Bahaaib

Add the following lines to onCreate method..

SharedPreferences sharedPreferences = this.getSharedPreferences("package name", Context.MODE_PRIVATE); //let the mode private to prevent 
//..any other App to access into it
sharedPreferences.edit().putString("variable_name", "variable_value").apply(); //@ putString() it could be any other variable type.

String variable_name = sharedPreferences.getString("variable_name",""); //"" refers to a default value for variable_name in case there wasn't

Bahaaib

package com.example.robpercival.locationdemo;

import android.app.Activity;
import android.content.Context;
import android.location.Criteria;
import android.location.Location;
import android.location.LocationListener;
import android.location.LocationManager;
import android.os.Bundle;
import android.util.Log;

Bahaaib

.
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protected void onPostExcute(String result){  // A Function to work in background and have the permission to change in UI simultaneously
  super.onPostExcute(result);
   try{
     JSONObject jsonObject = new  JSONObject(result);
     String weatherInfo = jsonObject.getString("weather");
     

Bahaaib

import java.util.Arrays;
import java.util.Pattern;
import java.util.Matcher;

public class HelloWorld {
  public static main (String[] args){
    String mystring = "Mississippi";
    String [] splitter = mystring.split("s"); // to split the phrase to words depends on a specific letter
    
    String riverPart = mystring.substring(2, 5); // to prints the letters starting from letter 2 to 5 "which is not including"

Bahaaib

public class DownloadTask extends AsyncTask<String, Void, String>{
  @Override
  protected String doInBackground(String... urls){
   String result = ""; // send Link to Method
   URL url;           // initialize URL variable
   HttpURLConnection urlConnection = null;  // initialize HttpURLConnection which later will be responsible for establishing Conn.
   try{
     url = new URL(urls[0]); //calling (urls member) number 0 from the (String...)
     urlConnection = (HttpURLConnection).openConnection(); // initialize the connection to the URL
     InputStream in = urlConnection.getInputStream(); // connecting the HTML page to the input stream

Bahaaib

final Handler handler = new Handler(); // A handler is a way used to run the code every certain delayed time
Runnable run  = new Runnable (){ // A Runnable is the that code
  @Override 
   public void run (){ // An override fuction describe exactly the action to be taken within that time
     
     //Insert a code to be run every certain "delayed time" 
     
     handler.postDelayed (this, 1000); // initialize the handler delayer for 1000msec= 1 second 
   }
   

Bahaaib

ListView myList = (ListView) findViewById(R.id.mylist)
ArrayList<String> myFamily = new ArrayList<String>();

myFamily.add("XXX"); // adding new items
myFamily.add("YYY");

// OR ArrayList<String> myFamily = new ArrayList<String>(asList"XXX", "YYY");

ArrayAdapter<String> arrayAdapter = new ArrayAdapter<String>(this, android.id.simple_list_item_1, myFamily);

Bahaaib

// Insert the following lines below your package name

import android.os.Bundle;
import android.support.design.widget.FloatingActionButton;
import android.support.design.widget.Snackbar;
import android.support.v7.app.AppCompatActivity;
import android.support.v7.widget.Toolbar;
import android.view.View;
import android.view.Menu;
import android.view.MenuItem;

Bahaaib

public class MainActivity extends ActionBarActivity {

    class Number {
                double x;
                String message = "";

                public void numTest() {


                    {