为什么我的列表视图总是删除列表中的最后一个视图

Question

I am adding Values to array and adapter and when i delete the specific item form listview it delete from arraylist perfectly but its delete the last view its mean if i have

a
b
c
d
e

when i delete b ....the e view is gones why...then the list is

a
b
c
d

I worked on this from last 2 week but i cannot find the error in this help me. Please Please Please Please

public class Home extends AppCompatActivity {

    Button addMoreBtn,checkoutBtn;
    MedicineBean medicineBean;
    //CustomAdapter customAdapter;
    ArrayList<MedicineBean> medOrderList;
    //<MedicineBean> medOrderList1;
    MyDBHandler db;
    ListView listView;
    int cust_id;
    EditText med_nameET, med_potencyET, med_qtyET;
    ImageButton increaseQty,decreaseQty;
    HomeListViewHandler homeListViewHandler;
    private ArrayAdapter<MedicineBean> adapter;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_home);
        String session_exp = SessionUtil.getSessionExpire(Home.this);
        if(Constants.LOGGING)
            Toast.makeText(getApplicationContext(),"Session Exp = "+session_exp+" Today Date "+new DateAndTimeUtil().getCurrentDate(),Toast.LENGTH_LONG).show();

        //30 days session expire checker
        if(session_exp.matches(new DateAndTimeUtil().getCurrentDate())){
            SessionUtil.setSignout(Home.this);
            Toast.makeText(getApplicationContext(),"Session has been expired due to 30 days limit exceeded",Toast.LENGTH_LONG).show();
            Intent intent = new Intent(Home.this, SignIn.class);
            intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK | Intent.FLAG_ACTIVITY_CLEAR_TASK);
            startActivity(intent);
        }
        //first check, Is user LOGGED IN  or not
        else if(SessionUtil.isLoggedIn(Home.this)) {

            Toolbar toolBar = (Toolbar) findViewById(R.id.easymed_toolbar);
            setSupportActionBar(toolBar);
            toolBar.setTitle(getResources().getString(R.string.home));
            DrawerUtil.getDrawer(this, toolBar);

            addMoreBtn      = (Button) findViewById(R.id.addtoList);
            checkoutBtn     = (Button) findViewById(R.id.checkOutBtn);
            listView        = (ListView) findViewById(R.id.medListView);
            med_nameET      = (EditText) findViewById(R.id.frstSingleItemET);
            med_potencyET   = (EditText) findViewById(R.id.scndSingleItemET);
            med_qtyET       = (EditText) findViewById(R.id.thrdSingleItemTV);
            increaseQty=(ImageButton) findViewById(R.id.increaceImgBtn);
            decreaseQty=(ImageButton) findViewById(R.id.decreaseImgBtn) ;
            medOrderList    = new ArrayList<MedicineBean>();
            //medOrderList1    = new ArrayList<MedicineBean>();
            cust_id         = SessionUtil.getCustomerId(Home.this);
            medicineBean    = new MedicineBean();
            db              = new MyDBHandler(Home.this);
            //customAdapter   = new CustomAdapter();
            adapter=new CustomAdapter(this,0,medOrderList);
            listView.setAdapter(adapter);


            increaseQty.setOnClickListener(new View.OnClickListener() {
                @Override
                public void onClick(View view) {
                    if(Constants.LOGGING)
                        System.out.println("Increment Btn pressed");
                    int val = Integer.parseInt(med_qtyET  .getText().toString());
                    val=val+1;
                    String str = Integer.toString(val);
                    med_qtyET  .setText(str);

                }
            });

           decreaseQty.setOnClickListener(new View.OnClickListener() {
                @Override
                public void onClick(View view) {
                    int val = Integer.parseInt(med_qtyET  .getText().toString());
                    if(val>0) {
                        val = val-1;
                        String str = Integer.toString(val);
                        med_qtyET.setText(str);
                    }

                }
            });
            checkoutBtn.setOnClickListener(new View.OnClickListener() {
                @Override
                public void onClick(View view) {
                    //add new medicines in local DB
                    int count = 0;

                    for (int i = 0; i < medOrderList.size(); i++) {

                        String name             = medOrderList.get(i).getMediceneName();
                        String potency=medOrderList.get(i).getMedicenePotency();
                        String qty = medOrderList.get(i).getMediceneQty();

                        if (!name.matches("") && !potency.matches("") && !qty.matches("")) {

                            //Check if medicine with same potency available in DB then quantity of medicine add
                            Cursor cursor = db.getMedByNameAndPotency(cust_id,name,potency);
                            if(cursor.getCount()>0)
                            {
                                cursor.moveToNext();
                                String qtyInDB      = cursor.getString(0);
                                int qtyInDBInt      = Integer.parseInt(qtyInDB);
                                int getQtyFromET    = Integer.parseInt(qtyInDB);
                                int resultOfSumQty  = getQtyFromET  +   qtyInDBInt;
                                db.updateMedQTY(cust_id,name,potency,resultOfSumQty);
                            }
                            //add new medicine
                            else if (db.addUsersMed(cust_id, name, potency, qty) != -1) {
                                medicineBean.setCust_id(cust_id);
                                medicineBean.setMediceneName(name);
                                medicineBean.setMedicenePotency(potency);
                                medicineBean.setMediceneQty(qty);
                                medOrderList.set(i, medicineBean);
                                //Log.i(Constants.TAG,medOrderList.get(i).toString());
                                count++;
                            }
                        }

                    }
                    if (count > 0) {
                        Toast.makeText(getApplicationContext(), "Medicines added successfully.", Toast.LENGTH_SHORT).show();
                    } else {
                        Toast.makeText(getApplicationContext(), "Medicines not added into cart.", Toast.LENGTH_SHORT).show();
                    }
                    Intent intent = new Intent(Home.this, Cart.class);
                    startActivity(intent);

                }
            });

            addMoreBtn.setOnClickListener(new View.OnClickListener() {
                @Override
                public void onClick(View view) {


                    if (!med_nameET.getText().toString().matches("") && !med_potencyET.getText().toString().matches("")
                            && !med_qtyET.getText().toString().matches("0")) {

                        medOrderList.add(new MedicineBean(cust_id,med_nameET.getText().toString(),med_potencyET.getText().toString(),med_qtyET.getText().toString()));
                        med_nameET.setText("");
                        med_potencyET.setText("");
                        med_qtyET.setText("0");
                        adapter.notifyDataSetChanged();

                        Log.d("data",String.valueOf(medOrderList.size()));

                    }
                    else
                    {
                        Toast.makeText(getApplicationContext(), "Please fill all empty fields then press \'Add More\' button", Toast.LENGTH_SHORT).show();
                    }

                }
            });

        }
        else
        {
            Intent intent = new Intent(Home.this, SignIn.class);
            intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK | Intent.FLAG_ACTIVITY_CLEAR_TASK);
            startActivity(intent);
        }



    }












    private class ListViewHolder{

        EditText medET;
        EditText potencyET;
        EditText incrOrDecET;
        ImageButton cancelBtn;


    }

    class CustomAdapter extends ArrayAdapter<MedicineBean> {
        private Context context;
        private List<MedicineBean> medicineBeanList;
        ListViewHolder listViewHolder;

        public CustomAdapter(Context context, int resource, ArrayList<MedicineBean> objects) {

            super(context, resource, objects);
            this.context = context;
            this.medicineBeanList = objects;
        }

        @Override
        public int getCount() {
            return medicineBeanList.size();
        }

        @Override
        public MedicineBean getItem(int i) {
            return medicineBeanList.get(i);
        }

        @Override
        public long getItemId(int i) {
            return i;
        }

        @Override
        public View getView(final int i, View view, ViewGroup viewGroup) {


            if(view==null) {
                view = getLayoutInflater().inflate(R.layout.single_item, null);
                listViewHolder = new ListViewHolder();
                listViewHolder.medET = (EditText) view.findViewById(R.id.mediceNameInHomeList);
                listViewHolder.potencyET = (EditText) view.findViewById(R.id.medicePotencyInHomeList);
                listViewHolder.incrOrDecET = (EditText) view.findViewById(R.id.mediceQtyInHomeList);
                listViewHolder.cancelBtn = (ImageButton) findViewById(R.id.homeCnclBtn);
                listViewHolder.medET.setEnabled(false);
                listViewHolder.potencyET.setEnabled(false);
                listViewHolder.incrOrDecET.setEnabled(false);
                view.setTag(listViewHolder);


                listViewHolder.medET.setText(medicineBeanList.get(i).getMediceneName());
                listViewHolder.potencyET.setText(medicineBeanList.get(i).getMedicenePotency());
                listViewHolder.incrOrDecET.setText(medicineBeanList.get(i).getMediceneQty());

                listViewHolder.cancelBtn.setOnClickListener(new View.OnClickListener() {
                    @Override
                    public void onClick(View v) {
                        try {


                            adapter.remove(medicineBeanList.get(i));
                            adapter.notifyDataSetChanged();
                            /*for (int pos = 0; pos < medOrderList.size(); pos++)
                            {

                                listViewHolder.medET.setText(medOrderList.get(pos).getMediceneName());
                                listViewHolder.potencyET.setText(medOrderList.get(pos).getMedicenePotency());
                                listViewHolder.incrOrDecET.setText(medOrderList.get(pos).getMediceneQty());
                                //adapter.add(new MedicineBean(medOrderList.get(pos).getCust_id(),medOrderList.get(pos).getMediceneName(),medOrderList.get(pos).getMedicenePotency(),medOrderList.get(pos).getMediceneQty()));
                            }*/

                        } catch (Exception e) {
                            e.printStackTrace();
                        }


                    }
                });
            }

            return view;
        }

    }



}

Answer 1

just Replace your adapter code with below code and read comment which i have mention in this code

 class CustomAdapter extends ArrayAdapter<MedicineBean> {
    private Context context;
    private List<MedicineBean> medicineBeanList;
    ListViewHolder listViewHolder;

    public CustomAdapter(Context context, int resource, ArrayList<MedicineBean> objects) {

        super(context, resource, objects);
        this.context = context;
        this.medicineBeanList = objects;
    }

    @Override
    public int getCount() {
        return medicineBeanList.size();
    }

    @Override
    public MedicineBean getItem(int i) {
        return medicineBeanList.get(i);
    }

    @Override
    public long getItemId(int i) {
        return i;
    }

    @Override
    public View getView(final int i, View view, ViewGroup viewGroup) {


        if(view==null) {
            view = getLayoutInflater().inflate(R.layout.single_item, null);
            listViewHolder = new ListViewHolder();
            listViewHolder.medET = (EditText) view.findViewById(R.id.mediceNameInHomeList);
            listViewHolder.potencyET = (EditText) view.findViewById(R.id.medicePotencyInHomeList);
            listViewHolder.incrOrDecET = (EditText) view.findViewById(R.id.mediceQtyInHomeList);
            listViewHolder.cancelBtn = (ImageButton) findViewById(R.id.homeCnclBtn);
            listViewHolder.medET.setEnabled(false);
            listViewHolder.potencyET.setEnabled(false);
            listViewHolder.incrOrDecET.setEnabled(false);
            view.setTag(listViewHolder);
            //Add this line 
            listViewHolder.cancelBtn.setTag(i);

            listViewHolder.medET.setText(medicineBeanList.get(i).getMediceneName());
            listViewHolder.potencyET.setText(medicineBeanList.get(i).getMedicenePotency());
            listViewHolder.incrOrDecET.setText(medicineBeanList.get(i).getMediceneQty());

            listViewHolder.cancelBtn.setOnClickListener(new View.OnClickListener() {
                @Override
                public void onClick(View v) {
                    try {

                            //add this line
                            int selectedPos = (int) v.getTag();
                            //Replace this 
                              //adapter.remove(medicineBeanList.get(i));
                              //with this
                       adapter.remove(medicineBeanList.get(selectedPos));

                        adapter.notifyDataSetChanged();
                        /*for (int pos = 0; pos < medOrderList.size(); pos++)
                        {

                            listViewHolder.medET.setText(medOrderList.get(pos).getMediceneName());
                            listViewHolder.potencyET.setText(medOrderList.get(pos).getMedicenePotency());
                            listViewHolder.incrOrDecET.setText(medOrderList.get(pos).getMediceneQty());
                            //adapter.add(new MedicineBean(medOrderList.get(pos).getCust_id(),medOrderList.get(pos).getMediceneName(),medOrderList.get(pos).getMedicenePotency(),medOrderList.get(pos).getMediceneQty()));
                        }*/

                    } catch (Exception e) {
                        e.printStackTrace();
                    }


                }
            });
        }

        return view;
    }

}

}

Answer 2

Delete the value from list then refresh the adapter.

  listViewHolder.cancelBtn.setOnClickListener(new View.OnClickListener() {
                @Override
                public void onClick(View v) {
                    try {
                   String item = medicineBeanList.get(i);
                   medicineBeanList.remove(position);
                   adapter.notifyDataSetChanged();}
                   catch (Exception e) {
                        e.printStackTrace();
                    }
                }
            });

Answer 3

I cannot resolve from any thing then i decide to referesh mean when item deleted the list view with referesh mean list view invisible and then visible with set of new adapter. Becuase when i deleted the listview item .the item is delete perfectly from the array only orblem in in views. Thats when i referesh the listview after delete . Like this.

    listView.setVisibility(ListView.VISIBLE);
    adapter = new CustomAdapter(this,0,medOrderList);
    listView.setAdapter(adapter);