Amazing Random Class Variables

Playing Android Games is an amazing experience as every time one plays the game, s/he comes across new obstacles, new villains of different sizes, different colors, different numbers, new backgrounds and much more. This feature retains the interest of the player in the game by preventing the boredom which is created when the player plays the games which loads the same components every time.

This amazing feature is achieved with the help of Random class variables. These variables generate random values restricted to the limit specified every time they are executed.

Let us learn the use of Random class variables with simple example. Let us create an Android application which will generate random colors in the 3 x 3 grid every time the “Play” button is pressed.

Code:

package com.example.randomcolorsgenerator;

import java.util.Random;
import android.os.Bundle;
import android.app.Activity;
import android.graphics.Color;
import android.view.View;
import android.widget.*;

public class MainActivity extends Activity {

TextView t[] = new TextView [9];
Button b1;
int i,red,green,blue;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        t[0] = (TextView)findViewById(R.id.tv1);
        t[1] = (TextView)findViewById(R.id.tv2);
        t[2] = (TextView)findViewById(R.id.tv3);
        t[3] = (TextView)findViewById(R.id.tv4);
        t[4] = (TextView)findViewById(R.id.tv5);
        t[5] = (TextView)findViewById(R.id.tv6);
        t[6] = (TextView)findViewById(R.id.tv7);
        t[7] = (TextView)findViewById(R.id.tv8);
        t[8] = (TextView)findViewById(R.id.tv9);
        b1 = (Button)findViewById(R.id.button);
   
            b1.setOnClickListener(new View.OnClickListener() {
               
                @Override
                public void onClick(View v) {
                    // TODO Auto-generated method stub
                    try{
                    Random r = new Random();
                    for(i=0;i<9;i++){
                        red = r.nextInt(256);
                        green = r.nextInt(256);
                        blue = r.nextInt(256);
                        t[i].setBackgroundColor(Color.rgb(red,green,blue));
                        t[i].setText(red+","+green+","+blue);
                    }
                    }
                   
                    catch(Exception e){}
                }
           
            });
  
    }
   
}

Layout file:

Click to view the XML file

Snapshots:

Click here to download the apk file

Are you a Java Programmer – If yes, aren’t you an Android Developer?

Developing Android Applications is easier if you are a java programmer. Android Developer Tools comes with a pack of numerous classes which enables you to develop Android Applications. Before starting you should have the basic idea about how you would set up your android development environment. You will require:

• Java JDK
• Eclipse IDE
• Android ADT
• Android SDK

 I recommend Android Application Development Tutorials playlist (200 videos) by thenewboston on YouTube to learn developing android applications:

               

 https://www.youtube.com/playlist?list=PL2F07DBCDCC01493A

Here you will learn about:

• Setting up your android development environment in detail
• Layouts
• Use of various inbuilt classes and its methods

And much more..!  

Solution to the problem faced while syncing data with excel using java applet

In previous posts, we saw java programs in which we used applet to sync the entered data in the excel sheet. But when you run the program, you would face problem while writing the data to the file and opening of the file using applet's button. So add:

grant{
permission java.security.AllPermission;
}

statement in java.policy (C:\Program Files\Java\jdk1.8.0_05\jre\lib\security)
file.