinearLayout>


mainActivity.java
package com.example.akshay.alarm;

import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.TextView;
import android.widget.Toast;

public class MainActivity extends AppCompatActivity implements View.OnClickListener {

    private Button[][] buttons = new Button[3][3];

    private boolean player1Turn = true;

    private int roundCount;

    private int player1Points;
    private int player2Points;

    private TextView textViewPlayer1;
    private TextView textViewPlayer2;

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

        textViewPlayer1 = findViewById(R.id.text_view_p1);
        textViewPlayer2 = findViewById(R.id.text_view_p2);

        for (int i = 0; i < 3; i++) {
            for (int j = 0; j < 3; j++) {
                String buttonID = "button_" + i + j;
                int resID = getResources().getIdentifier(buttonID, "id", getPackageName());
                buttons[i][j] = findViewById(resID);
                buttons[i][j].setOnClickListener(this);
            }
        }

        Button buttonReset = findViewById(R.id.button_reset);
        buttonReset.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                resetGame();
            }
        });
    }

    @Override
    public void onClick(View v) {
        if (!((Button) v).getText().toString().equals("")) {
            return;
        }

        if (player1Turn) {
            ((Button) v).setText("X");
        } else {
            ((Button) v).setText("O");
        }

        roundCount++;

        if (checkForWin()) {
            if (player1Turn) {
                player1Wins();
            } else {
                player2Wins();
            }
        } else if (roundCount == 9) {
            draw();
        } else {
            player1Turn = !player1Turn;
        }

    }

    private boolean checkForWin() {
        String[][] field = new String[3][3];

        for (int i = 0; i < 3; i++) {
            for (int j = 0; j < 3; j++) {
                field[i][j] = buttons[i][j].getText().toString();
            }
        }

        for (int i = 0; i < 3; i++) {
            if (field[i][0].equals(field[i][1])
                    && field[i][0].equals(field[i][2])
                    && !field[i][0].equals("")) {
                return true;
            }
        }

        for (int i = 0; i < 3; i++) {
            if (field[0][i].equals(field[1][i])
                    && field[0][i].equals(field[2][i])
                    && !field[0][i].equals("")) {
                return true;
            }
        }

        if (field[0][0].equals(field[1][1])
                && field[0][0].equals(field[2][2])
                && !field[0][0].equals("")) {
            return true;
        }

        if (field[0][2].equals(field[1][1])
                && field[0][2].equals(field[2][0])
                && !field[0][2].equals("")) {
            return true;
        }

        return false;
    }

    private void player1Wins() {
        player1Points++;
        Toast.makeText(this, "Player 1 wins!", Toast.LENGTH_SHORT).show();
        updatePointsText();
        resetBoard();
    }

    private void player2Wins() {
        player2Points++;
        Toast.makeText(this, "Player 2 wins!", Toast.LENGTH_SHORT).show();
        updatePointsText();
        resetBoard();
    }

    private void draw() {
        Toast.makeText(this, "Draw!", Toast.LENGTH_SHORT).show();
        resetBoard();
    }

    private void updatePointsText() {
        textViewPlayer1.setText("Player 1: " + player1Points);
        textViewPlayer2.setText("Player 2: " + player2Points);
    }

    private void resetBoard() {
        for (int i = 0; i < 3; i++) {
            for (int j = 0; j < 3; j++) {
                buttons[i][j].setText("");
            }
        }

        roundCount = 0;
        player1Turn = true;
    }

    private void resetGame() {
        player1Points = 0;
        player2Points = 0;
        updatePointsText();
        resetBoard();
    }

    @Override
    protected void onSaveInstanceState(Bundle outState) {
        super.onSaveInstanceState(outState);

        outState.putInt("roundCount", roundCount);
        outState.putInt("player1Points", player1Points);
        outState.putInt("player2Points", player2Points);
        outState.putBoolean("player1Turn", player1Turn);
    }

    @Override
    protected void onRestoreInstanceState(Bundle savedInstanceState) {
        super.onRestoreInstanceState(savedInstanceState);

        roundCount = savedInstanceState.getInt("roundCount");
        player1Points = savedInstanceState.getInt("player1Points");
        player2Points = savedInstanceState.getInt("player2Points");
        player1Turn = savedInstanceState.getBoolean("player1Turn");
    }
}


Cdma
import java.util.*;
public class Main{
	private int[][] walshTable;
	private int[][] copy;
	private int[] channelSeq;

	public void setUp(int data[],int numStations){
		walshTable=new int[numStations][numStations];
		copy=new int[numStations][numStations];

		buildWalshTable(numStations, 0, numStations-1, 0, numStations-1, false);
		showWalshTable(numStations);

		for(int i=0;i<numStations;i++)
			for(int j=0;j<numStations;j++){
				copy[i][j]=walshTable[i][j];
				walshTable[i][j]*=data[i];
			}
		channelSeq=new int [numStations];
		for (int i=0;i<numStations;i++)
			for(int j=0;j<numStations;j++){
				channelSeq[i]+=walshTable[j][i];
			}

	}

	public void buildWalshTable(int len,int i1,int i2,int j1,int j2,boolean val){
		if(len==2){
			if(!val){
				walshTable[i1][j1]=1;
				walshTable[i1][j2]=1;
				walshTable[i2][j1]=1;
				walshTable[i2][j2]=-1;
			}
			else{
				walshTable[i1][j1]=-1;
				walshTable[i1][j2]=-1;
				walshTable[i2][j1]=-1;
				walshTable[i2][j2]=1;
			}

		}
		else{
			int midi=(i1+i2)/2;
			int midj=(j1+j2)/2;

			buildWalshTable(len/2,i1,midi,j1,midj,val);
			buildWalshTable(len/2,midi+1,i2,j1,midj,val);
			buildWalshTable(len/2,i1,midi,midj+1,j2,val);
			buildWalshTable(len/2,midi+1,i2,midj+1,j2,!val);
		}

	}
	public void showWalshTable(int numStations){
		System.out.println("Walsh Table");
		for(int i=0;i<numStations;i++)
		{
			for(int j=0;j<numStations;j++){
				System.out.print(walshTable[i][j]+"\t");
			}
			System.out.println();
		}

	}
	public void listenTo(int numStations,int sourceStation){
		int innerProduct=0;
	for (int i=0;i< numStations;i++)
		innerProduct+=copy[sourceStation][i]*channelSeq[i];
	System.out.println("Data received is : "+innerProduct/numStations);

	}

	public static void main(String args[]){
		Main channel= new Main();
		int numStations=4;

		int[] data=new int[numStations];
		data[0]=-1;
		data[1]=-1;
		data[2]=0;
		data[3]=1;
		channel.setUp(data,numStations);
		int sourceStation=3;
		channel.listenTo(numStations,sourceStation);

	}
}


cdma python
def mult(c,d):
 return list(map(lambda x : x * d, c))

c1=[1,1,1,1]
c2=[1,-1,1,-1]
c3=[1,1,-1,-1]
c4=[1,-1,-1,1]
C=[c1,c2,c3,c4]

d=[int(x) for x in input("Enter data bits for 4 channels:").split()]
result=[]
for i in range(4):
 result.append(mult(C[i],d[i]))

print(result)
channel=[]
for i in range(4):
 res=0
 for j in range(4):
   res+=result[j][i]
 channel.append(res)

station=int(input("Enter station you want to listen:"))

res2=0
for i in range(4):
 res2+=channel[i]*C[station-1][i]

print("Data bit transmitted:",res2//4)


Phonebook
ANDROID : PHONEBOOK ActivityMain.xml:
 <?  xml version="1.0" encoding="utf-8"?>
 <LinearLayout 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"
    android:orientation="vertical"
    tools:context=".MainActivity" >

    <EditText
        android:id="@+id/etName"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:ems="10"
        android:inputType="textPersonName"
        android:hint="Name" />

    <EditText
        android:id="@+id/etPhone"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:ems="10"
        android:inputType="phone"
        android:hint="Phone Number"/>

    <EditText
        android:id="@+id/etEmail"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:ems="10"
        android:inputType="textEmailAddress"
        android:hint="Email"/>

    <EditText
        android:id="@+id/etAddress"
        android:layout_width="match_parent"
       android:layout_height="wrap_content"
        android:ems="10"
        android:inputType="textPostalAddress"
        android:hint="Address"/>

    <Button
        android:id="@+id/btnAdd"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="Add" />
    <Button
        android:id="@+id/btnView"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="View Contacts" />
 </LinearLayout>


ActivityView.xml:
 <?  xml version="1.0" encoding="utf-8"?>
 <LinearLayout 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=".ViewActivity"
    android:orientation="vertical">

    <TextView
        android:id="@+id/tvData"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text=""
        android:scrollbars="vertical"/>

 </LinearLayout>

 MainActivity.java:
 package com.example.phonebookmcc;
 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.widget.Toast.makeText  ;
 public class MainActivity extends AppCompatActivity {
    static DatabaseHandler dbH  ;
    EditText etName,etPhone,etAddress,etEmail;
   Button btnAdd,btnView;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main  );
        etAddress=(EditText)findViewById(R.id.etAddress  );
        etEmail=(EditText)findViewById(R.id.etEmail  );
        etName=(EditText)findViewById(R.id.etName  );
        etPhone=(EditText)findViewById(R.id.etPhone  );
        btnAdd=(Button)findViewById(R.id.btnAdd  );
        btnView=(Button)findViewById(R.id.btnView  );
        dbH  =new DatabaseHandler(this);
        btnAdd.setOnClickListener(new View.OnClickListener() {
            @Override            public void onClick(View v) {
                String name=etName.getText().toString();
                String phone=etPhone.getText().toString();
                String email=etEmail.getText().toString();
                String address=etAddress.getText().toString();
                int check=dbH  .addContact(name,phone,email,address);
                if (check==1){
                    Toast.makeText  (MainActivity.this,"CONTACT ADDED",Toast.LENGTH_SHORT  ).show();                    etAddress.setText("");
                    etPhone.setText("");
                    etEmail.setText("");
                    etName.setText("");
                    etName.requestFocus();
                }
                else {

 Toast.makeText  (MainActivity.this,"Issues",Toast.LENGTH_SHORT  ).show();
                }
            }
        });

        btnView.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                Intent i=new Intent(MainActivity.this,ViewActivity.class);
                startActivity(i);

            }
       });
    } }


ViewActivity.java:

 package com.example.phonebookmcc;

 import android.support.v7.app.AppCompatActivity;
 import android.os.Bundle;
 import android.text.method.ScrollingMovementMethod;
 import android.widget.TextView;

 public class ViewActivity extends AppCompatActivity {
 TextView tvData;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_view  );
        tvData=(TextView)findViewById(R.id.tvData  );
        String data=MainActivity.dbH  .viewContact();
        tvData.setMovementMethod(new ScrollingMovementMethod());
        if(data.length()==0)
            tvData.setText("No records to show");
        else
            tvData.setText(data);
    } }


DatabaseHandler.java:
package com.example.phonebookmcc;
 import android.content.ContentValues;
 import android.content.Context;
 import android.database.Cursor;
 import android.database.sqlite.SQLiteDatabase;
 import android.database.sqlite.SQLiteOpenHelper;
 public class DatabaseHandler extends SQLiteOpenHelper {
    SQLiteDatabase db;
    Context context;
    public DatabaseHandler(Context context) {
        super(context,"contacts",null,1);
       this.context=context;
        db=this.getWritableDatabase();
    }
    @Override
    public void onCreate(SQLiteDatabase db) {
        db.execSQL("create table phone(name TEXT,phoneNo text,email text,address text)");    }
    @Override
   public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
    }
    public int addContact(String name,String phone,String email,String address){
        ContentValues values=new ContentValues();
        values.put("name",name);
        values.put("phoneNo",phone);
        values.put("email",email);
        values.put("address",address);
        long rid=db.insert("phone",null,values);
        if(rid<0)
            return 0;
        else
            return 1;
    }
    public  String viewContact(){
        Cursor cursor=db.query("phone",new String[]{"name","phoneNo","email","address"},null,null,null,null,null);
        StringBuffer sb=new StringBuffer();
        cursor.moveToFirst();
        if(cursor.getCount()>0)
            do
           {
                sb.append("Name: "+cursor.getString(0)+"\nPhone No: "+cursor.getString(1)+"\nEmail: "+cursor.getString(2)+"\nAddress: "+cursor.getString(3)+
                        "\n--------------------------------------------\n");
            }while (cursor.moveToNext());
        return sb.toString();
    } }


//Timer
ANDROID: TIMER activity_main.xml
 <?xml version="1.0" encoding="utf-8"?>
  <LinearLayout  xmlns:android="http://schemas.android.com/apk/res/android"
     android:layout_width="match_parent"
     android:layout_height="match_parent"
     android:orientation="vertical"
     android:padding="10dp">
       <TextView
         android:id="@+id/tvCounter"
         android:layout_marginTop="150dp"
         android:layout_marginBottom="150dp"
         android:layout_width="wrap_content"
         android:layout_height="wrap_content"
         android:gravity="center"
         android:layout_gravity="center_horizontal"
         android:textSize="60sp"
         android:text="00:00:00"
         android:textStyle="bold"
         android:textColor="#4CAF50"/>
       <EditText
         android:id="@+id/etMinutes"
         android:layout_width="wrap_content"
         android:layout_gravity="center"
         android:layout_height="wrap_content"
         android:layout_marginLeft="10dp"
         android:layout_marginRight="10dp"
         android:hint="Enter Minutes!"
         android:padding="10dp"
         android:maxLength="4"
         android:inputType="number"
         android:textSize="26sp"
        android:gravity="center"
         android:textColor="#000000"
         android:textColorHint="#9E9E9E" />

       <LinearLayout
         android:layout_marginTop="30dp"
         android:orientation="horizontal"
         android:layout_width="fill_parent"
         android:gravity="center"
         android:padding="10dp"
         android:layout_gravity="center"
         android:layout_height="wrap_content">

           <Button
             android:id="@+id/btnStartStopTimer"
             android:layout_width="wrap_content"
             android:layout_height="wrap_content"
             android:layout_marginRight="10dp"
             android:padding="10dp"
             android:background="#009688"
             android:textColor="#ffffff"
             android:textSize="16sp"
             android:text="Start Timer" />
           <Button
             android:id="@+id/btnResetTimer"
             android:layout_width="wrap_content"
             android:layout_height="wrap_content"
            android:background="#009688"
             android:textColor="#ffffff"
             android:textSize="16sp"
             android:padding="10dp"
             android:layout_marginLeft="10dp"
             android:text="Reset Timer" />
     </LinearLayout>
    </LinearLayout>


MainActivity.java:
 package com.karanmadhu.mytimer;
    import androidx.appcompat.app.AppCompatActivity;
    import android.os.Bundle;
  import android.os.CountDownTimer;
  import android.view.View;
  import android.view.WindowManager;
  import android.widget.Button;
  import android.widget.EditText;
  import android.widget.TextView;
  import android.widget.Toast;
    import java.util.concurrent.TimeUnit;
    public class MainActivity extends AppCompatActivity {
       TextView tvCounter;
     EditText etMinutes;
     Button btnStartStopTimer, btnResetTimer;
     private static CountDownTimer countDownTimer;
       @Override
     protected void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
         setContentView(R.layout.activity_main);           // Hide status bar
  getWindow().addFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN) ;           // Hide action bar         getSupportActionBar().hide();
           tvCounter = findViewById(R.id.tvCounter);
         etMinutes = findViewById(R.id.etMinutes);
         btnStartStopTimer =  findViewById(R.id.btnStartStopTimer);
         btnResetTimer = findViewById(R.id.btnResetTimer);
           btnStartStopTimer.setOnClickListener(new  View.OnClickListener() {
             @Override
             public void onClick(View view) {
                 if (countDownTimer == null) {
                     String getMinutes =  etMinutes.getText().toString(); //Get minutes from editText                     //Check validation over editText
                     if (!getMinutes.equals("") &&  getMinutes.length() > 0) {
                         int noOfMinutes =  Integer.parseInt(getMinutes);
                         int milliseconds = noOfMinutes * 60 *  1000; //Convert minutes into milliseconds
                           countDownTimer = new  CountDownTimer(milliseconds, 1000) {
                             public void onTick(long  millisUntilFinished) {
                                long millis =  millisUntilFinished;
                                //Convert milliseconds into  hour, minute and seconds
                                 long hours =  TimeUnit.MILLISECONDS.toHours(millis);
                                 long minutes =  TimeUnit.MILLISECONDS.toMinutes(millis) -    TimeUnit.HOURS.toMinutes(hours);
                                 long seconds =  TimeUnit.MILLISECONDS.toSeconds(millis) -    TimeUnit.MINUTES.toSeconds(minutes);
                                 String hms =  String.format("%02d:%02d:%02d", hours, minutes, seconds);
                                 tvCounter.setText(hms);
                             }
                               public void onFinish() {
                                   tvCounter.setText("TIME'S  UP!!");
                                 countDownTimer = null;
                                 btnStartStopTimer.setText("Start  Timer");

                             }
                         }.start();
                         btnStartStopTimer.setText("Stop  Timer");//Change Text
                       } else
                         Toast.makeText(getApplicationContext(),
                                 "Please enter no. of Minutes.",
                                 Toast.LENGTH_SHORT).show();
                 }
                else {
                     countDownTimer.cancel();
                     countDownTimer = null;
                     btnStartStopTimer.setText("Start Timer");
                 }
             }
         });
           btnResetTimer.setOnClickListener(new  View.OnClickListener() {
             @Override
             public void onClick(View view) {
                 if (countDownTimer != null) {
                     countDownTimer.cancel();
                     countDownTimer = null;
                 }
                 btnStartStopTimer.setText("Start Timer");
                 tvCounter.setText("00:00:00");
             }
         });
     }
  }


///frequency reuse
mport java.util.Scanner;
class Cofrequency{
	public static void  main(String[] args) {
		int[][] arr = new int[11][11];

		int i,j,k;
		Scanner sc=new Scanner(System.in);
		System.out.print("Enter i: ");
		i=sc.nextInt();
		System.out.print("Enter j: ");
		j=sc.nextInt();

		int x,y;
		System.out.println("\nBefore");
		for(x=0;x<11;x++){
			for(y=0;y<11;y++){
				System.out.print(arr[x][y] + " ");
			}
			System.out.println();
		}
		arr[5][5]=2;
		arr[5+j][5+j+i]=1;
		arr[5-j][5+j+i]=1;
		arr[5+j][5-j-i]=1;
		arr[5-j][5-j-i]=1;
		arr[5-i-j-1][5]=1;
		arr[5+i+j+1][5]=1;

		System.out.println("\nAfter");
		for(x=0;x<11;x++){
			for(y=0;y<11;y++){
				System.out.print(arr[x][y] + " ");
			}
			System.out.println();
		}
		for(i=2;i<=8;i++)
			for(j=3;j<8;j++)
				if (arr[i][j]==0)
				arr[i][j]=1;
		System.out.println("\nCluster Formation");
		for(x=0;x<11;x++){
			for(y=0;y<11;y++){
				System.out.print(arr[x][y] + " ");
			}
			System.out.println();
		}

}
}


//fontandroid

XML FILE:
<?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/textView"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_margin="30dp"
        android:layout_marginBottom="8dp"
        android:layout_marginTop="160dp"
        android:gravity="center"
        android:text="Hello World!"
        android:textSize="25sp"
        android:textStyle="bold"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent"
        app:layout_constraintVertical_bias="0.214" />

    <Button
        android:id="@+id/button1"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_margin="20dp"
        android:layout_marginStart="16dp"
        android:gravity="center"
        android:text="Change font size"
        android:textSize="25sp"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent" />

    <Button
        android:id="@+id/button2"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_margin="20dp"
        android:layout_marginBottom="8dp"
        android:layout_marginTop="8dp"
        android:gravity="center"
        android:text="Change color"
        android:textSize="25sp"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toBottomOf="@+id/button1" />

</android.support.constraint.ConstraintLayout>

JAVA FILE:
package com.example.sharad.font;

import android.graphics.Color;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.TextView;

public class MainActivity extends AppCompatActivity {
    int ch=1;
    float font=30;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        final TextView t= (TextView) findViewById(R.id.textView);
        Button b1= (Button) findViewById(R.id.button1);
        b1.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                t.setTextSize(font);
                font = font + 5;
                if (font == 50)
                    font = 30;
            }
        });

        Button b2= (Button) findViewById(R.id.button2);

        b2.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                switch (ch) {
                    case 1:
                        t.setTextColor(Color.RED);
                        break;
                    case 2:
                        t.setTextColor(Color.GREEN);
                        break;
                    case 3:
                        t.setTextColor(Color.BLUE);
                        break;
                    case 4:
                        t.setTextColor(Color.CYAN);
                        break;
                    case 5:
                        t.setTextColor(Color.YELLOW);
                        break;
                    case 6:
                        t.setTextColor(Color.MAGENTA);
                        break;
                }
                ch++;
                if (ch == 7)
                    ch = 1;


            }
        });
    }
}


//graphical premitives
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:layout_width="match_parent"
   android:layout_height="match_parent"
   tools:context=".MainActivity">


   <ImageView
       android:id="@+id/image"
       android:layout_width="match_parent"
       android:layout_height="match_parent"
        />
</RelativeLayout>

MainActivity.java:
package com.example.basicprimitivesmcc;

import android.graphics.Bitmap;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.graphics.drawable.BitmapDrawable;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.widget.ImageView;

public class MainActivity extends AppCompatActivity {

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

       Bitmap bm = Bitmap.createBitmap(720,1280,Bitmap.Config.ARGB_8888);
       ImageView i = (ImageView)findViewById(R.id.image);
       i.setBackgroundDrawable(new BitmapDrawable(bm));
       Canvas canvas=new Canvas(bm);
       Paint paint=new Paint();
       paint.setColor(Color.RED);
       paint.setTextSize(50);
       canvas.drawRect(400,200,600,700,paint);//left top right bottom
       canvas.drawCircle(200,200,100,paint);//cx,cy,radius
       canvas.drawRect(50,800,300,1100,paint);
       canvas.drawLine(500,800,500,1100,paint);//startx,starty,stopx,stopy

   }
}


///gps
ANDROID : GPS Give permissions after installing apk in your phone
MainActivity.xml:
<?  xml version="1.0" encoding="utf-8"?>
<LinearLayout 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"
	android:orientation="vertical"    >

<TextView
        android:id="@+id/tvInfo"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"

        android:text="" />
    <Button
        android:id="@+id/btnShare"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="Share" />
 </LinearLayout>

 MainActivity.java:
package com.example.locationmcc;

 import android.Manifest;
 import android.content.Intent;
 import android.content.pm.PackageManager;
 import android.location.Address;
 import android.location.Geocoder;
 import android.location.Location;
 import android.support.annotation.NonNull;
 import android.support.annotation.Nullable;
 import android.support.v4.app.ActivityCompat;
 import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
 import android.view.View;
 import android.widget.Button;
 import android.widget.TextView;
 import android.widget.Toast;
 import com.google.android.gms.common.ConnectionResult;
 import com.google.android.gms.common.api.GoogleApiClient;
 import com.google.android.gms.common.api.GoogleApiClient.ConnectionCallbacks;
 import com.google.android.gms.common.api.GoogleApiClient.OnConnectionFailedListener;
 import com.google.android.gms.location.LocationServices;
 import java.io.IOException;
 import java.util.List;
 import java.util.Locale;

 public class MainActivity extends AppCompatActivity implements GoogleApiClient.ConnectionCallbacks, GoogleApiClient.OnConnectionFailedListener {
    TextView tvInfo;
    Button btnShare;
    GoogleApiClient gac;
    Location loc;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
	super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main  );
        tvInfo = findViewById(R.id.tvInfo  );
        btnShare = findViewById(R.id.btnShare  );
        GoogleApiClient.Builder builder = new GoogleApiClient.Builder(this);
        builder.addApi(LocationServices.API  );
        builder.addConnectionCallbacks(this);
        builder.addOnConnectionFailedListener(this);
        gac = builder.build();
        btnShare.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                Intent i = new Intent(Intent.ACTION_SEND  );
                i.setType("text/plain");
                i.putExtra(Intent.EXTRA_TEXT  , "My address is: " + tvInfo.getText().toString());
                startActivity(i);
            }
        });
    }

    @Override
    protected void onStart() {
       super.onStart();
        if (gac != null)
            gac.connect();
    }
    @Override
    protected void onStop() {
        super.onStop();
        if (gac != null) {
            gac.disconnect();
            //btnShare.setEnabled(false);
         }
    }
    @Override
    public void onPointerCaptureChanged(boolean hasCapture) {
    }
    @Override
    public void onConnectionFailed(@NonNull ConnectionResult connectionResult) {
        Toast.makeText  (this, "Connection Failed", Toast.LENGTH_SHORT  ).show();
    }
    @Override
    public void onConnected(@Nullable Bundle bundle) {
        if (ActivityCompat.checkSelfPermission
  (this, android.Manifest.permission.ACCESS_FINE_LOCATION ) != PackageManager.PERMISSION_GRANTED && ActivityCompat.checkSelfPermission
  (this, android.Manifest.permission.ACCESS_COARSE_LOCATION  ) != PackageManager.PERMISSION_GRANTED
  )
 {
            return;
        }
        loc = LocationServices.FusedLocationApi.getLastLocation(gac);
        if(loc != null){
            double lat = loc.getLatitude();
            double lon = loc.getLongitude();
            tvInfo.setText("Latitude: "+ lat+ " Longitude: "+ lon);
            Geocoder g = new Geocoder(this, Locale.ENGLISH  );
            try {
                List<android.location.Address> la = g.getFromLocation(lat, lon, 1); //number of results = 1
                 android.location.Address add = la.get(0);
                String msg = add.getCountryName() + " " +                        add.getAdminArea() + " " +                        add.getSubAdminArea() + " " +                        add.getLocality() + " " +                        add.getSubLocality() + " " +                        add.getThoroughfare() + " " +
                       add.getSubThoroughfare() + " " +                        add.getPostalCode();                tvInfo.setText(msg);
            }
 catch (IOException e) {
                e.printStackTrace();
            }
        }
        else{
           tvInfo.setText("Please enable GPS");
        }
    }
    @Override
    public void onConnectionSuspended(int i) {
        Toast.makeText  (this, "Connection Suspended "+CAUSE_NETWORK_LOST  , Toast.LENGTH_SHORT  ).show();
    }
 }


AndroidManifest.xml:
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
     package="com.example.locationmcc"> <uses-permission android:name="android.permission.ACCESS_FINE_LOCATION"/>
    <uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION"/>
     <uses-permission android:name="android.permission.INTERNET"/>
     <application
         android:allowBackup="true"
         android:icon="@mipmap/ic_launcher"
         android:label="@string/app_name"
         android:roundIcon="@mipmap/ic_launcher_round"
         android:supportsRtl="true"
         android:theme="@style/AppTheme">
         <activity android:name=".MainActivity">
             <intent-filter>
                 <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />
             </intent-filter>
         </activity>
         <meta-data
             android:name="com.google.android.geo.API_KEY"
             android:value="YOUR KEY HERE  "/>
     </application> </manifest>

Gradle: (Add this line) implementation 'com.google.android.gms:play-services:12.0.1'


/login form react native
import React, { Component } from 'react';
import { Alert, Button, TextInput, View, StyleSheet } from 'react-native';

export default class App extends Component {
  constructor(props) {
    super(props);

    this.state = {
      username: '',
      password: '',
    };
  }

  onLogin() {
    const { username, password } = this.state;

    Alert.alert('Credentials', `${username} + ${password}`);
  }

  render() {
    return (
      <View style={styles.container}>
        <TextInput
          value={this.state.username}
          onChangeText={(username) => this.setState({ username })}
          placeholder={'Username'}
          style={styles.input}
        />
        <TextInput
          value={this.state.password}
          onChangeText={(password) => this.setState({ password })}
          placeholder={'Password'}
          secureTextEntry={true}
          style={styles.input}
        />

        <Button
          title={'Login'}
          style={styles.input}
          onPress={this.onLogin.bind(this)}
        />
      </View>
    );
  }
}

const styles = StyleSheet.create({
  container: {
    flex: 1,
    alignItems: 'center',
    justifyContent: 'center',
    backgroundColor: '#ecf0f1',
  },
  input: {
    width: 200,
    height: 44,
    padding: 10,
    borderWidth: 1,
    borderColor: 'black',
    marginBottom: 10,
  },
});