Making random image appear behind another image

Question

So, I am making a game, but I am pretty much a beginner in Android Studio. I've tried to search for this, but didn't find anything I really wanted.

So, I researched on how to make an image disappear when tapped, and didn't really find how to do so, therefore that's the first thing I want to happen.

So, once that's done, I want another image to appear behind it, but the image should be randomly chosen from a group of 5 images.

That's it, I apologise for not having any code tried out or anything, as like I said I'm still a beginner. Please help me soon.

Thanks in advance.

Answer 1

First take an image array of drawables e.g.

int[] imgArray = {
    R.drawable.img1,
    R.drawable.img2,
    R.drawable.img3,
    R.drawable.img4,
    R.drawable.img5
}

//random number between 1 to 5, in your case max=5, min =1
int randomNum = rand.nextInt((max - min) + 1) + min;

yourImageView.setBackgroundResource(imgArray[randomNum])

If you just want to change the previous image you don't have to dissapear first one. Just set the new image in that ImageView then automatically it will override.

However you can make an ImageView Visible, Invible or Gone by setting the following property

yourImageView.setVisibility(View.INVISIBLE);
yourImageView.setVisibility(View.GONE);

Answer 2

Assuming your 5 images are in drawable folder,

1. int img_arr[] = {R.id.img1, R.id.img2, ...};

2. set your image to imageview by using:

   imageview.setOnClickListener(new OnClickListener() {
      public void onClick(View v)
       {
           int a = random.nextInt(5); 
           //fade-in animation code
           imageview.setImageResource(0);
           //fade-out animation code
           imageview.setImageResource(img_array[a]);
   
       }
   

for animation, refer this link: Link

Answer 3

First take an image array of drawables like in Kunu's Answer e.g.

int[] imgArray = {
    R.drawable.img1,
    R.drawable.img2,
    R.drawable.img3,
    R.drawable.img4,
    R.drawable.img5
}

And for your first question,

1.How to make the image disappear when tapped

Consider you have an ImageView called img1 inside a RelativeLayout rl

We'll set an onClickListener to it like

img.setOnClickListener(new View.OnClickListener(View v)
{
v.setVisibility(View.INVISIBLE)
});

2.Make another Image appear behind it

call this function while passing the RelativeLayout like

randomBg(rl);

The randomBg function:

public void randomBg(RelativeLayout rl)
    {
    //random number between 1 to array limit
   /* int randomNum = rand.nextInt((minRange - maxRange) + 1) + minRange;
      Can be simplified as below*/

    int randomNum =rand.nextInt((0-imgArray.length)+1)+0;    
    rl.setBackgroundResource(imgArray[randomNum])
    }

To sum it up use the above code in an Activity like this

import android.app.Activity;
import android.os.Bundle;
import android.view.View;
import android.widget.ImageView;
import android.widget.RelativeLayout;

import com.mobilityeye.knowyourcustomer.R;

import java.util.Random;

/**
 * Created by PS on 1/4/2016.
 */
public class MyActivity extends Activity {
    RelativeLayout rl;
    ImageView imgView;
    int[] imgArray = {
            R.drawable.img1,
            R.drawable.img2,
            R.drawable.img3,
            R.drawable.img4,
            R.drawable.img5
    };
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.my_layout);
        rl=(RelativeLayout) findViewById(R.id.my_relative_layout);
        imgView=(ImageView) findViewById(R.id.my_image_view);
        imgView.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                v.setVisibility(View.INVISIBLE);
                //If you want to set Image at relativelayout
                randomBg(rl);
            }
        });
    }
    public void randomBg(RelativeLayout rl)
    {
        //random number between 1 to array limit
       /* int randomNum = rand.nextInt((minRange - maxRange) + 1) + minRange;
          Can be simplified as below*/
        Random rand = new Random();
        int randomNum =rand.nextInt((0-imgArray.length)+1)+0;
        rl.setBackgroundResource(imgArray[randomNum])
    }


}