How to select single checkbox in a recycler view with multiple checkboxes

Question

There are answers of this questions but none of them solved my problem .Below is my code .

  public class QuizAdapter extends RecyclerView.Adapter<QuizAdapter.MyViewHolder> {
Context context;
private List<Quiz_G_S> quiz_g_sList = null;
int selectedPosition = -1;


public QuizAdapter(Context context, List<Quiz_G_S> list) {
    this.context = context;
    this.quiz_g_sList = list;
}


@Override
public QuizAdapter.MyViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
    View itemView = LayoutInflater.from(parent.getContext())
            .inflate(R.layout.quiz_single_row, parent, false);

    return new MyViewHolder(itemView);

}

@Override
public void onBindViewHolder(final QuizAdapter.MyViewHolder holder, int position) {

    final int pos = position;

    holder.answers.setText(quiz_g_sList.get(pos).getMCQ());

    holder.checkBox.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener() {
        @Override
        public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {

            quiz_g_sList.get(pos).setChecked(true);

        }
    });

    if (quiz_g_sList.get(pos).isChecked()) {
        holder.checkBox.setChecked(true);
        notifyDataSetChanged();

    } else {
        holder.checkBox.setChecked(false);

    }





}


@Override
public int getItemCount() {
    return quiz_g_sList.size();
}

public class MyViewHolder extends RecyclerView.ViewHolder {

    TextView answers;
    CheckBox checkBox;

    public MyViewHolder(View v) {
        super(v);

        answers = (TextView) v.findViewById(R.id.quiz_adap_ans);
        checkBox = (CheckBox) v.findViewById(R.id.quiz_adap_check);

    }
}

Above is my adapter code.

This is my Quiz_G_S class

public class Quiz_G_S {


String MCQ;
int Rank;
boolean checked;

public boolean isChecked() {
    return checked;
}

public void setChecked(boolean checked) {
    this.checked = checked;
}

public String getMCQ() {
    return MCQ;
}

public void setMCQ(String mcq) {
    this.MCQ = mcq;
}

public int getRank() {
    return Rank;
}

public void setRank(int rank) {
    this.Rank = rank;
}

}

What i want to do is if i check a checkbox then all checkboxes will set unchecked except the one I checked There is an error on notifyDataSetChanged. I guess the logic is right but i don't know how to refresh checkbox state.The only thing I know is notifyDataSetChanged is there any other method to refresh or is there any workaround for this problem

score 1 · Answer 1 · answered Sep 29 '17 at 13:06

try below code:

Define one more Object in your Quiz_G_S Class boolean isChecked
Get the position of checked CheckBox

selectedPosition = holder.getAdapterPosition();

Reset all other objects of List like below:

for (int i=0; i<list.size ; i++) 
{  
  if (selectedPosition==i)  
     list.get(i).setIsChecked(true); 
  else     
     list.get(i).setIsChecked(false);
}

call QuizAdapter.this.notifyDataSetChanged();.

In last, check selected check box like below:

if (list.get(position).getIsChecked()) 
{
   holder.checkBox.setChecked(true);
} else {
  holder.checkBox.setChecked(false);
}

yogesh lokhande · Answer 2 · 2017-09-29T12:56:12.943

0

Instead of

 selectedPosition = holder.getAdapterPosition();

maintain a flag inside your object class which will be set on Check of particular checkbox suppose "checked" is your flag that you have created in your object class then

on check change listener set it to true

if (isChecked) {
    holder.checkBox.setChecked(true);

} else {
    holder.checkBox.setChecked(false);

}

EDIT

 if (quiz_g_sList.get(pos).isChecked) {
        holder.checkBox.setChecked(true);

    } else {
        holder.checkBox.setChecked(false);

    }

UPDATE

change your object class to this

 public class Quiz_G_S {

        String MCQ;
        int Rank;
        boolean checked;

        public boolean isChecked() {
            return checked;
        }

        public void setChecked(boolean checked) {
            this.checked = checked;
        }

        public String getMCQ() {
            return MCQ;
        }

        public void setMCQ(String mcq) {
            this.MCQ = mcq;
        }

        public int getRank() {
            return Rank;
        }

        public void setRank(int rank) {
            this.Rank = rank;
        }
    }

edited Sep 29 '17 at 12:56

answered Sep 29 '17 at 12:21

yogesh lokhande

1,245
1
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20

but how will i refresh the state of checkboxes? – dhami_ji Sep 29 '17 at 12:25
what is setChecked (true) in quiz_g_sList.get(pos).setChecked(true);.Is this a method which i have to create? – dhami_ji Sep 29 '17 at 12:34
As i told you, you need to create flag in your object class i.e. Quiz_G_S – yogesh lokhande Sep 29 '17 at 12:35
Sorry but i didn't get it .As i am new to android .Can u plz explain a bit more – dhami_ji Sep 29 '17 at 12:36
can you provide me your class named as Quiz_G_S – yogesh lokhande Sep 29 '17 at 12:38
thanks for the help but still my code working remains the same. I am guessing that the data needs to be refreshed – dhami_ji Sep 29 '17 at 12:48
did you called notifyDataSetChanged(); after setting it true – yogesh lokhande Sep 29 '17 at 12:54
whats the issue now, can you update your question with your updated code? – yogesh lokhande Sep 29 '17 at 13:00
issue is all the checkboxes are checked, what i want is only a single checkbox is checked. And i have edited my code plz have a look – dhami_ji Sep 29 '17 at 13:02
please check your arraylist and then go through my code you did it wrong way – yogesh lokhande Sep 29 '17 at 13:06

score 0 · Answer 3 · answered Sep 29 '17 at 12:28

I have implemented like this, where i got output.

if(view == null) {

        view = inflater.inflate(R.layout.todo_checkbox_adapter_layout, parent, false);
        holder = new ViewHolder();
        holder.todoItemTextView = (TextView) view.findViewById(R.id.item_tv);
        holder.checkedTextView = (CheckBox) view.findViewById(R.id._item_checkbox);
        view.setTag(holder);
    } else {
        holder = (ViewHolder) view.getTag();
    }
    holder.todoItemTextView.setTag("" + position);
    holder.checkedTextView.setChecked(displayModel.isFinished());

    holder.checkedTextView.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener() {
        @Override
        public void onCheckedChanged(CompoundButton compoundButton, boolean isChecked) {
            try {
                String tag = (String) holder.todoItemTextView.getTag();
                int pos = Integer.parseInt(tag);
                todoItemBeanList.get(pos).setFinished(isChecked);
            } catch (NumberFormatException e) {
                e.printStackTrace();
            }
        }
    });

score 0 · Answer 4 · answered Sep 29 '17 at 13:03

What do you have to do:

Pass checked position to Activity/Fragment/Presenter (Implement click/checkChanged listener). Examples can be found here: RecyclerView onClick
Save position of checked item into a variable (say int selectedPosition).
Then update previously checked item on each click/check:

if (position != selectedPosition) { // user selected another item so previous one should be updated adapter.notifyItemChanged(selectedPosition); selectedPosition = position; }

How to select single checkbox in a recycler view with multiple checkboxes

4 Answers4