Question

I am doing application and I need to dispaly some images in a gridview. I need to display images in that gridview randomly. So here I taken one integer array like mThumbIds[] in that I add all images, then I take arraylistl like solutionList then that mThumbIds[] intrgerarray.

I added into solutionList array.then i apply random function to that solutionList arrat then agaain i add solutionList array into one integer array like “randomNumbers[]” then finally i add that randomNumbers[] array to gridview i get random images but my probem is in gridview repated images coming,but i dont want repeted images. in mThumbIds[] i am not given repted images.please any one suggest me.

     ImageAdapter .class:
          public class ImageAdapter extends BaseAdapter {
         private Context mContext;

public ImageAdapter(Context c) {

    // TODO Auto-generated constructor stub
    mContext = c;
}

public int getCount() {
    // TODO Auto-generated method stub
    return mThumbIds.length;
}

public Object getItem(int position) {
    // TODO Auto-generated method stub
    return null;
}

public long getItemId(int position) {
    // TODO Auto-generated method stub
    return 0;
}

public View getView(int position, View convertView, ViewGroup parent) {
    ImageView imageView;
int unique=0;
    if (convertView == null) { // if it's not recycled, initialize some attributes
        imageView = new ImageView(mContext);
        imageView.setLayoutParams(new GridView.LayoutParams(85, 85));
        imageView.setScaleType(ImageView.ScaleType.CENTER_CROP);
        imageView.setPadding(8, 8, 8, 8);
    } else {
        imageView = (ImageView) convertView;
    }
      Collections.shuffle(solutionList);
      Integer[] randomNumbers=(Integer[])solutionList.toArray();
    imageView.setImageResource(randomNumbers[unique]);
    unique++;
    return imageView;
}
private Integer[] mThumbIds={R.drawable.a,R.drawable.bb,R.drawable.cc,R.drawable.dd,R.drawable.ee,R.drawable.ff,R.drawable.galley,R.drawable.gg};
  List<Integer> solutionList = Arrays.asList( mThumbIds);

}

Answer 1

A solution here is to store indexes of items that are already used in a special ArrayList. And also I’d recommend you using the java.util.Random class instead of shuffling the array everytime. The code will look like this:

ArrayList<Integer> usedIndexes = new ArrayList<Integer>();
        int index;
        do {
            index = new Random().nextInt(mThumbIds.length);
        } while (usedIndexes.contains(index));
            imageView.setImageResource(randomNumbers[index]);
        usedIndexes.add(index);

Hope this helps.