How to limit the choice of a flag in the list?

Question

friends

I want to limit the choice of a flag in the list of androids, for example, you need to select only 3 flags, otherwise it should give an error message.

the user can select any three checkboxes from the list; someone will tell me how to achieve this? here is my adapter

public class AdapterContacts extends BaseAdapter { private LayoutInflater mInflater; public Context context; public static List<myContacts> contacts; public AdapterContacts(Context context,List<myContacts> list) { mInflater = LayoutInflater.from(context); this.context = context; contacts= list; } public View getView(final int position, View convertView, ViewGroup parent) { ViewHolder holder; if (convertView == null) { convertView = mInflater.inflate(R.layout.list_contacts, null); holder = new ViewHolder(); holder.contactName = (TextView) convertView.findViewById(R.id.contactName); holder.contactNumber = (TextView) convertView.findViewById(R.id.contactNumber); holder.checkBox = (CheckBox) convertView.findViewById(R.id.checkBox); convertView.setTag(holder); } else { holder = (ViewHolder) convertView.getTag(); } myContacts contact = getItem(position); holder.checkBox.setOnCheckedChangeListener(new OnCheckedChangeListener() { @Override public void onCheckedChanged(CompoundButton checkboxView, boolean isChecked) { myContacts c = (myContacts) checkboxView.getTag(); c.setSelected(isChecked); // to put that check of selection limit with error } }); holder.checkBox.setTag(contact); holder.checkBox.setChecked(contact.isSelected()); holder.contactName.setText(contact.getContactName()); holder.contactNumber.setText(contact.getPhoneNumber()); return convertView; } @Override public int getCount() { return contacts.size(); } @Override public myContacts getItem(int position) { return contacts.get(position); } @Override public long getItemId(int arg0) { return 0; } class ViewHolder { TextView contactName; TextView contactNumber; CheckBox checkBox; } } 

Any help would be appreciated.

Answer 1

finally I solved this problem :) where globalInc is a global variable with a default value of 0

 holder.checkBox.setOnCheckedChangeListener(new OnCheckedChangeListener() { @Override public void onCheckedChanged(CompoundButton checkboxView, boolean isChecked) { myContacts c = (myContacts) checkboxView.getTag(); if(isChecked) { globalInc++; } else if(!isChecked) { globalInc--; } if(globalInc >= 4)// it will allow 3 checkboxes only { Toast.makeText(context, "Error = " + globalInc, Toast.LENGTH_LONG).show(); checkboxView.setChecked(false); globalInc--; } else { c.setSelected(isChecked); } System.out.println(" --------------- "+globalInc); } }); 

Answer 2

Take the static variable count int and increase it using this condition

holder.checkBox.isChecked (), if true, then increment the counter then check count> 3, then display a popup to the user

Hope this helps.

Answer 3

 int globalInc = 0; boolean isCheckGlobal = false; ArrayList<Integer> checkings = new ArrayList<Integer>(); @Override public View getView(final int position, View convertView, ViewGroup parent) { ViewHolder viewHolder = null; if (convertView == null) { LayoutInflater inflator = context.getLayoutInflater(); convertView = inflator.inflate(R.layout.list_inner, null); viewHolder = new ViewHolder(); viewHolder.friendName = (TextView) convertView .findViewById(R.id.friendName); viewHolder.checkbox = (CheckBox) convertView .findViewById(R.id.checkbox); final MyAdapterSecond objectMyAdapter = new MyAdapterSecond(); viewHolder.checkbox.setOnClickListener(new OnClickListener() { @Override public void onClick(View v) { // TODO Auto-generated method stub int getPositionInClick = (Integer) v.getTag(); if (isCheckGlobal == false) { if (checkings.contains(getPositionInClick)) { globalInc--; checkings.remove(checkings.indexOf(getPositionInClick)); } else { objectMyAdapter.getCheck(false); } } else if (isCheckGlobal == true) { if (checkings.size() < 4) { globalInc++; } } } }); viewHolder.checkbox .setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener() { @Override public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) { int getPosition = (Integer) buttonView.getTag(); list.get(getPosition).setSelected( buttonView.isChecked()); callCheck(buttonView, "hi1"); if (checkings.size() > 4 { Toast.makeText(context, "Error = " + globalInc, Toast.LENGTH_LONG).show(); objectMyAdapter.setCheck(buttonView); isCheckGlobal = false; } else { buttonView.setSelected(isChecked); if (isChecked && (!checkings.contains(getPosition))) { checkings.add(getPosition); } else if(!isChecked){ if(checkings.contains(getPosition)){ checkings.remove(checkings.indexOf(getPosition)); } } isCheckGlobal = true; } } }); convertView.setTag(viewHolder); convertView.setTag(R.id.friendName, viewHolder.friendName); convertView.setTag(R.id.checkbox, viewHolder.checkbox); } else { viewHolder = (ViewHolder) convertView.getTag(); } viewHolder.checkbox.setTag(position); // This line is important. viewHolder.friendName.setText(list.get(position).getname()); viewHolder.checkbox.setChecked(list.get(position).isSelected()); return convertView; } class MyAdapterSecond { CompoundButton buttonView; public void setCheck(CompoundButton buttonView) { this.buttonView = buttonView; } public void getCheck(boolean flag) { this.buttonView.setChecked(flag); } } 

Answer 4

Try the following:

 public class AccountListAdapter extends BaseAdapter { @SuppressWarnings("unused") private final static String TAG = AccountListAdapter.class.getSimpleName(); private Context context; private List<Account> rowItems; private int selectedItemCounter = 0; private final int limit; public AccountListAdapter(Context context, List<Account> items, int limit) { this.context = context; this.rowItems = items; this.limit = limit; } public View getView(final int position, View convertView, ViewGroup parent) { LayoutInflater mInflater = (LayoutInflater) context .getSystemService(Activity.LAYOUT_INFLATER_SERVICE); final Account rowItem = (Account) getItem(position); convertView = mInflater.inflate(R.layout.account_selection_item, null); TextView tv = (TextView) convertView.findViewById(R.id.textView); ToggleButton tb = (ToggleButton) convertView .findViewById(R.id.toggleButton); tb.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener() { @Override public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) { if (isChecked && !rowItem.isSelected()) { if (selectedItemCounter >= limit) { Toast.makeText(context, "can't be more" + selectedItemCounter, Toast.LENGTH_SHORT).show(); buttonView.setChecked(false); return; } rowItem.setSelected(true); selectedItemCounter++; } else if (!isChecked && rowItem.isSelected()) { rowItem.setSelected(false); selectedItemCounter--; } } }); tv.setText(rowItem.getDevId()); tb.setChecked(rowItem.isSelected()); return convertView; } @Override public int getCount() { return rowItems.size(); } @Override public Object getItem(int position) { return rowItems.get(position); } @Override public long getItemId(int position) { return rowItems.indexOf(getItem(position)); } } 

tried to improve my code using ViewHolder template but failed. if anyone has a better idea please let me know.